Reef Central Online Community

Home Forum Here you can view your subscribed threads, work with private messages and edit your profile and preferences View New Posts View Today's Posts

Find other members Frequently Asked Questions Search Reefkeeping ...an online magazine for marine aquarists Support our sponsors and mention Reef Central

Go Back   Reef Central Online Community Archives > General Interest Forums > Do It Yourself

 
 
Thread Tools Search this Thread Display Modes
  #151  
Old 04/26/2007, 08:28 AM
medic29 medic29 is offline
Premium Member
 
Join Date: Sep 2006
Location: Champaign, IL
Posts: 1,516
Okay, I've had the chance to check. I have 2 K4s with Dumas 3004 props (unchanged); both work fine modded. Checked the current/wattage used....15-watts each. This is the rated wattage so it shouldn't be hurting the motor.
__________________
Rick
  #152  
Old 04/26/2007, 12:06 PM
jacmyoung jacmyoung is offline
Premium Member
 
Join Date: Oct 2002
Location: Sacramento, CA
Posts: 1,357
The K4 motor is rated 12W not 15W. But I don't think it will have much issue.

You can estimate the flow by the wattage, for anything between 1000gph to 2000gph, just multiply the wattage by 100 to get the approximate flow.
  #153  
Old 04/26/2007, 01:53 PM
medic29 medic29 is offline
Premium Member
 
Join Date: Sep 2006
Location: Champaign, IL
Posts: 1,516
How do you come up with that way of estimating. It seems intriging, but I think it would also have to do with the size of the magnet, size of the prop, pitch of the prop and other factors, including rpm's of the shaft.

Just curious, how you came about this figure??
__________________
Rick
  #154  
Old 04/26/2007, 10:41 PM
jacmyoung jacmyoung is offline
Premium Member
 
Join Date: Oct 2002
Location: Sacramento, CA
Posts: 1,357
Just pulled them out of my hat

All AC pump props spin at the same speed regardless the size of driver or prop. The speed has to do with the AC frequency.
  #155  
Old 04/27/2007, 12:09 AM
kroe kroe is offline
Premium Member
 
Join Date: Apr 2004
Location: Wallingford, CT
Posts: 1,185
jacmyoung: I love how you have worked out a polished mod for these pumps, but I don't think that wattage * 100 measure is even close.

These presumably spin at the same RPM as MJ mods (no numbers, but based on same prop performance they must). That would put a dumas 3004 unmodified close to 2000 gph.

medic: good work getting the 3004 on there, I was waiting for someone to try one of these low pitch but large props! They seem perfect for the K4 given the large shroud. What did you use for a magnet, the MJ 1200 mag?
  #156  
Old 04/27/2007, 07:27 AM
medic29 medic29 is offline
Premium Member
 
Join Date: Sep 2006
Location: Champaign, IL
Posts: 1,516
Yep, plus I still had some carbon fiber tubing lying around so I used it and was able to cut it to length where the magnet would come out of the motor when the prop was turning the wrong direction, the pop back in and start turning in the right direction. Works pretty good.
__________________
Rick
  #157  
Old 04/27/2007, 09:46 AM
jacmyoung jacmyoung is offline
Premium Member
 
Join Date: Oct 2002
Location: Sacramento, CA
Posts: 1,357
Interesting I had to trim back my Dumas 3004 quite a bit for it to work with my K4 motor. What was the watt rating on that MJMod with untrimmed D3004?

I do see D3004 is very different than most all other props we use, in that it has a much bigger diameter but very low pitch. Maybe such design is more efficient?
  #158  
Old 04/27/2007, 02:57 PM
gpodio gpodio is offline
Premium Member
 
Join Date: Mar 2004
Location: Philadelphia
Posts: 746
Quote:
Originally posted by kroe
[B]jacmyoung: I love how you have worked out a polished mod for these pumps, but I don't think that wattage * 100 measure is even close.
If my knowledge of AC induction motors (from other hobbies) is valid here then I don't believe they all spin at the same rate. The magnetic field rotates at the source frequency (AKA the synchronous speed) but the rotors always spin at a lower rate. The difference is called the "slip %". The more resistance the propeller gives the slower it will spin... The only thing that is the same between pumps is the synchronous speed which is set by the AC frequency.

