Mayday, Mayday, Mayday?. Technical Question Regarding Electrical??

Walker_

AC Members
Feb 10, 2005
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Left Coast, Canada
Mayday, Mayday, Mayday…. Technical Question Regarding Electrical……+ Pics

Hey all I seem to be encountering some trouble with my new tank im setting up, and im hoping maybe there are some experts out there that may be able to lend some advice as to just WHY this is happening…. And if possible provide a safe solution…

Ok so im getting my new 90Gal planted tank ready, at the moment it is dry, I have all my plumbing and electrics nicely tucked away in the stand. I have mounted surface mount electrical boxes that are rated for the exterior of the building in the stand. I have all my cables running from box to box in exterior rated conduit, and I have water tight seals on all the conduit-box connections. Main power comes into the stand Via a wall plug. This is then fed into a GFI unit. This particular GFI does not have plugs on the front, it simply has a trip/reset switch and then on the back it has power in and power out. Power is then split from the out of the main GFI to a variety of plugs and switches to run all the assorted pumps, sensors and selonidies. Power is also split to 24hr digital timer to run the lights. The power OUT from the timer then goes into ANNOTHER standard GFI WITH plugs, where my lights are then plugged in.

I have two 400w Metal halide bulbs, each with a separate IceCap electronic ballast. I have mounted the two ballasts in a steel box. Power for this box comes from a power bar that I mounted inside the box, the power INTO the power bar is plugged into the above mentioned GFI. Attached to the power bar are the two ballasts, a 12V transformer to run the fans in the lighting hood, AND a 120V fan that a mounted in the steel box that holds the ballasts.
All the marreted connections in the whole stand were done with Diox Grease and were then hit with heat wrap. I am very confident that the connections are all good, and seeing as the tank has not been filled yet I am confident that there is no water in the system….


THE PROBLEM……..
I can put a constant load anywhere in the system with no problems, HOWEVER If I energize the line going to the ballast box, after 30-120 seconds the closest GFI in the line trips!!! I am at a loss as to why…

-Do ballasts do something funny with their power when they are warming up bulbs?

-Could a transformer be pushing power back up the line?

-Or could the 120V fan be causing trouble?

-Would a GFI trip if too many amps are being pushed though at one time…. Then further to that question how many amps would two 400W ballast need to START?


Anyway my solution will obviously be simply give the lights power that is NOT through a GFI, but considering the amount of over engineering iv put into this thing it seems like a defeat for me to do this…. So any hints as to what the issue may be would be great!!!! If my descriptions have been to cryptic ill post pics and a diagram…

-Walk
 
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I’m thinking I read you only have one GFCI. If you have 2 GFCI running one into the other then that will cause it.

But I have had problems with ballast overloading and tripping GFCI systems.

I would cheek the amp ratting of your GFCI box. I have seen a lot of tem ratted at 10A. You might have to much amps with the Metal halide. With just your lighting your pushing 6+ amps. At startup I think it’s about 12 amps.


With larger tanks I like to run a dedicated circuit of the breaker box (I would use a 20A GFCI with 10 gage wire).
 
Hey man, thanks... yes the lights DO have 2 GFIs in line, however I can put a load, such as a room fan after the second GFI and there are no problems... The GFIs are both rated for 15Amps continuis and 20 Amps peak.....
Ill try just plugging it into one of the GFIs, and see what happens.....


PS anyone know the formula for Watts, volts to Amps? I know the Ohms law one, but I dont think that works for AC power, you need to correct for the phase shift I think....


Here are pics and Diagrams of the whole set up, I know its a bit ratty still but it is a work in progress, IE no canopy hood, no doors yet... but ill post pics of the whole thing when done if anyone wants to see them.....

hopfully no one here is still on Dialup :)
-walk

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The line that trips... how many amps is that line rated for? (including wire gauge, switches, etc.). You may be just pulling too much power and it's tripping the GFI. I know I had that problem with my computer + tank equipment. I plugged everything into a 1500 va power supply that was plugged into one outlet. Although I did not have this set up with a GFI, I was pulling too much power through one outlet and caused me to rethink my strategy...

by the way... NICE plumbing :) You should come down here and work as a subcontractor. All the plumbing I've seen on our jobs is crap!!! :)
 
you are definatly pulling to many amps.volts has little to do with power,amps are what makes everything work.you need to find the amps for all your items and make sure that the curcuit they are going to is rated for the amperage.every thing from wire size to how things are tyed together effects your amp draw.Do you know any electricions?might be time to call in a pro.just my 2c.
 
now that i look closer at this mess,i got to ask how many dedicated circuits are you employing from your breaker box?Forget all the b.s. youve done,if you arent using at least 3 20amp circuits to drive this your asking for a fire!Thats why your gfi keep tripping.you need to call a cert.electrician.please.
 
angrytodd said:
you are definatly pulling to many amps.volts has little to do with power,amps are what makes everything work.you need to find the amps for all your items and make sure that the curcuit they are going to is rated for the amperage.

Well, kinda/sorta. He's running 120vac, so the 400w bulbs alone pull 6.5 amps all by themselves. If he was running 230vac, they would only draw 3.4 amps. I'd suspect that the start-up amperage is too much for the GFI's. They can't take all that inrush current. Can you turn on the bulbs one at a time? ...one after the other is fully warmed up? Otherwise, I've had problems running chained GFI's (not sure why, but overall current is reduced when there are two in-line). ....suggest getting rid of one in favor of a simple junction box.
 
I think you should just split the power for your tank needs to two circuits in your house. Most rooms have two (or more) circuits (if they were built within the last twenty years). I split both of my power strips between two outlets on two circuits in my apartment to avoid any complications later on.
 
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