stepping down power for float switches [Archive] - Reef Central Online Community Archives

BeanAnimal

02/02/2004, 03:22 AM

I have drawn up a quick schematic.

The problem with your simple design is that your topoff pump will cycle on and off with the slightest water change. You will need a latching relay circuit to prevent this.

You want the pump to start at the "fill line" and stop at the "full line"

My circuit does just that, along with providing protection for a "dry sump" condition and a "sump overflow" condition. Either could happen in the event of a stuck float or empty top off resevoir.

I have used 12v DC for control and 120v AC for pump power. You could just as easily use 12V with to power 12V power heads. You could also use 12V as the output to control a similar circuit placed in the topoff resevoir. Fail safes on both ends, connected by 2 simple wires and a topoff hose.

See attached file.

I have not tested the circuit or proofread it for mistakes.

Gurus, take a look and let me know if I have erred.

Bill

PLEASE IGNORE THE EXTRA EARTH GROUND THAT IS CONNECTED TO NOTHING! I am to lazy to edit the picture!

ALSO: I must give credit to many other members of this forum for posting latching relay circuits that are similar to this basic design. I by no means have invented anything that has not been used in industry for the last century!

buiryn

02/02/2004, 10:11 AM

Bean,

Nice schematic!

There are a few things you could change to make it better:
Label the normally closed/normally open state for each switch. It's hard to follow how it works without it. It would also help people wire it correctly the first time.
Also, I would replace the two pairs of LED's (DS1&2, and DS3&4) with a red/green bicolor LED. (Radio Shack Cat # 276-012)

Buiryn

BeanAnimal

02/02/2004, 10:31 AM

Thanks for the input. If I get a chance this afternoon I will lable the float switches better and look into using bi-color LEDS.

Any other input would be apriciated. I have a few more pages of similar circuits that I have created for my system.

Bill

BeanAnimal

02/02/2004, 01:00 PM

In addition to the above posts:

Please check back or PM me for updates.

I plan on fixing the shematic a bit and adding a parts list. If there is enough interest I wll design a single sided PCB that you can etch at home...

OR if we get enough people, it may be possible to just have the PCBs made for a small fee.

Thoughts?

headshrink

02/02/2004, 01:20 PM

I don't understand schematics :(

JBarnes

02/02/2004, 05:18 PM

Not sure why you are worried about 110 getting into your tank. If you have a GFCI outlet the breaker will trip before you get voltage into the tank. You're far more exposed to a broken heater putting 110 in your tank.

clutchcargo

02/02/2004, 05:24 PM

I would think using 110V through the switches will cause them to fail quicker. Am I wrong here, wouldn't they burn out from the arc as they switch?
Cjh

greeneyedblackcat

02/02/2004, 05:37 PM

Why dont you just switch the neutral leg of the 110 volts and plug into a gfci outlet ? The hot leg dosent even have to be in the sump.

BeanAnimal

02/02/2004, 06:32 PM

Regarding the last few posts...

Firstly GFCI or not, it's not a good idea to switch 120Vac as proposed. Also, it is not a good practice to switch loads with the neutral only. It is much safer to use a mechanical or solid state relay to switch high voltage loads.

I agree that the heater is as, or more dangerous! GFCI will not keep the heater from hurting your or the fish!

Please dont be lulled into thinking that GFCI is magic. It will only protect you or your house if the FAULT is to ground. In the event that the fault is from Neutral to Hot...you still have a big problem. The circuit does not know the difference between you and a lightbulb, nor does GFCI.

Why do we use it in bathrooms then? Well if your dumb enough to blow dry your hair while in the tub, presumably the tub drain will create the ground path. Ohh wait, don't a lot of homes use PVC waste drains now!

Do the simple safe thing....build a relay circuit that prtoects you your pets, your pumps and your floors.

Bill

greeneyedblackcat

02/02/2004, 07:34 PM

A groundfault circuit interrupter (GFCI) is an electrical device which protects personnel by detecting potentially hazardous ground faults and quickly disconnecting power from the circuit. A potentially dangerous ground fault is any amount of current above the level that may deliver a dangerous shock. Any current over 8 mA is considered potentially dangerous depending on the path the current takes, the amount of time exposed to the shock, and the physical condition of the person receiving the shock.
Therefore, GFCls are required in such places as dwellings, hotels, motels, construction sites, marinas, receptacles near swimming pools and hot tubs, underwater lighting, fountains, and other areas in which a person may experience a ground fault.
A GFCI compares the amount of current in the ungrounded (hot) conductor with the amount of current in the neutral conductor. If the current in the neutral conductor becomes less than the current in the hot conductor, a ground fault condition exists. The amount of current that is missing is returned to the source by some path other than the intended path (fault current). A fault current as low as 4 mA to 6 mA activates the GFCI and interrupts the circuit. Once activated, the fault condition is cleared and the GFCI manually resets before power may be restored to the circuit.

It's not the voltage but the current that kills. People have been killed by 100 volts AC in the home and with as little as 42 volts DC. The real measure of a shock's intensity lies in the amount of current (in milliamperes) forced through the body. Any electrical device used on a house wiring circuit can, under certain conditions, transmit a fatal amount of current.
Currents between 100 and 200 milliamperes (0.1 ampere and 0.2 ampere) are fatal. Anything in the neighborhood of 10 milliamperes (0.01) is capable of producing painful to severe shock.

