DC Distribution Panel Help

[Jason2tpa]

I've got a 3 switch Marpac DC Distrib panel I"m having issues with. See pic below. Top switch has 15 amp breaker, middle 10a, bottom 6a. I run my running lights to one switch, baitwell pump to another. First couple weeks after installing the panel it worked perfectly. Not now.

Using a multimeter, there was no resistance measured between positive and negative terminals for each breaker. I then used jumper wires, connecting each breakers positive directly to battery, negative terminal to ground. No problem, switches light up indicating they are receiving power. But once I reconnect power and ground wires (the same wires I had originally installed) and flip a switch it trips the breaker. Before I crawl back under the console in 95 degree heat I'd like to know exactly what the heck is happening.

I recon that since it's tripping the breaker, it's obviously getting power. Therefore it's gotta be the ground, as in the originally installed ground wire, from breaker terminal to negative battery terminal. This wire must be bad. Your thoughts?

[boscoe99]

I've got a 3 switch Marpac DC Distrib panel I"m having issues with. See pic below. Top switch has 15 amp breaker, middle 10a, bottom 6a. I run my running lights to one switch, baitwell pump to another. First couple weeks after installing the panel it worked perfectly. Not now.

Using a multimeter, there was no resistance measured between positive and negative terminals for each breaker. Breakers are not normally used in the negative side of the system. I then used jumper wires, connecting each breakers positive directly to battery, negative terminal to ground. No problem, switches light up indicating they are receiving power. But once I reconnect power and ground wires (the same wires I had originally installed) and flip a switch it trips the breaker. Before I crawl back under the console in 95 degree heat I'd like to know exactly what the heck is happening.

I recon that since it's tripping the breaker, it's obviously getting power. Therefore it's gotta be the ground, as in the originally installed ground wire, from breaker terminal to negative battery terminal. This wire must be bad. Your thoughts?

Do you have a link to a wiring diagram for the panel?

[Jason2tpa]

Do you have a link to a wiring diagram for the panel?

Wish I had a pic, no. And the manufacturer website only has pic of front panel. It came pre assembled with its own positive and negative jumpers. So if you can imagine, the breaker side has 3 pigtailed wire connectors attaching to one of the two terminals. Same setup on negative side. All you do is connect power wire to the positive pigtail, ground wire to negative pigtail. So one power wire and one ground essentially powers all 3 switches. Then you connect the power wire from each accessory into the second positve breaker terminal. Ive got the power wire from ruuning lights going into one breaker, baitwell power into another.

[TownsendsFJR1300]

Correct me if I'm wrong, but all three breakers should have 12 volts to them (from the battery).

Then, you would hook up each circuit, (ie lights, bilge, etc) to each breaker output. This is so they can "pop" if there's an issue with that circuit / pump / etc (saving the rest of the wires, eliminating any chance for fire)

Ground is common, no breaker, no in-line fuses, nothing.

Is this NOT what you have??

[Jason2tpa]

You are correct, all 3 switches have 12v to them via the pigtail. I found a pic online that closest resembles the back of my panel. Notice the pigtailed positive and ground wire, which is what I'm referring to above. Only difference in mine is the positive side of panel has an additional terminal on each block.

Dumb question, when you say "to each breaker output", which side are you referring to? As I mentioned in my initial post, this panel worked perfectly so I know I hadn't reversed the positive wire circuits. But it doesn't hurt to ask.

What would happen if the switch isn't grounded? It would trip the breaker, right? So my thinking is that the ground wire from panel to battery ground is bad. And that is one thing I forgot to check.

[TownsendsFJR1300]

Looking at your first picture, half those wires are to illuminate the bulbs next to the breakers.

The extra positive sounds like the output or line to the lights, bilge pump etc.

The only reason you should need a ground on that switch board in for the built in lights(in the switch-IF I'm understanding that second pic you posted.).

Now you can have all your grounds going to that wire(which MUST be grounded to the battery eventually) BUT, most importantly, each breaker, (when turned on) should have 12 volts coming out if it. That terminal should again go the bilge pump, bait pump, each breaker to each system separately.

Then, that particular system is grounded.


Perhaps if you either have a link with the back pic of that unit would help OR pull yours and snap a picture of it. Shouldn't take long at all to pull out..

[Jason2tpa]

Now you can have all your grounds going to that wire(which MUST be grounded to the battery eventually) BUT, most importantly, each breaker, (when turned on) should have 12 volts coming out if it. That terminal should again go the bilge pump, bait pump, each breaker to each system separately.
.

