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Dual Batteries Question

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Old Mar 8, 2021 | 12:06 PM
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Dual Batteries Question

I have a 2020 F250 6.2 with dual batteries. I am assuming that they are in series? Also if I disconnect one battery the other battery should keep the memory in the truck? I am connecting some lights to the battery and while I am under the hood and working with the batteries I want to fully disconnect them (one at a time) and apply dielectric grease to the posts. Thanks!
 
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Old Mar 8, 2021 | 12:21 PM
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The dual batteries are connected in parallel. If you disconnect one the other will still be connected and supplying power to the truck.
Be careful not to allow the positive terminal to come in contact with ground. Even with the ground cable removed from the one battery the other battery is still connected to ground.

BTW, if the batteries were connected in series the output would be 24v instead of 12.
 
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Old Mar 8, 2021 | 12:22 PM
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Thank You !
 
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Old Mar 8, 2021 | 01:00 PM
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Safest way, disconnect negative first on the battery you want to work on...... When complete, connect negative last.... Also, not a bad idea to wrap your positive clamp in electrical tape while you do your work....
 
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Old Mar 8, 2021 | 02:29 PM
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Thanks for the great advice. I will do as you suggest!
 
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Old Mar 8, 2021 | 03:15 PM
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Don't apply dielectric grease where you need to make electrical contact. I have seen way too many use it on cable connections and wonder why there is charge issues.
 
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Old Mar 8, 2021 | 05:07 PM
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Originally Posted by ford390gashog
Don't apply dielectric grease where you need to make electrical contact. I have seen way too many use it on cable connections and wonder why there is charge issues.
It affects the charging capability on the batteries?
 
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Old Mar 8, 2021 | 05:13 PM
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Originally Posted by Frank79
It affects the charging capability on the batteries?
Dielectric is an insulator.
 
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Old Mar 8, 2021 | 05:17 PM
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Originally Posted by Crotchety Ford truck only
Dielectric is an insulator.
gotcha! Makes sense that folks are using it for fittings that connect to each other.
 
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Old Mar 9, 2021 | 01:40 PM
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Originally Posted by Frank79
gotcha! Makes sense that folks are using it for fittings that connect to each other.
Dielectric grease shouldn't be used where you need electrical to flow. It is a insulator and often used for the wrong application. I love when people use it in spark plug boots and wonder why they get a misfire
 
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Old Mar 9, 2021 | 01:48 PM
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I thought using Dielectric grease was a good idea on connections. I used some on my Anderson plugs going from my truck to a DC to DC battery charger and it worked fine.
I may have gotten luckily since I didn't use to too much and the pressure the connections put on each other.
Always learn something on this forum.
 
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Old Mar 9, 2021 | 03:35 PM
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Originally Posted by 67_4_ME
I thought using Dielectric grease was a good idea on connections. I used some on my Anderson plugs going from my truck to a DC to DC battery charger and it worked fine.
I may have gotten luckily since I didn't use to too much and the pressure the connections put on each other.
Always learn something on this forum.
If you look it up it's pretty interesting, it's able to polarize, something like a capacitor. I imagine in plugs and things where it's a tight fit and the thin film in and around the pins serves to keep oxidation and moisture from being a problem. I use it on my Fisher plow connections all the time, and other connections. I don't have problems. If it was conductive I would think there would be shorts all over the place. So I don't think the film is thick enough between connections to make them non conductive, but surrounds to keep stuff out, moisture and water included.
 
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