BeanAnimal

02/02/2004, 08:52 PM

greeneyed,

I am aware of how a GFCI works and the "tripping" or "sensing" current required to create a fault condition. I spent almost 15 years in the coal mining industry, where current and voltage leak monitoring have been taken to an extreme. Many of our systems run between 2 and 5 seperate and simultanious safety monitoring technologies. Including very sophisticated ground fault monitoring.

This however means nothing in regards to the basic point I was trying to make.

It is still VERY POSSIBLE to get shocked without causing a ground fault. Even if the GFCI trips, a person can still recieve a very nasty shock!

LETS be VERY CLEAR. If you are not grounded, then the GFCI will DO NOTHING TO PROTECT YOU...NOTHING NOTHING NOTHING. Your body will complete the circuit and you will be the LOAD. YOU WILL BE SHOCKED OR ELECTROCUTED!

People are falsely led to believe that a GFCI can keep you from getting shocked or killed. It is simply not the truth. The GFCI is a measure of protection that will, in many situations, prevent a dangerous shock. There are just as many situations where it will do nothing to help you.

It is just as ridiculous to beleive that a fuse is in place to prevent shock or equipment damage. A fuse is used 99.9% of the time to prevent catastrophic damge or circuit runaway. Touch the hot lead to a DC devices chasis and the fuse will most likely blow. So will the Output devices and anything else tied to ground without diode or similar protection.

I simply wanted to point this out in my last post without getting technical.

BY all means make it a habbit to install and use GFCI, just don't beleive it will prevent you from getting shocked or killed!

Bill

greeneyedblackcat

02/02/2004, 09:33 PM

Bill, I don’t see any difference between switching a GFCI protected pump through a properly rated waterproof switch to a submerged power head or heater plugged into a GFCI, can we at least agree on that.

BeanAnimal

02/02/2004, 10:30 PM

I agree 100%

As stated, I also feel that GFCI should be used anyplace where water or other substances can cause a ground fault.

My comments were more to warn people not to blindly depend on GFCI to protect them from shock.

This relates to the switching of 120VAC using cheap float switched or similar devices (including poorly made power heads and pumps).

If it is not UL listed, you shouldnt trust it. (Not that UL listing is the end all beat all...but it has proved to be at least a lowest acceptable standard).

I would much rather see "novice" DIYers and electricians use a safer voltage/current around water, expecially corrosive water such as we use in reef aquariums. Relays are ideal for this situation.

Regards,
Bill

greeneyedblackcat

02/02/2004, 11:00 PM

I guess the point to this debate is to limit risks associated with electricity and water, the truth be told one runs the same risk simply plugging in a power head as switching AC current through a properly rated float switch, a float switch and a power head on a GFCI outlet = the same risk as 2 power heads on a GFCI outlet, I agree that ac current should be taken very seriously and wiring anything without electrical expertise is probably not a good idea. In this hobby anyone who plugs anything into a GFCI protected outlet runs the risk of being electrocuted.

Reef Rookie 2

02/02/2004, 11:41 PM

Beananimal, You ought to put these top-off and failsafe controllers together and market them. I feel like I just tried to read chinese looking at that schematic. I'll mail you a check...?

Reef Rookie 2

02/02/2004, 11:43 PM

I'll even sign a waiver releasing you of any and all liability...lol

BeanAnimal

02/02/2004, 11:49 PM

Rookie, give me a few weeks and that may become a reality. I have a lot on my plate right now!

I would love to find enough interest to actually get PCBs made and sell a product. On the other hand, I am more than willing to offer advice to anybody who needs it.

I am not an electronics expert. I just tinker with things and get shocked a lot.

Is there a specific item I can help you with?

Bill

Reef Rookie 2

02/02/2004, 11:54 PM

Can you dumb it down a little for guys like me who don,t work for NASA...? There's always Western Union.?

JBarnes

02/03/2004, 10:35 AM

HeadShrink, I just realized part of the confusion may be that you think the wires of the float switches are exposed. What most folks do is mount the float switch to a PVC pipe and run the wires in the pipe to avoid any water contact with the wires. Use the PVC pipe with a end cap tapped to the thread size of the float switch and you have a sealed environment for your float wires.
http://reefcentral.com/gallery/data/500/17397AutoTopOff.jpg

http://reefcentral.com/gallery/data/500/17397sump_016a

JBarnes

02/03/2004, 10:41 AM

Oops, screwed up the picture. Here you go.
http://reefcentral.com/gallery/data/500/17397sump_016a.jpg

pendulum

02/03/2004, 04:49 PM

just tagging along. Thanks for the info:)

headshrink

02/03/2004, 08:48 PM

I like your idea... haven't seen it done like this yet. Wouldn't be a good idea to add a larger (drilled) cap over the switch to prevent the bobbing water from switching on/off real fast, rapidly?
What did you use to hold it on the acrylic top (what fitting)?

BeanAnimal

02/03/2004, 10:24 PM

Originally posted by headshrink

... Wouldn't be a good idea to add a larger (drilled) cap over the switch to prevent the bobbing water from switching on/off real fast, rapidly?

You missed the point of the circuit I think....

The idea of the latching realy circuit is to prevent just such a thing. It matters not of the floats "bob"

Lets look at the action of a "typical" latch circuit for tank top off.

2 floats are positioned in the sump.

the "START" float is the bottom float. It should be positioned at the water level that you consider the minimum acceptable in your sump. In other words the "REFILL NOW" line.

The "STOP" float is the top float. It Should be positioned at the water level you consider the maximum allowed for your sump. In other words the "STOP REFILLING" line.