So finding the best propeller for the tourque this motor can generate is not as easy as it appears, there's a lot to it. At times a smaller prop with a higher pitch will generate more flow than a larger prop with less pitch... or one with an extra blade...

If I'm not mistaken the larger the slip the less tourque the propeller will have, that will play a big role in determining the best propeller.

+++
Edit: Actually, I believe it is more correct to say that as slip rises from 0%, rotor tourque actually increases but beyond a certain slip % it will start to drop considerably. I think I got it right this time as 0% slip woud mean 0 tourque as the rotor would be under no load.
+++

Again, knowledge from another hobby but I do believe AC motors are all pretty much the same in these aspects.

One question, I have a standard 180g All-Glass tank, is the magnetic mount on the #4 model strong enough to rely on? Where did I read someone had theirs slip down on 1/2" glass??
__________________
Giancarlo Podio

Last edited by gpodio; 04/27/2007 at 03:10 PM.
  #159  
Old 04/27/2007, 06:21 PM
jacmyoung jacmyoung is offline
Premium Member
 
Join Date: Oct 2002
Location: Sacramento, CA
Posts: 1,357
It was me, the pump stayed but was close, and the motor had to be at the under side, if the suction cups wear out (we know they always do), the pump will slide.

BTW, thanks for your insight. I think you are right. When I modded with different props, I noticed when the motor was pushed to the limit, the flow reduced while the watt draw increased, must be slipping badly. But at certain working range the slipping effect has to be minimal, else the DC pumps can't have multiple speed settings. Although I think DC motors work differently than the AC ones.

BTW I needed a few K4 parts had a little chat with Bruce at Hydor, a very nice guy. He said Hydor is coming out with a more powerful K pump, probably the same size as K4 but more flow. They also are working hard on controllers for the K pumps.

BTW, my flow=100Xwatt math was not totally pulled out of a hat. I looked at all the AC stream pumps and their factory specs and came up with this simple rule of thumb, just to offer some clue if you can not or don't want to test the flow. Variables such as mentioned above, and others such as how big the opening and how restrictive are the slits too can influence the flow.

Last edited by jacmyoung; 04/27/2007 at 06:28 PM.
  #160  
Old 04/30/2007, 08:57 AM
gpodio gpodio is offline
Premium Member
 
Join Date: Mar 2004
Location: Philadelphia
Posts: 746
Quote:
Originally posted by jacmyoung
It was me, the pump stayed but was close, and the motor had to be at the under side, if the suction cups wear out (we know they always do), the pump will slide.
So the magnetic mount itself still relies on the suction cups for added support? If it's not 100% solid on the magnetic mount alone I'm getting another Seio, my first one without the 90 degree diverter works very well...

Quote:
BTW, thanks for your insight. I think you are right. When I modded with different props, I noticed when the motor was pushed to the limit, the flow reduced while the watt draw increased, must be slipping badly. But at certain working range the slipping effect has to be minimal, else the DC pumps can't have multiple speed settings. Although I think DC motors work differently than the AC ones.
Yeah DC motors vary greatly in speed and you can easily modify their speed by changing voltage, DC motors can slip till they're black and blue in the face and still have good tourque. This is why DC motors have good starting tourque. You'll always have some slip under load in your pump, it's finding that perfect balance between slip, tourque and prop efficiency. It can be surprising at times what prop gives the best results on a particular motor.

Quote:
BTW I needed a few K4 parts had a little chat with Bruce at Hydor, a very nice guy. He said Hydor is coming out with a more powerful K pump, probably the same size as K4 but more flow. They also are working hard on controllers for the K pumps.
Cool! I have worked with AC motor controllers but the ones I have are not suited for continuous running, they get too hot for that.

Quote:
BTW, my flow=100Xwatt math was not totally pulled out of a hat. I looked at all the AC stream pumps and their factory specs and came up with this simple rule of thumb, just to offer some clue if you can not or don't want to test the flow. Variables such as mentioned above, and others such as how big the opening and how restrictive are the slits too can influence the flow. [/B]
You'll likely find that as soon as you modify a single item such as the prop, it will change current drawn, slip and volume pushed, I am not convinced that formula would remain accurate if any one of these things changed. If you could measure watts AND RPM, perhaps one could guess the flow based on prop specs. It isn't easy to measure volume pushed in a such a large cone, perhaps if you "hang" a cork from a string tied to a rock you could compare the angle the string and cork tilt to when placed in front of the pump at a certain distance. At least you'd know which prop pushes more water, the actual flow rate would still be difficult to guess though.

