Can someone explain why the ground side is switched on this fixture? New fixture I installed also has the ground switched. Shouldn't the positive (red) side be switched as a best practice?
The wiring for daisy chained light in older boats....there is no positive or negative until hooked up... I have seen different fixtures in line wired alternately because it didn't matter for DC, incandescent bulbs...and it didn't matter where you broke or made the circuit.
Best practice???? No..but it DIDN'T matter in the big scheme of things and I would bet good money nobody got hurt or burned a boat down because of this.
Do it better if rewiring... if replacing just a couple fixtures or switches...man I wouldn't sweat it.
Do the lights only have black wires and no red wire?
The positive lead should be switched. It is preferred to be colored red on a 12v DC circuit. The light may not have a positive or negative side so it has 2 black leads and doesn't care what gets connected to where, unless the leads are polarized and both black then the positive lead will have writing and or white hash marks on it.
Always test and verify. I may use a 4 conductor cable to run two 12v DC circuits. One is red +, black - and the other may be white +, green - with the darker color of the pair negative. Depends what you are doing and what you have available.
I heard they changed black negative to yellow negative to avoid this type of confusion.ABYC has a standard but they are a relatively new player. Anybody on here have access to the ABYC standard for circuit wiring colours?
If I'm not mistaken switching ground in autos is fairly common... at least it used to be.
It is handy where a light is switched from multiple locations.
One power lead and a chassis ground is generally close by.
Anybody on here have access to the ABYC standard for circuit wiring colours?
Greg
Here is what I have from 2012 ABYC Stds - cant imagine this would change.
Some folks are not pleased with the color of LED lights.
We have overhead lights that have two contacts . By installing an auto bulbs with 2 filaments and adding a switch 3 levels of brightness is done .
WE installed a pull switch for the dim element as it is easily located/understood by a guest .