Just so i'm following you with the above I'll list exactly what's going where:
**Baitwell pump ground wire straight to ground battery, power wire connecting into positive side terminal of panel.
**Nav lights same as above.
Then i have a wire connecting 12v from battery to panel pigtail. The last connection is the ground wire between the pigtail panel ground to battery ground (which I think is the where the problem lies).

That's it, not a sophisticated setup. That's why I"m thinking it's the ground wire from panel to battery ground. Solely because when I hooked up my own alligator clip jumpers, checking each switch individually, the switch lit up.

[TownsendsFJR1300]

Well, if it worked before, it should be hooked up right and I think we're on the same page there..(I hate electric's BTW)..

I don't think the ground is the issue. You may try hooking up one circuit at a time and see if that causes your issue and pops a breaker.

Potentially the bilge pump or bait well pump could be froze up and will pop the fuse once powered up. You did run it for awhile.

If you find one circuit being an issue, isolate it and hook that up (with an in-line fuse) direct to battery and see if it operates or fails..

[Jason2tpa]

I don't think the ground is the issue. You did run it for awhile. ..

You think if the ground is bad it would not trip?? Didn't run lights/baitwell anymore than usual.

Appreciate your input bud. Hope to figure it out this week.

[TownsendsFJR1300]

You think if the ground is bad it would not trip?? Didn't run lights/baitwell anymore than usual.

Appreciate your input bud. Hope to figure it out this week.

Thinking about it, if the ground was bad and the wires got very hot, yes it could pop it.

Also, make sure your breaker is large enough for the electrical part. Obviously, if the say the pump draws more than the breaker, that'll pop it too..

[Jason2tpa]

Thinking about it, if the ground was bad and the wires got very hot, yes it could pop it.

Also, make sure your breaker is large enough for the electrical part. Obviously, if the say the pump draws more than the breaker, that'll pop it too..

That's a great point. I'd have to verify the amerage draw on the pump. but i doubt that it or the bow/stern lights draw more than 12, 10, or 6 amps.

[TownsendsFJR1300]

That's a great point. I'd have to verify the amerage draw on the pump. but i doubt that it or the bow/stern lights draw more than 12, 10, or 6 amps.

No they shouldn't BUT, if one jambed up, got crap in it, etc, that'd pop a fuse as that's what the fuse is designed to do...

Check the grounds, if it still acts up, disconnect, then re-connect one at a time until you find the faulty circuit..

[Jason2tpa]

DC Distribution Panel- Update

Finally got a chance to snap a few pics of the panels backside along with testing each of the circuits. The first pic you'll see a red wire which supplies 12v power and the yellow wire which supplies ground directly to battery. The 3 red and yellow jumper wires distribute power and ground to each circuit. While testing using multimeter the following was discovered:
**12v delivered into and out of each of the 3 breakers
**All 3 switches tested NO resistance between the grounded switch terminal (yellow connection) and accessory terminals.
**While supplying 12v with circuits open, NO voltage detected for each of the 3 accessory terminals.

The last pic shows the frontside of the panel. Those 3 vertical bubble looking domes house a popup button. All 3 of these popup buttons remain in the down position (not tripped) while circuits are open.

These switches/breakers do not house a fuse. So unless I'm doing something wrong here I recon the panel is burnt. But the panel is fairly new, maybe 3 months old. It worked perfectly for 2 months, then crapped out. One test I just thought of would be to remove each of the yellow jumpers and insert onto the adjacent terminal. Then test for power on the empty terminal. Do you think the results would be different?

Your thoughts?

[TownsendsFJR1300]

Jason, IMO, I'd be calling or better yet e-mailing the manufacturer for a picture of the schematic.

With a phone call you can explain the issue(s) and get THEIR feed back.

The wiring diagram should have been included or at least a link to access them..

Its pretty silly for them to sell that without some basic directions....

[rodbolt17]

the pics wont load on my machine.
it is doubtfull the panal failed.
DC electric is simple.

it is water in a pipe.
actually smoke and PFM.

all that breaker is is a bimettalic strip.
if to much current is required(heat) the strip bends and the breaker trips.
a loose ground wire probably would not allow enough current(heat) acrossed the breaker to trip it.
no schematic needed for that panal simply observe it.
typically breakers are labeled line(power in) and load power to the device.