The Ford Barn

Kpar · 02-28-2022, 02:40 AM

Question for members who are more knowledgeable than me regarding electrical. I do know that the bigger the size of the cable the less voltage drop you will get. If I run a 6 meter cable from the battery what size do I need to keep 6 volt at the end. Is this only relevant on what current is being drawn from that cable ?. Reason I ask this is I'm using fog lights for indicators through a couple of relays what size wire for power to the relays. So far I have destroyed 2 relays ?
Comments much appreciated
Keith

corvette8n · 02-28-2022, 08:18 AM

I ran 12ga. wire to my horn and relay as that is what I had on hand, no issues.

Tinker · 02-28-2022, 10:50 PM

As important as the cable gauge size is the length of the cable matters also. 12ga is fairly large. Some thing wants me to say "that is what she said". I digress....

Juergen · 03-01-2022, 08:08 AM

If you ruined two relays (and they were grounded properly) it would seem they carried too much current. Now too small a wire increases resistance so they should experience less current. Too small a wire decreases the voltage at the load so the fog lights would be dimmer. Now if you had a short in the wiring or lamps, the current would increase drastically and burn out the relays. I'd check the wiring and run the lights at the battery to check the load.

Jack E/NJ · 03-01-2022, 08:12 AM

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>>>So far I have destroyed 2 relays ?>>>

This suggests relay amp-ratings were too small. A 35-watt fog uses ~6 amps at 6v. Initial surge is even more till the filament heats up.

02-28-2022, 02:40 AM	#1
Kpar Senior Member Join Date: Feb 2012 Location: Gladstone QLD Australia Posts: 324	6 Volt question Question for members who are more knowledgeable than me regarding electrical. I do know that the bigger the size of the cable the less voltage drop you will get. If I run a 6 meter cable from the battery what size do I need to keep 6 volt at the end. Is this only relevant on what current is being drawn from that cable ?. Reason I ask this is I'm using fog lights for indicators through a couple of relays what size wire for power to the relays. So far I have destroyed 2 relays ? Comments much appreciated Keith

02-28-2022, 08:18 AM	#2
corvette8n Senior Member Join Date: Jul 2010 Location: 36 miles north of Albany NY Posts: 2,954	Re: 6 Volt question I ran 12ga. wire to my horn and relay as that is what I had on hand, no issues.

02-28-2022, 10:50 PM	#3
Tinker Senior Member Join Date: May 2010 Location: MN Posts: 7,053	Re: 6 Volt question As important as the cable gauge size is the length of the cable matters also. 12ga is fairly large. Some thing wants me to say "that is what she said". I digress....

03-01-2022, 08:08 AM	#4
Juergen Senior Member Join Date: May 2010 Posts: 503	Re: 6 Volt question If you ruined two relays (and they were grounded properly) it would seem they carried too much current. Now too small a wire increases resistance so they should experience less current. Too small a wire decreases the voltage at the load so the fog lights would be dimmer. Now if you had a short in the wiring or lamps, the current would increase drastically and burn out the relays. I'd check the wiring and run the lights at the battery to check the load.

03-01-2022, 08:12 AM	#5
Jack E/NJ Senior Member Join Date: May 2010 Posts: 2,173	Re: 6 Volt question Sponsored Links (Register now to hide all advertisements) >>>So far I have destroyed 2 relays ?>>> This suggests relay amp-ratings were too small. A 35-watt fog uses ~6 amps at 6v. Initial surge is even more till the filament heats up.