Trucks 12 volt power lead to trailer battery
How many amps can I expect to recover during a 8 hour drive. Say I use 30 amps per night boondocking and then hit the road again. I have a 150 amp alt. I have 2 twelve volt deep cycle batteries. The o...
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There is a slightly (?) complex upgrade which can charge Trailer batteries AND run the Fridge on 12VDC at the same time. Under "high-load" testing (Trailer parked with Fridge and all lights "ON" plus extra load through an Inverter), a couple of users have been generating about 300W from the TV - and the Trailer 12V system is running at an "effective" battery charge voltage.
If your Trailer already has a Solar system, with an MPPT controller, then the upgrade is pretty cheap. It works by doubling-up the Voltage on the "Battery Charge" wire from the TV, and feeding that into the Solar Charge Controller as a high powered Solar Panel (25-28V, up to 15A). Parts:
* MPPT Solar Charge Controller (expensive - $170 if you don't already have one)
* A "Voltage Doubler" DC-DC Boost Converter, about $30.
* 6 Relays - 5 of them are "cheap" 12V automotive, available anywhere. The lasst one is also cheap, but hard to find: A relay with a 24VDC coil. (That one allows the Trailer to "see" that the Bargeman wire is running at high Voltage: It orders the other two Relays in the Trailer to disconnect the Bargeman from the 12VDC "power distribution panel", and connect it to the MPPT Solar Controller input instead. (The other standard Relay, switched at the same moment, disconnects the "Genuine" Solar panels in favor of the "Fake" Solar Panel connection.) Three "standard" Relays are present in the Tow Vehicle, allowing it to be switched from "12V Trailer Charge Mode" to "24V Trailer Charge Mode".
* A switch for the TV dashboard - controlling "Trailer Charge Mode". You need the switch in order to tow other Trailers. (The Trailer switches automatically.)
* A new Fuse/Circuit Breaker for the TV, and (good idea) another for the input lead to the 24V "Trailer Charge Wire" within the Trailer. It's no longer provided by the 12VDC power distribution center.
* A bunch of wire: Mostly #10, plus a little bit of #8 under the hood (Where the Boost Converter pulls _double_ amps at 13-14.5V, to create "half" the Amps at 26-29V).
Is anyone interested in the details and wiring diagrams?
BTW, JCK: Tow Vehicles typically use "chassis wiring" rules for wiring to the "Trailer Charge Bargeman terminal, they are often undersized (by MY standards). For example: My 4Runner is fused at 30A, and you'd expect to see #10: but the actual wiring was #14.
If your Trailer already has a Solar system, with an MPPT controller, then the upgrade is pretty cheap. It works by doubling-up the Voltage on the "Battery Charge" wire from the TV, and feeding that into the Solar Charge Controller as a high powered Solar Panel (25-28V, up to 15A). Parts:
* MPPT Solar Charge Controller (expensive - $170 if you don't already have one)
* A "Voltage Doubler" DC-DC Boost Converter, about $30.
* 6 Relays - 5 of them are "cheap" 12V automotive, available anywhere. The lasst one is also cheap, but hard to find: A relay with a 24VDC coil. (That one allows the Trailer to "see" that the Bargeman wire is running at high Voltage: It orders the other two Relays in the Trailer to disconnect the Bargeman from the 12VDC "power distribution panel", and connect it to the MPPT Solar Controller input instead. (The other standard Relay, switched at the same moment, disconnects the "Genuine" Solar panels in favor of the "Fake" Solar Panel connection.) Three "standard" Relays are present in the Tow Vehicle, allowing it to be switched from "12V Trailer Charge Mode" to "24V Trailer Charge Mode".
* A switch for the TV dashboard - controlling "Trailer Charge Mode". You need the switch in order to tow other Trailers. (The Trailer switches automatically.)
* A new Fuse/Circuit Breaker for the TV, and (good idea) another for the input lead to the 24V "Trailer Charge Wire" within the Trailer. It's no longer provided by the 12VDC power distribution center.
* A bunch of wire: Mostly #10, plus a little bit of #8 under the hood (Where the Boost Converter pulls _double_ amps at 13-14.5V, to create "half" the Amps at 26-29V).
Is anyone interested in the details and wiring diagrams?
BTW, JCK: Tow Vehicles typically use "chassis wiring" rules for wiring to the "Trailer Charge Bargeman terminal, they are often undersized (by MY standards). For example: My 4Runner is fused at 30A, and you'd expect to see #10: but the actual wiring was #14.