When the sump is operating normally, the STOP float is hanging closed because it is not "floating". The START float is suspened open because it is floating. In other words the water level is keeping it from closing.

As water evaporates, the level drops towards the START float. When it reaches it, the float will begin to drop. At some point it will make a connection in the circuit. Once this happens (the connection is made the first time) The top off pump will begin to pump water into your sump. At this point it does not matter what the START float does. It can bob up and down without effect. It is no longer an active part of the circuit. At some point however it will simple have enough water under it to FLOAT again (ready for the next time the water drops that low).

Now the top off pump is running and putting water into your sump. The top float is the thing that is keeping the circuit alive. When that water starts to rise and lap against it, it will also begin to FLOAT. At some point it will break contact with the circuit and STOP the filling process. Once it breaks contact, the process stops and cannot start again until the START float is once again activated. SO again it does not matter if it "bobs" up and down at this point.

NOW all of that siad...using two floats without a latching circuit will result in something similar to the following.

No matter how far apart the floats are, the water will never reach the bottom float, if the water drops slightly below the top float, the circuit will kick on and fill the sump just enough to turn it off. You will keep your sump full. But in tiny itty bitty squirts. The floats will bob, kicking the fill pump on and off over and over again. Anoying to say the least.

I hope this is not confusing...I tried!

Bill

headshrink

02/03/2004, 11:21 PM

I thought the second switch was a backup.... to kill the circuit if the first jams open.....

Ereefic

02/03/2004, 11:50 PM

Headshrink,

In the diagram I have attached, that is exactley what will happen.

The first switch (water level) will drop and turn on pump. When the switch rises, it shuts off the top off pump.

IF that switch fails and sticks on, then when the water level rises and makes the second switch (back up) float, it cuts the power to the top off pump.

Very simple, very effective.

BeanAnimal

02/03/2004, 11:53 PM

In the circuit proposed by H20ENG there are only two float switches. One to start the fill process and one to end it.

The relay is what actually monitors the process. If you wish to know how and why it functions I can explain. Otherwise just suffice to say it works :)

In MY circuit. I have added 2 extra float swithes. The switch on the very top is simply a last resort protection to prevent overflow of the sump if the topoff circuit were to stick "on". It simply works by cutting power to the entire topoff circuit in the event of overflow.

The 4th FLOAT is located at a level in the sump where the return pump begins to suck air and cavetate. This float simply shuts the power off to the return pump. This would happen if the sump did not refill for some reason.

My circuit is a simple upgrade from the style H20ENG published here. My circuit could use more work and some features also. Stay tuned for updates over the next few weeks.

Bill

MarkS

02/04/2004, 01:03 AM

Could you simplify that diagram down a bit? I was going to draw up my own PCB diagram, but realized that you had four float switches. I understand what you're trying to do, but that is overkill. Two should be more than enough. Otherwise you've got more problems than you know and would possibly need to rework your setup.

I also did not or could not tell the ratings for the resistors and diodes.

clutchcargo

02/04/2004, 09:46 AM

Bill,
I studied your schematic (note: I don't read schematics) for a few minutes and that's brilliant. I never thought of using the same relay to switch itself. Comment about S4 though, if it ever comes down to S3 failing open and the level drops to close S4 the resulting circuit would cycle itself on and off as the level of the sump changes from the resulting loss of power to the pump. I think it would be a better idea if you relay a backup topoff pump.
Another option would be to replicate S4 and S1 to work as the backup top off range.

BeanAnimal

02/04/2004, 12:25 PM

Its funny you mention the flaw in my shematic....

I was also looking at it last nite and realised the same thing. As the return pump kicks off, the return line will drain...causing the water to rise just enough to cycle the return pump back on, filling the return line...and so on and so on.

I have redesigned the circuit with a 2 float failsafe latch. The same could also be done for the sump overlfow portion of the circuit. A latch could be used that has to be manually reset with a manual switch or another float added.

I can post the new shematic if anybody is interested.

Some might hav a problem using 5 or 6 floats to control a simple circuit, but in reality they have to be there if you want true "automation" that you can be comfortable walking away from.

As far as brilliant, (I could be..hrmm) but the "latching relay" has been around since relays were invented. Thank H20ENG and others here for their work also. You local water company uses the same basic circuit to manage their tanks and resevoirs.

Regards,
Bill

BeanAnimal

02/04/2004, 12:45 PM

Originally posted by MarkS
Could you simplify that diagram down a bit? I was going to draw up my own PCB diagram, but realized that you had four float switches. I understand what you're trying to do, but that is overkill. Two should be more than enough. Otherwise you've got more problems than you know and would possibly need to rework your setup.

I also did not or could not tell the ratings for the resistors and diodes.

Firstly, if you read the above post, there is a simple design flaw in the "sump dry" protection circuit that can be easily fixed.

Second, If you want a simple 2 float solution please see the thread by H20ENG.

Now... that said if you understood what I was trying to do then you would realize that it is not overkill. If you still think it is overkill then you don't understand what I was trying to do :)

PLEASE read this post (really the bulk of the thread)

READ ME PLEASE! (http://archive.reefcentral.com/forums/showthread.php?postid=2355070#post2355070)

If you read the post in that thread you will realize that the extra floats make the curcuit exponentially more reliable from a safety standpoint. Again their is a higher potential of single compnent failure, but that failure can not cause a disaster. In a 2 float design there is a much greater chance of a sinlge component failure cuasing a disaster.

