Turn Signal Wiring

B

Bill Lee/Virginia

Senior Member
I plan to install turn signals on my original 1931 six volt positive ground Tudor. What size wire should I use? Thanks in advance.
Bill Lee/Virginia Peninsula
 
18 ga is adequate for 16 amps at 12 volts or 8 amps at 6 volts.
a 10 cp (High output) bulb draws 2.5 amps.

LEDs draw a lot less power than incandescent bulbs ane are a LOT brighter, but than you have to be concerned about minimum load to let the flasher operate.
 
I have logolites and it is a really nice setup. I would definitely recommend them. They are fairly well hidden, easy to install and the control box inside is removable for shows.
 
Bill Lee/ Virginia: Do a search, there have been MANY previous posts discussing turn signals, lots of good info and wiring diagrams.
Paul in CT
 
Bill, count me as one of the Logolite users. They are real easy to install, and as the others have said, they are all inclusive. The system doesn't care if your car is a six or
twelve volt system. They are super bright, and if you can plug in a toaster----you can install them.

Jack
 
Bruce Adams said:
18 ga is adequate for 16 amps at 12 volts or 8 amps at 6 volts.
a 10 cp (High output) bulb draws 2.5 amps.

LEDs draw a lot less power than incandescent bulbs ane are a LOT brighter, but than you have to be concerned about minimum load to let the flasher operate.
Click to expand...

NEVER! The amperage capacity of a conductor (wire) is independent of voltage. The general constant current limit on insulated 18ga wire is about 8 amps at any voltage. The ability to dissipate heat from the resistance of the wire itself before becoming dangerously hot is the limiting factor. Internal heating of the wire is amperage squared times the internal resistance (ohms) of the wire. What you WILL get when voltage increases is an increase in the power (watts, approximately amps x volts) the wire can carry. With 18 ga wire at the 8 amp limit you can power a 48 watt device @ 6V, a 96 watt device @ 12V, a 1000 watt device @ 125V.
 
What about the voltage drop across the length of the conductor?? The farther from the source, the lower the voltage. I think 14 gauge will be fine. Have used it on cars and trailers for years with no problems. Stranded with THHN insulation.
 
The Logo-Lite System works on either 6 or 12 Volt, negative or positive ground. Uses a 1 Amp fuse to protect the control box. The new unit has a buzzer that sounds and a light that blinks when turing left or right; you can also activate all 4 blinker lights at once in case of emergency.
As previously stated, the system doesn't use any part of the existing wiring so its not necessary to change your wiring harness to install the Logo-Lite system.

Ron
 
Bob from Northport said:
What about the voltage drop across the length of the conductor?? The farther from the source, the lower the voltage. I think 14 gauge will be fine. Have used it on cars and trailers for years with no problems. Stranded with THHN insulation.
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Voltage drop is an interesting concept. If the load is infinitely small (open circuit) the voltage drop will be zero, you will read the same voltage a million miles away, assuming you have a theoretical meter that presents no load. If the load is infinitely high (short circuit) the voltage drop will equal the source voltage only at the end of the wire, be it one foot or a thousand. Your second sentence is true if the load is neither zero or infinity. The same length wire will experience a larger voltage drop with a larger load, as the voltage across any circuit is divided across the resistance of the wire itself and the load resistance. A 46' trailer wired with #18 and half a dozen incandescent tail lamp bulbs may show a 2V drop at the lamps, indicating larger gauge wire is needed, but that same 46' 18ga wire and half a dozen LED tail lamps may only show a few tenths of a volt loss.

I would never use THHN (Thermoplastic with High Heat Nylon overcoat) in trailers unless it was also rated THWN (Wet locations), as both nylon and the underlying non-crosslinked PVC wire insulation have a slight degree of hygroscopicity through sorptive processes. The best wire for automotive use is the cross-linked stuff like OEM harnesses are made from. It does not melt (eventually charrs and burns instead) and is hydrophobic. I might mention that virtually all the wire sold in auto parts stores is NOT crosslinked, it's junk PVC thermo full of hygroscopic plasticizers. Hey, it looks nice. :p
 
Sir:
What do you mean by 220 or 221? I am not familiar with that size/nomenclature. I am simply trying to install turn signals on my Model A as a safety measure. And do not want to burn it up by using inadequate materials. Thanks for your input.
Bill Lee/Virginia Peninsula
 
Bill Lee/Virginia said:
Sir:
What do you mean by 220 or 221? I am not familiar with that size/nomenclature. I am simply trying to install turn signals on my Model A as a safety measure. And do not want to burn it up by using inadequate materials. Thanks for your input.
Bill Lee/Virginia Peninsula
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It is a line from a movie. The guy lost his job and was a stay at home mom. The wife brought her boss home. He decided to pretend he was remodeling the house. The boss asked him if he was going to wire the house for 220. The husband said 220 or 221 what ever it takes.

If you buy a kit for installing turn signals the kit should come with the right size wire. You do not need a BS degree in electrical engineering to complete this project. The kit will have directions to complete the project. I think you are worrying about something that does not need to be worried about.

I did not mean to upset you. I like wiring cars and probably use heavier wire than is required. I doubt if you will have trouble. Just make sure to use the right fusses.
 
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sturgis 39 said:
It is a line from a movie. The guy lost his job and was a stay at home mom. The wife brought her boss home. He decided to pretend he was remodeling the house. The boss asked him if he was going to wire the house for 220. The husband said 220 or 221 what ever it takes.

If you buy a kit for installing turn signals the kit should come with the right size wire. You do not need a BS degree in electrical engineering to complete this project. The kit will have directions to complete the project. I think you are worrying about something that does not need to be worried about.

I did not mean to upset you. I like wiring cars and probably use heavier wire than is required. I doubt if you will have trouble. Just make sure to use the right fusses.
Click to expand...

The movie was Mr. Mom with Michael Keaton in the lead role.
 
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