One of these days I'll find the time to play with these things again, I have many props to play with from the old RC boat racing days..
__________________
Giancarlo Podio
  #161  
Old 04/30/2007, 08:58 AM
gpodio gpodio is offline
Premium Member
 
Join Date: Mar 2004
Location: Philadelphia
Posts: 746
Duplicate post...
__________________
Giancarlo Podio
  #162  
Old 04/30/2007, 09:42 AM
bosscrab bosscrab is offline
Registered Member
 
Join Date: Jan 2007
Location: Charleston,SC
Posts: 59
I cant wait for the parts to star tthe upgrades.
  #163  
Old 04/30/2007, 12:23 PM
jacmyoung jacmyoung is offline
Premium Member
 
Join Date: Oct 2002
Location: Sacramento, CA
Posts: 1,357
Quote:
Originally posted by gpodio
...You'll likely find that as soon as you modify a single item such as the prop, it will change current drawn, slip and volume pushed, I am not convinced that formula would remain accurate if any one of these things changed. If you could measure watts AND RPM, perhaps one could guess the flow based on prop specs. It isn't easy to measure volume pushed in a such a large cone, perhaps if you "hang" a cork from a string tied to a rock you could compare the angle the string and cork tilt to when placed in front of the pump at a certain distance. At least you'd know which prop pushes more water, the actual flow rate would still be difficult to guess though.

One of these days I'll find the time to play with these things again, I have many props to play with from the old RC boat racing days..
The K4 pumps are difficult to test for flow, but the Tunze nanostream pumps can be easily tested. It also seems to agree with your DC pump description, when I modded my Tunze 6055 pump, the flow rates (bag tested) more closely followed my 100X watts rule.
  #164  
Old 04/30/2007, 01:05 PM
gpodio gpodio is offline
Premium Member
 
Join Date: Mar 2004
Location: Philadelphia
Posts: 746
I know nothing about the Tunze nanostream, do they use brushless DC motors where the impeller is directly connected to the core or do they use a magnetic coupling from the DC shaft to the impeller/propeller? If they are using brushless DC motors then they work much in the same way as AC induction motors, the biggest difference is in the controller itself which simulates the AC sinewave by switching DC current between the coils...
__________________
Giancarlo Podio
  #165  
Old 04/30/2007, 05:41 PM
jacmyoung jacmyoung is offline
Premium Member
 
Join Date: Oct 2002
Location: Sacramento, CA
Posts: 1,357
I think it is the latter since they share the same propeller units with their similarly rated AC pumps.

I forgot to mention while I was talking to Bruce at Hydor he also showed me a prototype of their upcoming nano K pump the size of an AAA egg, rated 3.5W and 265gph if I remember correctly.
  #166  
Old 05/03/2007, 08:28 AM
bosscrab bosscrab is offline
Registered Member
 
Join Date: Jan 2007
Location: Charleston,SC
Posts: 59
bump. any more pics?
  #167  
Old 05/03/2007, 11:49 AM
Horace Horace is offline
Why do I live in IL?
 
Join Date: Mar 2005
Location: Bloomington, IL
Posts: 4,219
The K4 motor will not turn an unmodded 3004. I tried it several times and i had to cut the prop down several times to get it to work. You have to cut in the neighborhood of 1/8" off the prop to get it to spin.

If there is anyone out there that has been able to get the 3004 to spin unmodded I would love to hear about it. If you do get the 3004 to spin unmodded, I would bet money you have the prop on backwards....... Medic found this out already
__________________
-Kurt
  #168  
Old 05/03/2007, 11:51 AM
medic29 medic29 is offline
Premium Member
 
Join Date: Sep 2006
Location: Champaign, IL
Posts: 1,516
Hey....don't talk about me that way.....But I do have an un-modded one on the other one and it works. Come on over and check it out.....by the way, you can help me out set up the new system! LOL
__________________
Rick
  #169  
Old 05/03/2007, 01:10 PM
jacmyoung jacmyoung is offline
Premium Member
 
Join Date: Oct 2002
Location: Sacramento, CA
Posts: 1,357
Did you check the other un-modded prop and K4 how much watts they were drawing? I bet more than usual. Could be Hydor sent you a K4 with larger motor in it.