As for "tweaking" it should be straight forward. Really no different than a 2 float system. We are not talkin about tuning a six pack carburetor with dual, dual points spring advanced distributors here.

Regarding PCBs... I will have a PCB designed within a week or two for my circuit. If there was enough interest, a small production run can be ordered. If not then etching em at home would be pretty easy.

The resistor rating will depend on the input voltage and the current draw and voltage rating of the desired LEDs.

There are a TON java calculators on the net to calculate the value for a current limiting resistor for LEDs. In my case the LEDs are standard 20Ma RED and GREEN LEDS rated at about 2.0v The resistors are in the 600K neighborhood, and at 12v will limit the leds to someplace around 15mA. Be warned that most "wal-wart" power supplies output a few more volts than the label says.

Bill

Ereefic

02/04/2004, 01:17 PM

That sounds like overkill to me too.

A 2 switch system is more than enough. There are many different auto top-off systems available and they use 2 switches. Many people have had them in operation for a long time without incident.

Whatever system you use, without regular maintanence, it can fail.

clutchcargo

02/04/2004, 02:00 PM

I think what people don't realize is that rather than topping off 50x day with a couple oz of water at a time as with 2 float switches wired in series, BeanAnimal's system will top off only a few times a day with a larger volume of water (whatever the volume is between the two primary float switches). These float switches, relays, and pumps have a finite number of cycles before they fail, fewer cycles means they'll last longer.
Bill, you could simplify the schematic by throwing out the overflow failsafe relay and running S2 and S1 in series. As far as I can tell the only real purpose it serves is to operate the failsafe leds. Unless the relay fails in the top-off run position. I've never had one fail that way before.

With that said, I currently use the system described by Ereefic mainly because I don't have a sump.
Besides all that I'm a firm believer in refreshing all the float switches and relays once a year.

barebottoms

02/04/2004, 02:04 PM

IMO, I don't think its overkill. 4 floats is the minimum required for proper failsafe for:

Over Fill
Under Fill
and Proper RO useage.

Without Failsafe, you need to floats for proper RO usage. Min and Max to prevent the RO from filling and stoping for short durations.

1st level of protection is to have overfill protection. So you put in a Float to kill power if your topoff Max float gets stuck. So you're at 3 floats now.

Why limit yourself to overfill protection, the pump can be pretty costly too. So might as well protect that with a min float.

Now were at 4. Thats only about $12 for 2 way protection. You normally would want overflow protection anyway.

BeanAnimal, if you do make a single side pcb layout, I'd like to play with it. Do you think you can make the float swith connections for standard header strips? I'd like to experiment with optical sensors and capacitance sensors.

And maybe some kind of connection for the relays so I can try out SSR's too. But I can't think of any industry standard for the interconnects for that.

Thanks!

BeanAnimal

02/04/2004, 02:37 PM

Originally posted by Ereefic
That sounds like overkill to me too. ....
... A 2 switch system is more than enough. There are many different auto top-off systems available and they use 2 switches.

That is a strawman. It does not matter how many different brands or configurations there are. I am sure there are a variety of diffent 2 float systems for sale. You infer that if they are being made and sold, then they are good! Lets not even explore how absurd this is.

Many people have had them in operation for a long time without incident.

And many people have smoked a lifetime without getting cancer. Many people don't wear seatbelts and live through an accident. Many people cheat on their spouses and never get caught. Many people....

Again, the statement is irrelevant to the circuit, its operation or it's reliability.

Whatever system you use, without regular maintanence, it can fail.
That is quite obvious with any "system" that has moving or wear parts. You however HAVE JUST BLINDLY MADE MY POINT!!!

The difference between the 2 systems is the consequences that would result from poor maintenance or Muprhy's Law.

In simple logic...
When the 2 float system fails, the floor floods or the return pump burns up. There is no question about the outcome. It either overflows the sump, or the sump runs dry due to no top-off water. THESE ARE THE ONLY 2 OUTCOMES POSSIBLE!

When the "overkill" system fails, the floor is dry and your return pump lives to see another day. It would take dual or in most cases triple component failure to flood the floor or ruin the pump. THIS IS NOT LIKELEY EVEN WITH 1/10 The maintenace of a 2 float system!

It's not rocket science, its simple logic and a simple circuit. If you don't like it don't use it. If you understood math, statistics or common logic tables, you would see that the "overkill" system is far from overkill. As a matter of fact, it is the simplest system possible to implement a NO SPILLS top-off system.

LETS BE VERY CLEAR
It is a more mainteneace free and maintenance forgiving system.

The resulting LOGIC is also just as simple.

If you use a 2 float system, then you must be very aware that it cannot be allowed to malfunction in any way! How do you do that without standing over it?????

If you use a system with failsafes, then you can walk away confident that in the event of component failure, you will not return to a mess.

Simple logic. If you really wish to see the truth tables for both system I would be glad to post them.

In summation, you can dislike the design, but you are 100% misguided of you think it is overkill. Use what you pleae but don't bash something you don't understand or are obviously not in need of.

You can still buy screw in type fuse panels. That does not mean that installing a breaker panel with Arc Fault and GFCI is overkill does it? Is putting a backup battery on my basement sump pump overkill? I mean with regular maintenance here and at the electric company, my power or pump should never fail right?

Regards,
Bill

BeanAnimal

02/04/2004, 03:34 PM

Originally posted by barebottoms
BeanAnimal, if you do make a single side pcb layout, I'd like to play with it. Do you think you can make the float swith connections for standard header strips? I'd like to experiment with optical sensors and capacitance sensors.

