Electrical woes: negative/ground problem? Help!

[Bigjim]

I replaced my DC and AC panels last year and added a bunch of lights and wiring. Everything seemed to be working fine until the last few weeks.

Here are the symptoms:

I installed new recessed lights last year. Recently, when I turn them on they appeared dimmed.
On the masthead I have a tricolor light. It always worked before. We turned it on on our last overnight sail. It did not work.
I have an anchor light on the masthead. It always worked before. We turned it on on our last overnight sail. It did not work.

However, here's another characteristic. All those systems worked intermittently over the weekend. I turned on the water pump and it worked fine. But when the faucets are closed the pump builds up pressure and you no longer hear it running until you open the tap again. Every now and then the pump cycles I was sitting in the cabin when it happened and the recessed lights which were dim, suddenly became full brightness.

Then, in the middle of the night with both the anchor light and tricolor lights switched on, but not working, they both suddenly turned on.

On the way back home, the tricolor light never worked, but the anchor light did turn on.

I'm assuming we have a ground/negative issue. But how can we test this and locate the problem?

FYI, these systems are all DC.

[George_SD]

You need to start solving this sooner rather than later. Either get an electrician or pull out your multimeter and start tracing wires.

It sounds like you have an intermittent short somewhere or really bad (possibly rusty) connections. Start from the fixtures that are not working and go from there. . in some instances this can lead to serious issues and even fires.

[ThereAndBack]

Start at the batteries and check every connection between the terminals of each battery all the way back to the panels. Since it seems like a lot is failing at once.. It seems likely the problem is between the batteries and the panels (that being the most universal of component pieces).

Put the system under some load and check the voltage between every single connection you can get to. Sometimes a bad connection will manifest as loss under load but not if there is no load. Check the tightness of all connectors. Check for corrosion. Look for anything that warms up.

[Wotname]

Originally Posted by Bigjim

..........
I'm assuming we have a ground/negative issue. But how can we test this and locate the problem?

FYI, these systems are all DC.

59.9% sure you have a -ve bus problem; 41% sure you have a +ve bus / main switching problem; 0.1% it's something else.

Start at the battery and check every connection from the battery terminals through to the respective bus.

By checking, I mean disconnect the terminal, clean the mating surfaces, give the wire termination a pull test and then reconnect ensuring it is tight.

If the problem exists after checking every battery / bus connection, pull out your meter and check for voltage drops between the battery and bus (+ve and -ve).

EDIT: Cross posted with There and Back; we are saying the same thing

[Time2Go]

Originally Posted by Bigjim

I replaced my DC and AC panels last year and added a bunch of lights and wiring. Everything seemed to be working fine until the last few weeks.

Here are the symptoms:

I installed new recessed lights last year. Recently, when I turn them on they appeared dimmed.
On the masthead I have a tricolor light. It always worked before. We turned it on on our last overnight sail. It did not work.
I have an anchor light on the masthead. It always worked before. We turned it on on our last overnight sail. It did not work.

However, here's another characteristic. All those systems worked intermittently over the weekend. I turned on the water pump and it worked fine. But when the faucets are closed the pump builds up pressure and you no longer hear it running until you open the tap again. Every now and then the pump cycles I was sitting in the cabin when it happened and the recessed lights which were dim, suddenly became full brightness.

Then, in the middle of the night with both the anchor light and tricolor lights switched on, but not working, they both suddenly turned on.

On the way back home, the tricolor light never worked, but the anchor light did turn on.

I'm assuming we have a ground/negative issue. But how can we test this and locate the problem?

FYI, these systems are all DC.

Some boats have a terminal strip at the base of the mast to facilitate
Unstepping the mast. Sometimes these might even be in the bilge.
I’d check to see if you have this set up and it’s condition.
Might be severe corrosion on a terminal strip.
Cheers
Neil

[TrentePieds]

Nothing for it but to tidy up and clean up. Start at the battery end, pull the terminal clamps and clean them as well as the terminal posts. Re-assemble making sure that the clamps are good'n'tight.

Now follow EVERY single wire throughout your entire system giving each terminal you find the same treatment you gave the battery terminals.