They did say they will release a bigger K pump, same size of K4 but more flow, so it is possible they sent you a prototype of the bigger motor by mistake? Of course I can be way off.
  #170  
Old 05/03/2007, 01:40 PM
Horace Horace is offline
Why do I live in IL?
 
Join Date: Mar 2005
Location: Bloomington, IL
Posts: 4,219
Quote:
Originally posted by medic29
Hey....don't talk about me that way.....But I do have an un-modded one on the other one and it works. Come on over and check it out.....by the way, you can help me out set up the new system! LOL


I have no idea how you got it to work, but I will have to bring over one of my impellers some time and see what the difference is. I havent even had luck getting an MJ900 to turn that prop and that is a bigger motor than the K4.
__________________
-Kurt
  #171  
Old 05/17/2007, 06:24 PM
ramullinax ramullinax is offline
Registered Member
 
Join Date: Apr 2007
Location: Phoenix, AZ
Posts: 369
Where would you get an MJ 1200 magnet if you didn't own a MaxiJet?

Quote:
Originally posted by kroe
It doesn't get any easier since I have MJ 1200s with octura props lying around...

If you were to do it from scratch, it would require a MJ 1200 magnet, a piece of carbon fiber tube (or rigid airline tubing), and an octura 1440 (I bet a dumas 3004 would work too). If you have ever modded a maxi-jet before you could either use your existing MJ impeller or make a new one from these parts in your sleep. The one thing left is getting it to start the right direction every time. I imagine this would just require a stopper like everyone uses for maxi-jet mods.

I am not going to find out though because I have four of these in a 92 corner... I don't need or want a single pump to put out more than 1200 gph. If I did I am sure I would have a final version of this souped up koralia running in my tank in less than 30 minutes. I just messed with this one for fun. It has already been restored to stock and put back where it belongs in my tank .
__________________
Ryan

My mom always told me to stay away from the reefer.
  #172  
Old 05/17/2007, 06:41 PM
chem-e chem-e is offline
Reef Ready
 
Join Date: Dec 2002
Location: San Francisco
Posts: 883
Quote:
Originally posted by ramullinax
Where would you get an MJ 1200 magnet if you didn't own a MaxiJet?
They sell them at MJ Mods if you want just the impellor, but it almost seems more worthwhile to buy a new MJ or finding a used MJ for sale by a local reefer.
__________________
"Beer is proof that God loves us and wants us to be happy."
~ Benjamin Franklin
  #173  
Old 05/17/2007, 07:19 PM
medic29 medic29 is offline
Premium Member
 
Join Date: Sep 2006
Location: Champaign, IL
Posts: 1,516
You can also get them from Premium Aquatics; that is where I've gotten my last few. I forget, but I think they are around $8 a piece.
__________________
Rick
  #174  
Old 05/17/2007, 08:32 PM
dhnguyen dhnguyen is offline
Moved On
 
Join Date: May 2004
Location: Kingston, WA
Posts: 4,753
Quote:
Originally posted by Horace


I have no idea how you got it to work, but I will have to bring over one of my impellers some time and see what the difference is. I havent even had luck getting an MJ900 to turn that prop and that is a bigger motor than the K4.

Not all MJ900 motors and magnets are exactly the same strength I have found. This depends on age of the motors/magnets as well as manufacturing inconsistencies. I have been able to get a MJ900 to spin a 3004 Dumas and another MJ900 wouldn't, go figure. If you trim the Dumas prop down just a hair this will help.


D.
  #175  
Old 05/17/2007, 10:41 PM
ramullinax ramullinax is offline
Registered Member
 
Join Date: Apr 2007
Location: Phoenix, AZ
Posts: 369
Quote:
Originally posted by chem-e
They sell them at MJ Mods if you want just the impellor, but it almost seems more worthwhile to buy a new MJ or finding a used MJ for sale by a local reefer.
Why would I spend $18 on a new maxijet when I could spend $10 on an impeller? What does the extra $8 get me?
__________________
Ryan

My mom always told me to stay away from the reefer.
 

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On

Forum Jump


All times are GMT -5. The time now is 09:26 PM.


Powered by vBulletin® Version 3.8.4
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Use of this web site is subject to the terms and conditions described in the user agreement.
Reef Central™ Reef Central, LLC. Copyright ©1999-2009