And maybe some kind of connection for the relays so I can try out SSR's too. But I can't think of any industry standard for the interconnects for that.

Thanks!

Quick notes on the design and some other stuff.

I plan on adding standard headers (Molex IDC or similar) available from Mouser, Allied or similar.

Optical sensor are expensive. I have not seen any for less than $50 each.

Capacitence Sensors pose a problem with stray voltage in the tank and corrosion due to the flow of electrons.

SSRs are a good possibility. I have a pile of CRYDOM style SSRs but they may pose a problem with Motors as they are Zero Crossing SSRs (most are). The motor may behave in an unpredictalbe manner or not start at all with a zero crossing relay.

Keep proding me along and I will get something done with this project. I have a million others going on at the same time...

Bill

clutchcargo

02/04/2004, 03:37 PM

Bill, I agree with you, mostly everything is redundant. If the system fails in the top off run (actuated) position, it still tops off. The weak part is if the primary system fails in the off (un-actuated) position. Yes you'll save the return pump but in the mean time the salinity will increase. It would be nice if the system would continue to top off in the low-level state as well.

Your system is fail safe in that if any component of the top off system fails, it will cover itself. Now to take this a step further, what if an unrelated component fails, lets say a cracked pipe return hose spews water all over the floor. The top off will work perfectly but it will empty the contents of the top-off container.

With this in mind, ideally, there should be a timing device built in that only allows the system to run for a set amount of time. Lets say if it normally takes 15 seconds to run the top off then maybe set it to 45 sec and if does run for 45 seconds then the system will default to disable.

We all have our opinion as to what a perfect automated top-off system should be and mine is to be able to take a 2-week vacation with an unattended tank.

Just Brainstorming.
Cliff

Ereefic

02/04/2004, 03:41 PM

BeanAnimal, don't go gettin your panties in a bunch, gheesh.

I am bashing no one. I'm am meerly stating that I think it is overkill. I'm entilted to my opinion right? That's what I thought.

I made no claim that all top off units sold are great and won't fail because they are sold.

Simply to one is not simple to another. I don't know squat about electrical wiring, and that schematic, whoever it was that posted it, means nothing to me and probably about 75% of the people on this board. (Please don't tell me your going to provide statistics on how many people on this board do or don't know how to read a schematic) :)

I'm sure your system will work just fine, I don't have problem with that. But I think for the average tom, dick or harriet on this board that were to use it and not understand how everything actually works, and then run into a problem, have fun trying to figure out how to fix it.

Personally, I don't care what type of system you use.

barebottoms

02/04/2004, 04:02 PM

Bill,

For optical sensors, I use these:

http://www.newark.com/NewarkWebCommerce/newark/en_US/support/search/searchResults.jsp?action=0&First=0&QText=lle105000&x=0&y=0

$20

As for cap. sensor, I was thinking of this design:

Figure 5:
http://www.qprox.com/downloads/appnotes/an-electrode_design.pdf

BeanAnimal

02/04/2004, 06:15 PM

Ereefic,

Let me try and state this another way then. You are entitled to your opinion but...

...you called something "overkill", and then admited that you know nothing about wiring or schematics (or in particular the schematic in question)

Your postion was that "other" systems and people have no problem with a 2 float system. This may be true! BUT it still has nothing at all in the world to do with my shematic or it's status as OVERKILL or anything else. WIthout understanding how my system or the variety of two float systems work, then every single one of your statements is erroneous. So yes when people shoot their mouth off and obviously have done so to offer 2 cents and a jab, about something they know nothing about....it bothers me to say the least.

In other words you labled a circuit design as overkill without knowing anything about it, or any direct comarpisons to other circuits.

So yes, you have the right to offer an opinion, but in the future you should limit your comments to subjects that you understand or can offer contructive input too.

"Simple" may not be the same for all people. That is obvious. Anybody willing to learn is welcome to ask for more help. This is A DIY forum and we are not here to LIMIT our discussion to SIMPLE things. We are here to help each other and learn.

Regarding your comment...

"I made no claim that all top off units sold are great and won't fail because they are sold."

You MOST DEFINATLY did infer this reasoning by stating that many people and companies use and sell 2 float systems. You MOST DEFINATLY did use this as the reasoning as to why a 4 float system is overkill.

Panties in a twist? Not really. Just amused that people can offer an uninformed opinion. Then retreat to the shelter of not even understanding the arguements they used to define their own positions... or matter of factly, outright denying that they even said it.

Now lets get back to designing a great topoff system. If you would like to learn about wiring, circuits or schematics. There are a number of people here who can help.

I was not being a smartass when I offered to explain the difference in the two systems using logic tables and statistics.

Bill

MarkS

02/04/2004, 07:20 PM

Bill, overkill is relative to your particular needs. I need something to turn on an Aqua Lifter pump to pump water from a reservior into the sump whenever the float switch says so. I really don't even need two floats for this. In my application, more than two switches is overkill. It does not mean that I do not understand your schematic. I do entirely. I just do not need that level of protection.

You are taking this WAY too personal.

Ereefic

02/04/2004, 07:34 PM

You should take your ideas to a thread of it's own then BeanAnimal. This thread was started looking for a simple floatswitch with relay. Which people gave him what he's looking for.

Then you come along with the end all of float switch systems. Great if that's what your looking for, but he was not.

