howdy all,the problem i have is whenever the battery in the camper is down (usually when picked up from dealer) and there is not enough juice to raise the landing gear i plug into the truck and attempt to raise the gear and the 20amp fuse in the f-250 (with factory towing setup) blows. there was not even enough power to start the Genset before the fuse blew. i would think that the dual battery in the truck would at least start the gen but it just clicketyclicks and i assume the gear draws more than 20 amps. i tried a 30amp and it blew, so as i needed to drop the trailer so i could get to the airport i bridged the fuse and lowered the gear(using short bursts as not to heat up the wires).So, how do i get more power to the camper? or is the system just not meant for this type of operation (power camper 12dvc systems from truck 12vdc i did use the high idle switch on the truck for max amps )Thanks JJ
20 amp fuse for 12vdc to trailer blows on tow rig.
- Thread starter JJandDD
- Start date
I would install a battery cutoff switch.
There is always some parasitic draw when you are not plugged in that cause battery drain.
Your battery should remain charged while in storage if there is no drain
Or as an option disconnect the neutral cable.
Peace
Dave
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There is always some parasitic draw when you are not plugged in that cause battery drain.
Your battery should remain charged while in storage if there is no drain
Or as an option disconnect the neutral cable.
Peace
Dave
Sent from my DROID RAZR using Tapatalk 2
evolvingpowercat
Well-known member
I assume you have a 7-way trailer connector. If the F250 had a 20 Amp fuse the wiring to the 7 way connector is likely only good for that many amps continuous and not have the factory wire inside the F-250 heat up too much. You should be fine doing the "short bursts" thing with up to a 2X bigger fuse and cause no harm to the F250. Just remember to put back the 20 A fuse when you are done.
For this "occasional use" situation I suggest you consider buying a length of 8 AWG stranded (use 6 AWG if length is more than 50 feet, which I assume it is not) that would reach from your battery on your F250 to the battery on your 305 and put a large clamp on connector like what are on jumper cables on both ends and just "jumper the two battery plus 12V lugs together when needed. That will be a lower resistance path between the two batteries so it should take most of the current and keep you from blowing the 20A fuse when you operate large loads (slide, landing jacks) one at a time on the RV supplemented with F250 power when the RV batteries are down. You should not have to jumper the ground side for your purposes, if you only plan to use when the 7-way is plugged in to complete the ground path. Put a 40 Amp Fuse in line just to make sure you are protected from "oops" situations where you accidently put battery on one end and ground on the other end, and because it would not be OK to run more than 40 Amps thru the ground connection on the 7-Way, likely that the F250 side is not sized to handle more than that without risk of harm.
For this "occasional use" situation I suggest you consider buying a length of 8 AWG stranded (use 6 AWG if length is more than 50 feet, which I assume it is not) that would reach from your battery on your F250 to the battery on your 305 and put a large clamp on connector like what are on jumper cables on both ends and just "jumper the two battery plus 12V lugs together when needed. That will be a lower resistance path between the two batteries so it should take most of the current and keep you from blowing the 20A fuse when you operate large loads (slide, landing jacks) one at a time on the RV supplemented with F250 power when the RV batteries are down. You should not have to jumper the ground side for your purposes, if you only plan to use when the 7-way is plugged in to complete the ground path. Put a 40 Amp Fuse in line just to make sure you are protected from "oops" situations where you accidently put battery on one end and ground on the other end, and because it would not be OK to run more than 40 Amps thru the ground connection on the 7-Way, likely that the F250 side is not sized to handle more than that without risk of harm.
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evolvingpowercat
Well-known member
I had done a calculation and figured out that the drain from the LP gas leak detector, Carbon Monoxide detector, refrigerator, control board on water heater, 12V audio system, etc. draw enough current to drain the RV batteries below 50% in two weeks and will totally discharge them in about 4 weeks. 50% is the level that batteries are recommended to be kept above to maximize their life. 12 Volt cut-off switch will stop the slow discharge when stored, but keep in mind that your refrigerator can not run even in LP mode with no 12V present. So if you install a cutoff switch keep that in mind, you will have to make sure you put your refrigerator in to storage mode and leave the doors open to allow them to dry out to prevent mold and smells when ever you operate the cut-off switch.
thanks guys for the input. i do have a cut off switch and use it for storage. the dealer is the one who leaves things on while it sits waiting for parts. then when i pick it up the bat is dead and they jump it to raise the gear. of course i have already blown the fuse by this time so no charge while driving home. i think i will carry plenty of fuses in my kit, and make a direct cable to the bat that i can plug jumpers into at the rear like a tow truck has.
thanks
JJ
thanks
JJ
wdk450
Well-known member
A couple of points:
Your batteries may be no longer much good, due to being repeatedly deep discharged. Its just like your car batteries - Leave the lights on a few times (you can't do that any more with most newer cars) and the battery becomes unable to take a full charge. I'm thinking about adding a small solar panel just for storage and the parasitic load question.
Second, the guy talking about running one seperate, larger gauge wire from the truck battery to the trailer batteries, forgot that this greater charge current than the normal truck wiring is rated for has to be returned to the truck battery through the normal small guage truck ground wiring. This will restrict the current flow and cause heating in the ground wire from the truck connector to the truck chassis. This probably also exceeds the current rating for the connector pins, causing that connector ground pin to heat and corrode. A bad ground connector pin to your trailer can cause lighting and braking problems. You need to run 2 higher current wires to your trailer from the truck. You can probably use the truck frame as part of the circuit.
Your batteries may be no longer much good, due to being repeatedly deep discharged. Its just like your car batteries - Leave the lights on a few times (you can't do that any more with most newer cars) and the battery becomes unable to take a full charge. I'm thinking about adding a small solar panel just for storage and the parasitic load question.
Second, the guy talking about running one seperate, larger gauge wire from the truck battery to the trailer batteries, forgot that this greater charge current than the normal truck wiring is rated for has to be returned to the truck battery through the normal small guage truck ground wiring. This will restrict the current flow and cause heating in the ground wire from the truck connector to the truck chassis. This probably also exceeds the current rating for the connector pins, causing that connector ground pin to heat and corrode. A bad ground connector pin to your trailer can cause lighting and braking problems. You need to run 2 higher current wires to your trailer from the truck. You can probably use the truck frame as part of the circuit.