While tracing wires and cleaning terminals, if you run across a butt-joiner (crimp type) anywhere along a wire, cut it out. It is most rare that there is a fault in the wire itself. It is most common that a crimp type butt joiner will let you down. Replace the butt joiner with spade or eye terminals on the cut ends of the wire and connect them via a newly installed terminal block. Any crimp fitting will always be suspect, but now, at least, you can get the probes of your multimeter on the terminal screws to test the wire itself - and the NEW crimps - for continuity and be assured that what your meter tells you is the truth :-).

It'll pay you to make up a sufficiently long piece of 12Gauge wire with crocodile clips on both ends. With that you can test a wire for continuity even if that wire runs from one end of the boat to the other. And even if that wire is run behind the furniture so you can't get at it.

Where all your wire runs from the mast come into the hull, it is essential IMO to have them terminate on a terminal block. If these wires and the wires that feed them via the terminal block are not each of distinctive colour, now is the time to mark them so you, and others, in the future, will know what precisely they do. No need to get fancy. Just a bit of masking tape with the name of the circuit written on it with a "Sharpie" marking pen will do. But labelled they must be :-)! If the wires are of distinctive colours write up a little table to tell which colour does what. Tuck the note in under the ceiling next to the terminal block so it will always be handy.

Have fun :-)!

TrentePieds

[Boatyarddog]

Originally Posted by Bigjim

I replaced my DC and AC panels last year and added a bunch of lights and wiring. Everything seemed to be working fine until the last few weeks.

Here are the symptoms:

I installed new recessed lights last year. Recently, when I turn them on they appeared dimmed.
On the masthead I have a tricolor light. It always worked before. We turned it on on our last overnight sail. It did not work.
I have an anchor light on the masthead. It always worked before. We turned it on on our last overnight sail. It did not work.

However, here's another characteristic. All those systems worked intermittently over the weekend. I turned on the water pump and it worked fine. But when the faucets are closed the pump builds up pressure and you no longer hear it running until you open the tap again. Every now and then the pump cycles I was sitting in the cabin when it happened and the recessed lights which were dim, suddenly became full brightness.

Then, in the middle of the night with both the anchor light and tricolor lights switched on, but not working, they both suddenly turned on.

On the way back home, the tricolor light never worked, but the anchor light did turn on.

I'm assuming we have a ground/negative issue. But how can we test this and locate the problem?

FYI, these systems are all DC.

Personally I'd rig up a ground wire, 12 gauge to your DC negative at the panel directly to the battery.
If this solves or changes the erratic operation of your components, you've found its a ground to your panel, from the feed side.

If that doesn't change anything.
You then will need to isolate each ground from those components, one at a time, switch on each component, and connect the grounded lead from the battery and check the operation of that component.
Sounds like a corroded ground on a common connection point. Perhaps at the battery, or the Neg. panel buss. Or other Neg. buss.
Check those points where there is multi grounds connected.
Multi ring connectors piled on each other creates corrosion problems to many components connected to the common ground.
SV Cloud Duster

[wiekeith]

Originally Posted by Bigjim

Every now and then the pump cycles I was sitting in the cabin when it happened and the recessed lights which were dim, suddenly became full brightness.

There has to be a clue there, doesn't there? Could simply be the vibration of the pump if there's a suspect negative wire 'cluster' in close proximity.

[Stu Jackson]

Originally Posted by Bigjim

.................

I'm assuming we have a ground/negative issue. ....................

Why? Aren't there two wires to each component?

[lordgeoff]

Originally Posted by Bigjim

I replaced my DC and AC panels last year and added a bunch of lights and wiring. Everything seemed to be working fine until the last few weeks.

Here are the symptoms:

I installed new recessed lights last year. Recently, when I turn them on they appeared dimmed.
On the masthead I have a tricolor light. It always worked before. We turned it on on our last overnight sail. It did not work.
I have an anchor light on the masthead. It always worked before. We turned it on on our last overnight sail. It did not work.

However, here's another characteristic. All those systems worked intermittently over the weekend. I turned on the water pump and it worked fine. But when the faucets are closed the pump builds up pressure and you no longer hear it running until you open the tap again. Every now and then the pump cycles I was sitting in the cabin when it happened and the recessed lights which were dim, suddenly became full brightness.

Then, in the middle of the night with both the anchor light and tricolor lights switched on, but not working, they both suddenly turned on.

On the way back home, the tricolor light never worked, but the anchor light did turn on.

I'm assuming we have a ground/negative issue. But how can we test this and locate the problem?