Personally, I think it's OVERKILL. Sorry if you don't like someone thinking that your idea is overboard. That's your problem not mine.

Just because I don't understand a schametic, doesn't mean I don't understand what your system will do and how it works. That is 2 totally different things. And I never said I didn't understand what it will do.

I agree with MarkS, you are taking this way to personal.

BeanAnimal

02/04/2004, 10:24 PM

Lets get this straight...

Ereefic:
...yes it is personal
...no I wont take it to a new thread.

MarkS:
...This thread was not posted in regards to your needs. I am glad you understand my circuit. I also understand that you (or others) may not want or need anything more complicated than a single float, or a bucket for that matter.

Your comment was not taken as personal, your explanation and reasoning are sensable and i respect that. Thank you for taking the time to look at my schematic.

My problems is the Ereefic...and again he made it personal, and I feel compeled to reply!

NOW for what has transpired and where we all stand...

I answered a thread to try and help a fellow DIYer (headshrink)

The orignal poster wanted to know how to keep high voltages out of the sump.

The natural progression was to try and explain a relay circuit to him. Some folks tried.

The first few shematics, AND EREEFICs interpretation were totaly wrong. They simply would not provide the desired results.

I simply offered a solution to the problem and answered some questions regarding the solution. Others also offered workable solutions.

At some point the two of you decided my solution was "overkill" or "complicated".... (one of you has refused to even make sense regarding the issue, the other makes full sense)

Ereefic,
AGAIN.. you have a right to an opinion, but who are you to decide what is overkill or complicated for the rest of us? "It's to complicated or overkill for my system" would have been a perfectly logical and reasonable response. You voiced your opinon as a general statement about my design. YOU DIDN'T expect an answer? Are you that isolated from reality?

I answered with a good explanation, and the only response was total SPIN? Instead of realizing your error, you contined to defend it, even contradiciting yourself! At one point you even admit your total lack of understanding of the subject matter. It should have ended there...BUT OHH NO! You gotta try and SPIN it some more.

This is starting to sound more like a political debate! I still stand with the facts in hand and you are off in left field twisting arguements, using strawmen to make points, and outright accusing me of hijacking a thread? Give me a break! Get a clue and reread the enire thread.

And you tell me not to take it personal?

THE BASIC POINTS STILL REMAIN THE SAME!

1) The design is far from "overkill" for any situation where you don't want water on the floor or a burned up pump. (in reality it needs to be a bit more complex than what was posted)

2) Ereefic, you voiced an opinion based on nothing but feeling and MarKs' post. I offered an explanation that fell on deaf ears. You were/are to busy defending your flawed logic, and at the same time trying to ostracise me.

3) You have not come up with a single valid reason as to why the design is "OVERKILL" you have mereley refered to imaginary dificulty levels, the top-off systems available elsewhere, and a few other irrelevant things.

4) Mark you stated that the design was to complicated and Overkill. It may or may not be depending on the desired results and intended application. Isn't this obvious anyway? You said it would be to hard to adjust? In relevance to what? 2 floats? A bucket? A hose? A PLC?

SO yes it is personal when you make it personal. Toss rocks at a guy and at least expect something in return. Would you rather my response have been "yeah gee guys my design is to complicated? That would be intellectually dishonest at best.

Regards,
Bill

Ereefic

02/05/2004, 12:09 AM

The first few shematics, AND EREEFICs interpretation were totaly wrong. They simply would not provide the desired results.

What interpretations where wrong?

AGAIN.. you have a right to an opinion, but who are you to decide what is overkill or complicated for the rest of us?

I decided it was overkill, FOR ME!!

At one point you even admit your total lack of understanding of the subject matter.

I never said I didn't understand what you were trying to do, what I did say was that I didn't understand the schametic.

1) The design is far from "overkill" for any situation where you don't want water on the floor or a burned up pump. (in reality it needs to be a bit more complex than what was posted)

If you say so.

2) Ereefic, you voiced an opinion based on nothing but feeling and MarKs' post. I offered an explanation that fell on deaf ears. You were/are to busy defending your flawed logic, and at the same time trying to ostracise me.

I based my opinion on the fact that I think your system is overkill.

3) You have not come up with a single valid reason as to why the design is "OVERKILL" you have mereley refered to imaginary dificulty levels, the top-off systems available elsewhere, and a few other irrelevant things.

I don't need 6-8 switchs in my sump to do what 2 can do. Therefor, it is overkill IMUNTOO.

Thanks BeanAnimal, this has been fun. :)

BeanAnimal

02/05/2004, 01:37 AM

You have to be joking right?

Sir,

With all due respect, you live in wonderland. If you read this thread from top to bottom, the only thing that is evident, is that you have no point. You made a comment and it was responded to. You continue to make fruitless comments, and I continue to sensibly respond. It has taken you 5 posts to try and spin this enire thing around, and you have yet to accomplish it. However you may win afterall, becuase I am sure that I have broken some forum rule and will be punished or banned from participating here.

As for your view, mine differs once again!

It has not been fun. I come here to learn and to help others, not to argue with a thick headed spinster that is bent on standing his ground, no matter how silly he looks. Who says ignorance can't be bliss!

MY apologies to the rest of the RC community for this entire waste of bandwidth....

Bill

Ereefic

02/05/2004, 02:11 AM

Yes, you have nailed it, I do live in wonderland!! Alice says hi.:D

Throughout this thread, I have not been trying to make a point.
The thread starter asked for info, I gave it. I had an opinion on your top-off system, you didn't like it. So here we are. Two people who disagree.

