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Best underhood connection

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Hello,
I'm hooking up an ignition switched continuous duty solenoid in my '92 F250 LB, Reg. Cab, a/t, 4X4. This is to charge the aux battery in my slide-in camper while not discharging the truck battery.

Where is the "easiest", under hood, tie-in to the ignition? (The "easiest" that will do the job safely and effectively.) What is the color code for that tie-in if it's a wire splice?

Thank you.
 
Just hook into the +ve wire on the ignition coil - i know it's a little further than the alternator dash light wire but you'll find it easier.
 
The + terminal with engine sunning will only be 7-9 Volts because of the resister in the wirings

IMO you need a battery isolator wired into the charging circuit
 

DNFXDLI

The Token Canadian
Staff member
No need for an isolator to switch a solenoid for aux. battery charging.
 
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"The + terminal with engine sunning will only be 7-9 Volts because of the resister in the wirings"

Would a solenoid connected directly to alternator output yield significantly higher charge to aux battery than the solenoid connected to pos terminal of truck battery?

I want the truck batt to be first in line for charging, wouldn't an alternator hook-up interfere?
 
Last edited:

DNFXDLI

The Token Canadian
Staff member
"The + terminal with engine sunning will only be 7-9 Volts because of the resister in the wirings"

Would a solenoid connected directly to alternator output yield significantly higher charge to aux battery than the solenoid connected to pos terminal of truck battery?

I want the truck batt to be first in line for charging, wouldn't an alternator hook-up interfere?

No higher charge, the voltage will be the same as will the current. You really can't have the main truck battery first in line with the solenoid energized. The only way you could achieve that would be by using a manual switch.
 
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So I'm not giving away any major voltage or current by hooking to the batt rather than the alt?
I'm OK with charging both as long as the aux doesn't drain the main - as I understand it, the solenoid switch prevents that.
 

DNFXDLI

The Token Canadian
Staff member
So I'm not giving away any major voltage or current by hooking to the batt rather than the alt?
I'm OK with charging both as long as the aux doesn't drain the main - as I understand it, the solenoid switch prevents that.

No, you are not giving anything away.
The solenoid won't prevent that as long as it is energized...as in when your vehicle is running or when you have it switched on (manual switch)
If you were drawing more power than your alternator or main battery combination can supply, then it will draw from the aux. battery....however, that is an unlikely scenario.
 
31
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Thank you.
I think I have all the parts ....
I'll plan to do the install before the end of the month - weather permitting.
 
31
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Met my deadline. All done....and....it works.

Yay FTF!
 

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