FYI, these systems are all DC.

I would start at the earth on your engine block. Clean all the contacts. If there is a stud take it out and clean the threads into the block and on the stud.

[Bigjim]

Here's another clue: I have two bilge pumps. When I switch the aft pump to AUTO both light up and start pumping. They do NOT turn off when the bilge is empty.

Does that provide any ideas?

[TrentePieds]

Jim:

Re #11: That sounds rather like a LABELLING error! Obviously the pumps are wired to work in unison and to come on, and stay on, when you place the switch in the "ON" position. If the label is on panel faceplate (not on the switch itself), and the switch has been put in butt over teakettle, what you describe is the effect you would get!

You SHOULD have a switch that has PRECISELY that effect you describe, so so far so good.

You should also have an AUTOMATIC switch in your bilge that starts the pumps (both together is okay, maybe even necessary depending on the construction of your boat) when/if the water in the bilge rises to a certain level. That switch should turn off the pumps automatically when sufficient water has been evacuated so that the water level falls to below the level that triggers the pumping.

The switch you are talking about should be so wired into the system that when it is in the "ON" position the juice BYPASSES the automatic switch and thereby causes the pumps to run continuously until you turn the switch to the "OFF" position. When you place the switch you are talking about in the "OFF" position, the pumps should be governed entirely by the automatic switch.

This problem may not have anything at all to do with your greater problem. If you are not sure how to wire the bypass switch, sign out and we can do you wiring diagram.

TrentePieds

[Bigjim]

Originally Posted by TrentePieds

Jim:

Re #11: That sounds rather like a LABELLING error! Obviously the pumps are wired to work in unison and to come on, and stay on, when you place the switch in the "ON" position. If the label is on panel faceplate (not on the switch itself), and the switch has been put in butt over teakettle, what you describe is the effect you would get!

You SHOULD have a switch that has PRECISELY that effect you describe, so so far so good.

You should also have an AUTOMATIC switch in your bilge that starts the pumps (both together is okay, maybe even necessary depending on the construction of your boat) when/if the water in the bilge rises to a certain level. That switch should turn off the pumps automatically when sufficient water has been evacuated so that the water level falls to below the level that triggers the pumping.

The switch you are talking about should be so wired into the system that when it is in the "ON" position the juice BYPASSES the automatic switch and thereby causes the pumps to run continuously until you turn the switch to the "OFF" position. When you place the switch you are talking about in the "OFF" position, the pumps should be governed entirely by the automatic switch.

This problem may not have anything at all to do with your greater problem. If you are not sure how to wire the bypass switch, sign out and we can do you wiring diagram.

TrentePieds

Absolutely not! Please do not assume facts that have not been provided. I installed both pumps two years ago. They have always worked independently of each other. This only started happening in the last few weeks. Besides, the bow pump works fine. But when the aft pump is switched to AUTO it turns both on and they STAY on even when the bilge is empty. That is not correct. The pumps have always worked on AUTO only when the water is high or when switched to MANUAL.

The important aspect of these pumps is that they are wired directly to the batteries and do NOT connect to the electrical panels at all. The switches are separate switches in stalled on the doors but not connected to the panel itself.

Something has changed in the system, some wiring somewhere is compromised and I just need ideas of where to look first. As far as I know, the two pumps don't share any connections of any kind. Although they may connect to the same ground post.

I will be doing some tracing this weekend with a friend who is professional electrician.

[Bigjim]

Update on the ghost bilge pumps.

A friend with electrical experience came on board and helped me troubleshoot the bilge pump issue. It turned out both pumps were not running a the same time. It was only the indicator lights that lighted. It turns out a ground wire for the indicator lights was not connected to ground. But, both switches were wired together on the ground so the power was bleeding across to the other indicator and lighting up the lights to both whenever either light was activated.

Another issue was the PO used solid wire in the connection. But the wire going to the switches was stranded. The stranded and solid spliced using a wire nut. I removed all the wire and replaced it with tinned stranded wire and attached it to ground.


The bilge pumps are now working as expected.

No info on the other electrical issues. We traced the wires to a common bus bar and the power to all the flakey lights was working fine, but there was some bad corrosion on the bus block that I will address this week. Once this is cleaned up I'll keep an eye out for further electrical problems.

[Bigjim]

Here is the wire and connector I removed.