I was not holding a gun to your head to argue with me, you did it on your own. IF you hadn't taken it so personal, you would have brushed it off and moved on. Well, that didn't happen.

I hope your top off system works for you and you are happy with it. Mine works fine and I am happy with it.

ms71171

02/05/2004, 03:12 PM

I think I agree with both of your opinions.

On one hand, I have to agree with BeanAnimal that his solution is a fully well thought-out, advanced top-off system design, which would work great for those looking for such a setup. Just like many aquarium setups, many are very advanced and many are not. I try to keep things the latter so that the $$$$ dont get out of hand.

On the otherhand, I agree with Ereefic that it is Overkill for many people who just want a simple top-off system. I think you can have both the safety of a relay and the reliability of a simple dual float setup in a series, without all the engineering.

I have to admit I have learned quite a bit from everyone's diagrams and plan on making my own attempt this weekend at adding relays to my systems.

As far as the fill till the top float cuts off the topoff pump, I disagree. I have had a dual float setup for over two years and the way mine is setup the bottom handles the daily topoffs without a hitch and the top one acts as a failsafe only. At least with my sump level, my pump usually only comes on 1-3 times a day for about 5 seconds.

This must of all been a Democat/Rebublican thing or something. This is why I'm an Independant.

:)

MarkS

02/05/2004, 03:28 PM

Originally posted by ms71171
On one hand, I have to agree with BeanAnimal that his solution is a fully well thought-out, advanced top-off system design, which would work great for those looking for such a setup. Just like many aquarium setups, many are very advanced and many are not. I try to keep things the latter so that the $$$$ dont get out of hand.

On the otherhand, I agree with Ereefic that it is Overkill for many people who just want a simple top-off system. I think you can have both the safety of a relay and the reliability of a simple dual float setup in a series, without all the engineering.

Very well put! :thumbsup: This sums it up without all of the name calling and flames. BOTH of you are correct!

I LIKE BeanAnimal's design. A LOT. It is just more than I need. I am in Ereefic's position. I just need something simple. To that end, I have something simple. No reason for the insults from either end.

BeanAnimal

02/05/2004, 04:30 PM

Laugh...i would imagine it's not to hard to guess which party each of the two combatants favors?

In any case...

My design (when actually finished) will have all the bells and whistles that I can think of. However the independent portions of the circuit can be easily "bypassed" with simple dip switches that either permanently "enable" or "disable" a givin float. Easy to setup and use, with only the functions needed for a particular application. Of course if all you want is a simple foat or 2 series floats, then my circuit will be mostly useless.

Best of both worlds. WHY?

Well If I am going to the trouble of designing it, I might as well make it flexible in case somebody wants to buy one from me, or build one themselves.

Once I get the design worked out I will start a thread and post the plans and possibly what it would cost to put one together for the soldering impaired or scared.

Bill

MarkS

02/05/2004, 05:39 PM

I think it would be a good idea if you posted a diagram of how to mount the four switches. That's what's really tripping me up. I just have no clue on this part.

Also, one thing that's holding me back is that I spent $19 on the switch, but with shipping, it came out to more than $25. I rigged up a simple circuit, but misread the coil info on the relay. I sent 120V AC through a 12V DC coil and fried both the relay and the switch (probably due to the power spike you mentioned in the other thread).

I'm on a limited income and cannot justify spending 4X what I did just on the switches alone and have a simular disaster happen.

BeanAnimal

02/05/2004, 09:25 PM

Ok....lets see if we can help.

I will try and whip up a diagram, if i can find some software. I am not an artist! I am not sure what others here use to make those pretty pictures. I use schematic software and visio every day.

Anybody?

In any case, Mark for a limited income, just buy one more relay for now. Wire it up JUST like the circuit H20ENG designed. This will use 2 float switches.

You should not have to pay more than about $6.00 each on them. The relay is about $8 from mcmaster carr.

The H20ENG thread has the mcmaster car part numbers and wonderful pictures!

If you desire bare minimum overflow portection you would put 2 float switches in series instead of one, for the upper float.

I will work on a diagram for you, but it may take a day or so.

My setup works the same as the others except as you have noted, it is a bit more complex and has a higher learning curve. Lets get you started on the simple circuit first and then you can add to it later.

Bill

buiryn

02/06/2004, 09:44 AM

In my last job as a electronics engineer, we would typically create a full blow "thingy" with all the bells and whistles. Then to hit the lower cost markets we would not populate areas of the board to disable that funtionality and save costs. It's less expensive to build one PCB for two/three/four products instead of each having they're own board. (Unless of course you're producing 1000s of them.)
The design that Bean came up with is the bells and whistles auto-topoff. From that design you can strip out the parts that you don't need/want to spend the $$ on now. By starting with a PCB that is designed for everything, you can add options later if needed.
Bean, to help isolate out the sections which are "optional", you can highlight those areas in the schematic along with what other parts would be needed to bypass it. Also, a full parts list would be helpful as well.

Buiryn

BeanAnimal

02/06/2004, 05:20 PM

Worked on the schematic last nite. The modular sections will be clearly marked. A parts list and assembly instructions will also be a part of my final product.

I want to stress that this isn't going to be done tomorrow! I have a lot of other things that are much more important. I also would like input on design flaws or needed options.

Bill

MarkS

02/09/2004, 01:48 PM

BeanAnimal, what about adding a buzzer for the high and low water levels?

