DC wire connection problem

[paulga]

Hi, I have a DC connectivity problem. The deck lights and bridge lights have their dedicated switches shown below. Both share one DC circuit breaker. The deck lights work as expected but the bridge lights never turned on.

The second picture shows the interior side of this panel. I scraped off some insulation to expose the wires, and jumped the black line of the sundeck light switch to the red line of the bridge light switch, using a short wire. Now when the sundeck switch is engaged, both sundeck and bridge lights tuned on. When the sundeck switch is off, the jumping does not turn on the bridge lights.

Apparently the bridge light circuit has a bad connection where the battery wire joins the switch wire (black). What connectors can be used to implement this jumping? To me it's acceptable to use the sundeck switch to control lights in both places.

 

[SteveK]

If both reds come off the same breaker then all you have done is bypass the sundeck switch.
The reds should both be positive and the blacks go to the respective load (lights). jump the sundeck switch black and red and if it works replace the switch.

 

[Iggy]

The first thing looking at it is to take all that tape off. Find out if the connection should be redone over. Are the switches still good or should be replaced. Also put some sort of strain relief so the cables are not hanging.

 

[sealandsky]

Rather than putting the load of both circuits through one switch (and risk a fire), I'd just replace the entire switch assembly with something like this: WeatherDeck® Waterproof Switch Panel, Two-Position | West Marine

 

[luna]

I would redo the wiring by running one wire from the breaker to one switch and then on to the other switch. I would then run a new positive switched wire from each switch to their respective loads.
All of these wires would be the ABYC recommended color for lighting circuits which is dark blue.
To me using a black wire which could be an ac ungrounded wire, for a dc positive wire is enough to hank the whole thing and do it correctly.
If the switch itself is the problem you could likely replace it or remove it from the panel and take it apart so you can determine what is the problem. It could just need a good cleaning of the contacts.

 

[BB-marine]

I would redo the wiring by running one wire from the breaker to one switch and then on to the other switch. I would then run a new positive switched wire from each switch to their respective loads.
All of these wires would be the ABYC recommended color for lighting circuits which is dark blue.
To me using a black wire which could be an ac ungrounded wire, for a dc positive wire is enough to hank the whole thing and do it correctly.
If the switch itself is the problem you could likely replace it or remove it from the panel and take it apart so you can determine what is the problem. It could just need a good cleaning of the contacts.

That wire looks like a marine Duplex electrical cable. The coloring for them is either red/blk or red/yellow. It is a good type cable to use when two wire electrical circuits are added because it has a protective sheathing. I agree the color coding is not correct but that can be resolved by marking the wires red ( line) black (load).

Testing the switch is a simple procedure. Remove the circuit fuse, remove the wires from the switch. use a VOA meter set on Ohms. Switch on- closed, switch off- open. If the test does not show these results replace switch. If both lights are powered by the same circuit interrupter, fuse or breaker combining them would be ok as long as the switch max amp capacity is more than the total amp draw from the lights. If the lights use individual circuit interrupters I would not use one switch. If it were my boat I would replace the switch if it is the culprit.
Brian

 

[Iggy]

That wire looks like a marine Duplex electrical cable. The coloring for them is either red/blk or red/yellow. It is a good type cable to use when two wire electrical circuits are added because it has a protective sheathing. I agree the color coding is not correct but that can be resolved by marking the wires red ( line) black (load).

Testing the switch is a simple procedure. Remove the circuit fuse, remove the wires from the switch. use a VOA meter set on Ohms. Switch on- closed, switch off- open. If the test does not show these results replace switch. If both lights are powered by the same circuit interrupter, fuse or breaker combining them would be ok as long as the switch max amp capacity is more than the total amp draw from the lights. If the lights use individual circuit interrupters I would not use one switch. If it were my boat I would replace the switch if it is the culprit.
Brian

Yep, what he said.

Marking the wires for polarity and usage is a great thing to do.

 

[paulga]

If both reds come off the same breaker then all you have done is bypass the sundeck switch.
The reds should both be positive and the blacks go to the respective load (lights). jump the sundeck switch black and red and if it works replace the switch.

No, the sundeck part is good. The bridge lights do not work. The voltage between the bridge switch black and red wires is 0. If the red is connected to positive, it should read 12v. So I thought it's a bad connection rather than the switch.

I'm getting +12v b/t the sundeck red and black when the sundeck switch is off. This means the sundeck red is connected to the positive and black is load.

Jumping sundeck red to bridge red, with both switches off, bridge lights turned on.

Jumping sundeck red to bridge black, bridge lights only turned on when bridge switch is turned on (works normally).

Does this mean in the bridge switch, the red is load, the black is line (this one is broken)?

 

[paulga]

That wire looks like a marine Duplex electrical cable. The coloring for them is either red/blk or red/yellow. It is a good type cable to use when two wire electrical circuits are added because it has a protective sheathing. I agree the color coding is not correct but that can be resolved by marking the wires red ( line) black (load).

