Grounds on VHO bulbs and GFCI's

Dogbert · #1 08/09/2003, 08:35 PM

I have a Solar 1000L2 dimmer for my two Icecap 660 ballast and four 72" VHO bulbs. The solar comes with a roll of aluminum tape which is supposed to be grounded to earth. This supposedly helps with more linear dimming and better start ups. I also have a regular ground probe in my sump. All of this is connected to a GFCI circuit. I am still burning in my bulbs so I haven't connected them to the ground yet but I just came up with a concern.

The GFCI is looking for voltage on ground, If the bulbs send voltage to ground while they are dimmed or starting up then it seems to me that the gfci will trip multiple times a day. Has anyone encountered this type of scenario before. Should I bring a ground wire out of the electrial box before the GFCI and hook up the lights to that.

Thanks ahead for your input.

rpgraff · #2 08/10/2003, 03:52 PM

Tagging along on this one since I am considering purchasing the 1000LWM. I would be interested in your opinion of the product once you've got it up and running.

Dogbert · #3 08/10/2003, 06:14 PM

Will do. I plan on calling Champion Monday AM to talk about this. The instructions have me pretty excited about what this unit can do.

I would love a PC interface to move this unit into the GUI world. The neptune has a PC interface but wont work with the Icecaps.

cruzer · #4 08/10/2003, 06:51 PM

Hello all,

This is not an answer to the question just a tag along question. I put a set of 72" VHO's over my 180 and when the VHO's come on it trips my GFIC's. I do not have them grounded in any manner. What really puzzles me is the lights are not even in line with the GFIC's. They may be on the same curcit in the house but are not plugged in to them directly. Anything I should look at??

Thanks for any info.

Rob,

salty joe · #5 08/10/2003, 10:41 PM

Rob,

If there is a shared common ( white wire) on a circuit, a GFI wiil trip as soon as it is loaded.

HTH
Joe

cruzer · #6 08/10/2003, 11:24 PM

Thank's Joe,

I do not know if the GFIC is being to sensative or if there is a problem with the new ballast. When I turn the ballast on it trips one of my GFIC's every time and one other about half the time. The ballast fires up and works fine though, just turns some of my other stuff off. It will sometimes trip when I turn the ballast of also. Do not mean to take over this thread just thought it was close to the same info. Also I know I do have a lot of stuff running of the same breaker if that would make a difference. I do not ever pop the breaker though.

Rob,

Dogbert · #7 08/11/2003, 06:59 PM

I figured that even though the bulbs weren't broken in yet i'd hook up the Solar and the ground system. I used alligator clips to connect to the foil strip and an 18 ga. solid core wire connected to a plug on the power strip. The power strip is the same one that supplies juice to the Iwaki pump, solar controller and both Icecap ballast. The power strip is an APC Net8 unit. I liked this unit because it has a <40 volt let through on any surge and a 25k warranty against damage. The APC is plugged into the GFCI and is the only thing on this circuit.

I plugged everything in, turned on the power strip and pop went the GFCI. I reset the GFCI, the lights began to light and pop went the GFCI again. I then unplugged the solar from the icecap dimmer port and reset the GFCI, the lights flickered and pop went the GFCI. I then removed the alligators from the ground tape, reset the GFCI and all was well. I turned everything off and plugged the Solar back in, turned back on the juice and all is still well.

My next thought is to wye the ground in the j-box before the GFCI and extend the ground outside of the outlet. I will then connect the light ground to the extended ground and try the test again. The sump ground will remain on the GFCI for safety.

I have played around with the dimming feature on the Solar and found that my actinic blues come on at 20% and the aquasun bulb came on at 35%. From these points up you can see a gradual up/down ramp. The FAQ's I have read indicate that 100 hours of burn in time on the bulbs and the ground system will make the dimming/undimming(Can't think of a better word) process better.

Dogbert · #8 08/11/2003, 07:09 PM

I posted a link to this thread on Icecaps forum so they have some visibility into this. http://archive.reefcentral.com/forum...hreadid=227093

Dogbert · #9 08/12/2003, 01:16 PM

Ok, I just talked to Champion Lighting on this issue. They advise that even with the ground tied to something else and not going through the GFCI the Neutral is still being monitored by the GFCI and it will still trip because some of the voltage is missing between the hot and neutral. I looked up the operation of a GFCI on the web and found that not only is ground being monitored but more importantly the differential of voltage between the hot and neutral sides. If there is a differential then the GFCI will trip because the voltage should match exactly on both sides and there should ideally be no voltage on the ground assuming all is well. This explains to me why when big power sucking devices start up that the gfci's will trip. Some of the voltage is used to recharge the capacitors and other circuitry and wont be returned.

The two options in this situation is to place the Solar, both Icecaps and the bulb ground on a non GFCI protected outlet or go without the ground on the bulbs.

Option 1: This will work but gives a chance the I will be cooked one day if there was some sort of short and the voltage is able to get into the water. The ground probe in the sump should take care of this voltage but there is still a chance that I might become a better path to earth and get barbequed. This chance is remote as the lighting has nothing to do with the water path but the danger is still present.

Option 2: Go without the ground on the bulbs and leave everything on the GFCI's. The only negative to this is that the bulbs wont be as linear when they dim up and down. I'm going with this option.

traveller7 · #10 08/12/2003, 10:38 PM

Interesting. I am running 2 solars and 2 660's without issue. Mine are the older solars, the dimmers and 660's, etc. are on differnt gfci circuits.

I wonder if I am going to have issues when I cut these over to my 3kVA UPS......we shall see.

hlehmann · #11 08/13/2003, 01:02 AM

Most flourescent ballasts have a label stating something similar to "mount no more than 1/2" from a grounded reflector." The reason for this, besides safety, is to help start the lamp when it's first turned on. The gap between the grounded reflector and the inside of the tube forms a slight capacitance, which helps the gasses inside the tube to become ionized when it's first switched on. You may have noticed than when a fixture does not have a grounded reflector it sometimes helps to rub your hand on the outside of the tube to get it started. Your hand is creating the added capacitance in that case, substituting for the lack of a nearby grounded metal plate.

As for GFCI's, they do their job by measuring the instantaneous difference in current (NOT voltage) flowing through the hot (black) wire and the neutral (white) wire. If there's the slightest difference, it means that some of the current is getting back to its source through some other path, such as a human body. It only needs to detect a difference of a few milliamps to trip. Normally, if all the insulation's good, all the current coming through the black wire will also return through the white wire. However, some electronic circuits, including switching power supplies, electronic ballasts, etc., have filter capacitors from hot to ground. Sudden spikes while turning on can cause enough current to flow to ground, rather than back through the while wire, to cause an unnecessary trip of the GFCI.