Truck to camper wiring questions
I am new to the forum and owning a 2003 Lance 815. Vehicle is 1992 F-250 7.3 IDI. Also inexperienced with electrical systems. My plan for the setup is almost always dry camping. So I am really w...
Forum Discussion
Recharging from the truck is convenient when you are traveling between sites. The size of the wire needed depends on
The amphere rating of the connector at the TC also depends on the size of the battery bank as well. Anderson Power Products Powerpole and PowerMod HP lines make quality connectors. Others have used Liftgate connectors from autopart stores.
If you are going to be boondocking a lot, strongly condsider getting quality AGM batteries (Lifeline or Trojan. For all the pluses vs. regular flooded or cheap AGM batteries read the Lifeline Technical manual PDF.
While the resistance / impedence of flooded batteries usually limits charging to 0.1 x 20hr Ah capacity, quality AGM batteries can take up to 5 x 20hr Ah capacity during bulk charging. Faster overall charging. My alternator easily pushed 80A into two 6VDC Lifeline GPL-4ct batteries (220 Ah @ 20hr) through my 2AWG wiring. The converter in my TC typically charges at 0.35 x 20hr Ah Capacity. Think about the future when sizing your wiring. My battery bank is now 440 Ah to deal with boondocking during the winter.
If you are just running devices inside your TC while driving, then voltage drop due to wire resistance isn't as much an issue. If you want to have charging of the batteries while driving, minimizing voltage drop is very important. Lots of online wire size calculators.
Once you've connected your truck batteries (via alternator connection) to your TC batteries. You need to have a disconnect between the two so that you don't discharge your truck battery, while discharging your TC batteries, and stranding you.
Manual switches from online / local marine stores work well, but if you forget it is connected, you can end up with a dead truck battery.
Continuous duty solenoids, "ON" only when the ignition is on, work well most of the time. Although some on this forum have reported being stranded due to arcing of the contacts during connection, causing them to to weld together, fail closed and discharge the truck battery even with the ignition off.
Solid state electronics give the advantage of being automatic, yet avoiding the arcing issue. Traditional, inexpensive silicon diode based "isolators" isolated the batteries, however they had the downside of a 0.6 VDC voltage drop across the device, so not good for efficient charging. Devices from Power-gate from Perfect Switch and Blue Sea Systems have ultra low voltage drop MOSFET isolater, as well as voltage dependent relays that solve most charging / isolating issues (determines which batteries the ECU senses the voltage from to control the alternator output).
Remember to have fuses / circuit breakers near the batteries in both system to protect against shorts and enclose the wiring in split loom sleeving. Blue Sea Systems has fuse holders that connect directly to the battery. Mega fuses and other larger capacity fuses / breakers can be found online at VTE Warehouse
If the 12VDC power in your 7 pin connector is always on vs. ignition controlled, then you might consider pulling the fuse for this line, as parasitic draws of your TC you can still drain your truck battery, even though you have your TC batteries off during storage on the truck.
Finally, while you are rewiring the 12VDC supply inside your TC, if you don't have one already condsider adding a shunt and battery monitor (Trimetric, Xantrex, and others )to get the most lifetime out of your expensive batteries. A good monitor will also let you know when you will need to recharge your batteries to avoid waking up in the middle of the night with the heater just blowing cold air or the LP gas detector sounding due to low voltage.
- Distance to and from the alternator and the TC
- Distance to and from the connector to the batteries inside the TC
- The type of Battery
- The size of your battery bank
The amphere rating of the connector at the TC also depends on the size of the battery bank as well. Anderson Power Products Powerpole and PowerMod HP lines make quality connectors. Others have used Liftgate connectors from autopart stores.
If you are going to be boondocking a lot, strongly condsider getting quality AGM batteries (Lifeline or Trojan. For all the pluses vs. regular flooded or cheap AGM batteries read the Lifeline Technical manual PDF.
While the resistance / impedence of flooded batteries usually limits charging to 0.1 x 20hr Ah capacity, quality AGM batteries can take up to 5 x 20hr Ah capacity during bulk charging. Faster overall charging. My alternator easily pushed 80A into two 6VDC Lifeline GPL-4ct batteries (220 Ah @ 20hr) through my 2AWG wiring. The converter in my TC typically charges at 0.35 x 20hr Ah Capacity. Think about the future when sizing your wiring. My battery bank is now 440 Ah to deal with boondocking during the winter.
If you are just running devices inside your TC while driving, then voltage drop due to wire resistance isn't as much an issue. If you want to have charging of the batteries while driving, minimizing voltage drop is very important. Lots of online wire size calculators.
Once you've connected your truck batteries (via alternator connection) to your TC batteries. You need to have a disconnect between the two so that you don't discharge your truck battery, while discharging your TC batteries, and stranding you.
Manual switches from online / local marine stores work well, but if you forget it is connected, you can end up with a dead truck battery.
Continuous duty solenoids, "ON" only when the ignition is on, work well most of the time. Although some on this forum have reported being stranded due to arcing of the contacts during connection, causing them to to weld together, fail closed and discharge the truck battery even with the ignition off.
Solid state electronics give the advantage of being automatic, yet avoiding the arcing issue. Traditional, inexpensive silicon diode based "isolators" isolated the batteries, however they had the downside of a 0.6 VDC voltage drop across the device, so not good for efficient charging. Devices from Power-gate from Perfect Switch and Blue Sea Systems have ultra low voltage drop MOSFET isolater, as well as voltage dependent relays that solve most charging / isolating issues (determines which batteries the ECU senses the voltage from to control the alternator output).
Remember to have fuses / circuit breakers near the batteries in both system to protect against shorts and enclose the wiring in split loom sleeving. Blue Sea Systems has fuse holders that connect directly to the battery. Mega fuses and other larger capacity fuses / breakers can be found online at VTE Warehouse
If the 12VDC power in your 7 pin connector is always on vs. ignition controlled, then you might consider pulling the fuse for this line, as parasitic draws of your TC you can still drain your truck battery, even though you have your TC batteries off during storage on the truck.
Finally, while you are rewiring the 12VDC supply inside your TC, if you don't have one already condsider adding a shunt and battery monitor (Trimetric, Xantrex, and others )to get the most lifetime out of your expensive batteries. A good monitor will also let you know when you will need to recharge your batteries to avoid waking up in the middle of the night with the heater just blowing cold air or the LP gas detector sounding due to low voltage.
