DC8 trips breaker.

[Derek03]

My DC8 keeps triping my breaker. It is a dedicated 20amp breaker. All I have pluged into the circuit is a korilla 4 and the DC8 which has my 3 MH lamps pluged into it. What I cant figure out it only trips at night after everything has shut down. My K4 is on a standalone timer which turns on every 30 min and runs for 15 min. My lights come on in 15 min intervals and off the same way. The breaker never triped before the addition of the DC8 2 days ago. But now every morning I have to flip the breaker which starts all my lights at the same time. Would this cause the biggest power draw and be more likely to throw the breaker? Not once everything has shut down?

I am going to try unpluging the K4 tonight and see if that is the problem.

[kenargo]

That doesn't sound quite right; are you certain there is nothing else on the 20A circuit? How large are the MHs?

[Derek03]

Yea I am positive there is nothing else on the circuit. The lights are 2 250w and 1 400w. I installed a subpanel for the fish room. One 20amp for lights and one for pumps. The lights come in 15 min increments and go off the same way. Everything works fine but when I get up in the morning the breaker is tripped. I had the same stuff pluged into the circuit before adding the controller. The only thing that has changed is the DC8 and the K4 running 15min on 30min off. Before the K4 ran constant. I am going to try unplugging it tonight and see what happens. Hopefully I can figure it out by process of elimination.

It doesnt make any since to me either

[kenargo]

Odd; it doesn't seem right that during the night, when the draw is less that you would trip a breaker.

Do you have access to a AC watt/AMP meter; to measure the real draw of the various devices? I have one and use it top balance the 2 circuits I use for my tanks and find it a good tool to have (takes the guess work out of investigations).

[Derek03]

I have a multimeter if that will do the same thing. I pretty much just use it for 12v so im not sure what the other options are.

[kenargo]

No, it would be a challenge to use that meter. I have an inductive unit (which clips around the hot wire and measures the draw. I think I got mine years ago from Radio Shack; it is a Micronta V-A meter and is easy to use. I found a few items that do simular below:

http://www.buypowermate.com/product.asp?product=P3-P4400
http://www.newegg.com/Product/Product.aspx?Item=N82E16882715001

Basically the devices measure the current draw so you can quickly tell which device is causing the issue. It's also great to balance circuits, DCx, etc to verify you are not over budget on amperage.

Without one I can't immediately think of an easy way to take the measurment but maybe someone else has an idea.

[clp]

Manually turn on/off all the outlets on the DC8, and confirm that it doesn't blow the breaker. Not likely but this test will make sure there is a not short on one of the outlets of the DC8. If it doesn't trip doing this test, then there isn't really anything in the DC8 that could cause the problem (unless you were 5 or 10 watts from popping the breaker).

Curt

[Derek03]

Well I left everything pluged in and let things run their course and the breaker was fine this morning. It didnt throw so im not sure what was the cause at this point. Oh well hopefully everything is fine and I wont have to worry about it any more.

[prugs]

I suspect a bad 20 amp breaker. They are cheap enough ~$6.

[Derek03]

I am starting to lean towards the breaker as well. It was triped again this morning. I will try and replace it and see if that was the problem.

[dougchambers]

Must be the season. I replaced one of the two dedicated breakers feeding our reef room last night. Everything seems to be back to normal...

[Derek03]

I am still not sure if it is the breaker but something I forgot about was my lunar sim pluged in as well. That is the only thing that goes off after I have gone to bed.

I have manualy turned them off to see if that was the problem.

[Derek03]

Turned off the lunar sim last night and the breaker was fine this morning. I will leave it off a few days and see if the result stays consistant.

If that is the cause would it mean there is something wrong with the simulator? I have noticed it never truely turns off, just very dim when not fed power.

[kenargo]

The LunarSim doesn't draw hardly any current at all; there mist be something else o a combination of things. Bad breaker, close to the current limit of the breaker.

[Derek03]

I believe it is the lunar sim. Since I have turned it off I havent had any problems with the breaker. I know it doesnt draw much power but at the time it turns off it is the only thing using power. Some how when it turns off it is using enough to trip the breaker.

When I found out the breaker was triped it was usually after all my MH were supposed to be on. I would go flip the breaker and it would cause all 3 lights to come on at the same time. I would think that this would cause the biggest strain. The breaker handled that just fine. It is a mystery to me but I think I an going to call neptune and see what they say.