Also, since this is going in a project box, why not use BNC connectors for the float switches? This would give the user the option to use one - four switches.

MarkS

02/10/2004, 12:40 AM

Bump

BeanAnimal

02/10/2004, 01:26 AM

BNC connectors are okay, but not corrosion or water tight. For a box in the stand, this is not a good solution. I am looking into some water resistant connections now. Problem is most places want a forune for that kinda stuff. Put $18 connectos on a $6 float...wow! Maybe I can find some weatherproof bncs

Bean

MarkS

02/10/2004, 01:42 AM

They really don't have to be water proof. They'll be a minimum of 24" from the switch.

Aquatic Ecosystems has water proof boxes... Starting at $45 for a 6" x 6" x 4"! :eek2:

BeanAnimal

02/10/2004, 02:04 AM

Bulgin makes very nice waterproof buccaneer type connectors. They are not cheap ($4 - $9) each for male and panel mount. The new Mini series has BNC inserts available.

I agree they don't need to be waterproof. BUt when I overdo something, I overdo it!

$45 is a lot for a box with a gasket! A ratshack project box with rtv would work just fine! I don't plan on getting into it fo rany reason anyway!

Bean

Bean

headshrink

02/15/2004, 08:20 PM

Does anyone have a design where you start with 120V in and out to PH, but there is a transformer in the box to utilize 12V DC float-switch? Is this easy?

BeanAnimal

02/15/2004, 10:34 PM

See any of the design by H20ENG or myself and many others.

You will need a relay circuit. We are using 12v to switch a 120v supply to the power heads.

Bill

headshrink

02/16/2004, 01:53 AM

I'm sorry.... I realize I wasn't clear at all. I have been following up till now. What I meant (was for you to read my mind j/k) was having a transformer/converter inside the project box, so you wouldn't need to plug in a 12V DC trans into the wall - just one 120V AC.
Then I was thinking.... if those transformers are so big, maybe it would be a stretch.... unless you know something I don't, which is very likely.

adidaswood

02/17/2004, 04:00 PM

BeanAnimal,
I think you are brilliant, and I would prefer redundancy and failsafes and overkill as long as my floor doesnt' get soaked.

I would love to see your redesigned schematic..ASAP
Please
thanks

sandsrfr

02/17/2004, 11:59 PM

http://members.cox.net/sandsrfr/2004/TopOffBrains.jpg

Well heres my Solid State Relay/12V transformer project box.

I grabbed the circuit parts, transformer, project box from Fry's Electronics (big electronics store in the mid west), and had the extension cord and the 120v Female plug from a past Home Depot purchase.

Basically the 120V comes in via the extension cord and goes into a distribution block. There it is feed to the 12V transformer and seperate feed to the 'Solid State Relay Circuit'. The 12V transformer provides 5V that is feed into the first float switch and then in 'series' to my second (redundancy/safety) switch, and them into the circuit (into the optoisolator).

When the circuit closes (ie: float switch sinks), Optoisolator triggers the Triac which internally switches the 120V's on to the pump.

I went allittle extravagant by dremeling in the female pump power connector and putting in a plug for the float switches. But I'm happy how it turned out... There is also some vents on the opposite side so the transformer doesn't sweat to death ;)

I've had this for a few months now and boy what else can I say but, WHAT A RELIEF.... No more worring bout topping off except for the once a week filling up of the resevoir.

Heres the link to the schematics I found online:
http://drew.hickmans.net/switching_110VAC.htm

Here's a quick photoshop'd picture of the internals all labeled up.

P.S. If you had concerns about the pump coming on and off all the time with the slightest bit of evaporation (my system usually comes on maybe once every couple hours, with .75gallons of evap. per day), you could just place the hole circuit on a digital timer (for say 5 minutes once or twice a day).

headshrink

02/18/2004, 01:33 AM

:beer:
Very, very nice! Only thing I might add would be an override switch and maybe an LED for fun. Oh, and also need to get some help from dad to understand all this. You did a pretty good job explaining but it is a big learning curve for me. I haven't even heard of most of those parts. Where those part numbers you gave from Fry's?

barebottoms

02/18/2004, 01:47 AM

Originally posted by headshrink
I was having a transformer/converter inside the project box, so you wouldn't need to plug in a 12V DC trans into the wall - just one 120V AC.

Easily done. Its just physically locating it in there.

Easiest way would be to hardwire or use appropriate plugs inside the project box to power the Relay.

More complicated is to take a bare x-former and build a bridge rectifier on your circuit.

sandsrfr

02/18/2004, 02:55 AM

Where those part numbers you gave from Fry's? [/B]

Nahhh, Fry's sells a specific brand of electronic parts (can't remember the manufacturer)... They have these catalogs (index's) that have a 'cross-reference' list in the back of them. You reference the MOC 3031 and the SC141D and get the appropriate item. Its pretty simple..

The diagram/schematic on that site:
http://drew.hickmans.net/images/solid_state_switch.jpg

Then you connect the positive side coming from the transformer to the '+5vdc signal in' on pin 1 of the MOC3031 and you connect the negative lead from the transformer to one of the lead from your float switch. The other lead of the float switch connects to the 'DC ground' on pin 2 of the MOC 3031.

When the float switch lowers, it bridges/connects the leads together and sends a 5v signal triggering the switch.

Here's a quick physical drawings of the basic wiring of the switch:

P.S. Always be careful when working with 120V. Make sure you secure all the wires so nothing can come loose or short out somewhere.