Testing the switch is a simple procedure. Remove the circuit fuse, remove the wires from the switch. use a VOA meter set on Ohms. Switch on- closed, switch off- open. If the test does not show these results replace switch. If both lights are powered by the same circuit interrupter, fuse or breaker combining them would be ok as long as the switch max amp capacity is more than the total amp draw from the lights. If the lights use individual circuit interrupters I would not use one switch. If it were my boat I would replace the switch if it is the culprit.
Brian

red ( line) black (load) is the correct color coding for DC circuit, right? I.e. red is connected to batt pos, black going to the light (load)

I think the bridge switch has this coding reversed. One solution is to make a connection b/t the sundeck red wire and bridge black wire. In that way the bridge switch is working as expected. What connectors can be used for this join?

The existing likely quick connectors are covered with thick rubber tapes and goos. Not easy to strip.

 

[luna]

Pacer is a respected Wire Manufacturer in the US.
Here is their take on ABCY's color recommendations.

ABYC Color Code Standards

www.pacergroup.net

In the dc world Black is never suppling power to a load.

Once you take this wiring apart to fix its short comings you could use lengths of blue heat shrink over the red and black wires where they are exposed to "fix the colors." You are going to need to cover over the places where you removed the insulation anyway.

I would not install a jumper mid wire like what you show, thats just asking for trouble.

The hardest part will be trying to save the switches from the goo!

 

[SteveK]

No, the sundeck part is good. The bridge lights do not work. The voltage between the bridge switch black and red wires is 0. If the red is connected to positive, it should read 12v. So I thought it's a bad connection rather than the switch.

I'm getting +12v b/t the sundeck red and black when the sundeck switch is off. This means the sundeck red is connected to the positive and black is load.

Jumping sundeck red to bridge red, with both switches off, bridge lights turned on.

Jumping sundeck red to bridge black, bridge lights only turned on when bridge switch is turned on (works normally).

Does this mean in the bridge switch, the red is load, the black is line (this one is broken)?

I bet if you do a voltage test from bridge red to sundeck black you will get 12v too. You do not seem to understand the black (load) is acting like ground feeding through the light bulb to battery negative.
It has been suggested, you have a bad switch or a bad connection.

 

[paulga]

Pacer is a respected Wire Manufacturer in the US.
Here is their take on ABCY's color recommendations.

ABYC Color Code Standards

www.pacergroup.net

In the dc world Black is never suppling power to a load.

Once you take this wiring apart to fix its short comings you could use lengths of blue heat shrink over the red and black wires where they are exposed to "fix the colors." You are going to need to cover over the places where you removed the insulation anyway.

I would not install a jumper mid wire like what you show, thats just asking for trouble.

The hardest part will be trying to save the switches from the goo!

The problem is the bridge switch has no power. The voltage b/t its two wires is 0. In my understanding, the positive wire from the circuit breaker connects at some point to the wire that goes to switch, eg. Sundeck red. It is that point that requires fixing. The switch's other wire leaves the switch and goes to the lights eg. sundeck black or bridge red. Is this correct?

Alternative way is to send a new wire from the breaker to replace the bridge black wire. Both will easily take many weekends. I'd prefer cutting two wires and add a pair of quick disconnectors.

 

[paulga]

I bet if you do a voltage test from bridge red to sundeck black you will get 12v too. You do not seem to understand the black (load) is acting like ground feeding through the light bulb to battery negative.
It has been suggested, you have a bad switch or a bad connection.

Sundeck red to bridge red: 13.3v
Sundeck red to bridge black: 0
(with both switches off), jump sundeck red to bridge red turns on bridge, to bridge black does not turn on bridge

..turn only the bridge switch on, both readings are 13.3. At this time, jump sundeck red to either bridge red or black turns on bridge

I just did the measurements again the results are the same as earlier.

 

[Delta Riverat]

I suggest you run an extension to a known good ground as a reference for your meter. Then proceed with the voltage testing knowing (for sure) that negative is really negative and poke around with the positive lead of the meter.

 

[paulga]

I suggest you run an extension to a known good ground as a reference for your meter. Then proceed with the voltage testing knowing (for sure) that negative is really negative and poke around with the positive lead of the meter.

Just did it. I led a wire from a neg buss bar in a sub panel that is under the bridge control station.

The voltage b/t sundeck red and this true neg wire is 13v. Voltage b/t sundeck black and the true neg wire is 0. So the sundeck red is confirmed to be positive.

Also did continuity test. Continuity exists b/t sundeck black and the true neg wire, and b/t bridge red and the true neg wire. There is no continuity b/t bridge black and the true neg wire. This proves in the bridge switch, the red goes to the load (and further to the ground) while the black was intended to be the positive. No idea if they intentionally made a symmetric pattern of the color coding for the two switches.

 

[paulga]

I made the changes below. When the quick disconnect connectors are coupled, both the sundeck and bridge light switches work as expected.