Does 12v wiring deteriorate with heat or age ?

MitchM

.
Jan 20, 2005
1,029
Nauticat 321 pilothouse 32 Erie PA
I am chasing a strange problem w/ some 12 v electrical wiring (properly sized to carry a 5 v signal voltage. I've noticed that when a properly sized (OEM) to carry a 5 v signal voltage gets hot, often the signal voltage drops randomly to 2.3v or so. Assuming the electric connections are sound, clean and good , do 12v copper wires deteriorate due to old age, or heat exposure? continuity checks when 'cold' show no problem.
 
Jan 11, 2014
11,880
Sabre 362 113 Fair Haven, NY
It is not the voltage that causes heat, it is the amperage.

Wire that has been exposed to salt water can have salt migrate up the wire and cause corrosion beneath the insulation.

As wire heats up, resistance goes up and voltage drops. Is this a consistent problem or truly random? What devices are on the wire? Is the wire fused?

Have you considered that the device may be the culprit and not the wire? A failing device could cause more amperage to flow than the wire can handle causing it to over heat.

noticed that when a properly sized (OEM) to carry a 5 v signal voltage gets hot,
Assuming the OEM wire is properly size may be a bold assumption, especially if any of the devices on the wire have been changed.
 
Feb 10, 2004
4,000
Hunter 40.5 Warwick, RI
I am rather confused by your statements. You talk of 12v wiring, so I think that is low voltage wires, not 120V or high voltage wiring. but then you speak of 5V signals, so that suggests wires that do not have any significant current flowing. Then you speak of these signal wires getting hot and causing a voltage drop.
If you are getting a voltage drop in a wire, you absolutely cannot 'assume' that the connections or terminations are good. And performing a continuity check to test the integrity of a wire will tell you very little unless the wire has a very serious problem. A continuity check will not show any significant voltage drop because the test current is very low.
Perhaps you can explain more about your issue.
 

PaulK

.
Dec 1, 2009
1,279
Sabre 402 Southport, CT
Copper wiring can work just fine for decades. Put it on a boat and it may not last a week. Humidity, water, salt, corrosion, crud...
 
Mar 6, 2008
1,174
Catalina 1999 C36 MKII #1787 Coyote Point Marina, CA.
You are speaking of "signal wire", if signal is traveling through it and you are using a DC voltmeter, then you are measuring the average ac signal. And, cold or hot, are you referring to ambient temperature causing the change or that when the wire is energized with the signal?