I have a new Ford Ranger with a 220amp alternator. I fitted a Victron 50amp dcdc charger to charge the 3 AGM 100amp batteries in my Rockwood TT.
The max charge I get is around 25amps.
Why is this ?
Have 1/4” od copper wire from truck battery to dcdc
We need more.information to be able to help here. When the charger is running grab a screenshot of the settings page and the status page.
Does your vehicle have a smart alternator that reduces its output voltage to very low values.
What cable lengths do you have in and out and what do you mean by 1/4" OD, is this just the copper or over the insulation, ideally what is the awg.
I could make lots of guesses but some more info would be very useful. Possible causes
- Poor/loose connections on the wiring.
- Low alternator voltage either by design (smart alternator) or failed alternator.
- Too much voltage drop on the input or output wires or use of cheap thermal breakers with high contact resistance.
- Overheating and throttling back.
- The batteries are close to full.
The positive wire from the truck battery to the 50amp Anderson plug next to the tow ball and from there to the dcdc charger mounted next to the house batteries on my Rockwood TT are 6AWG. The earth wire from the Anderson plug to the dcdc is also 6AWG. I used the truck chassis
as the earth on the truck with 6AWG tails on each end.
I was careful with ensuring all terminals were tight.
I had the Dealer reprogram the truck to two batteries, one sensing which is the correct setup I believe. This adjusts the smart alternator for charging auxiliary batteries.
I have 3 agm batteries at 100 amp hours.
Overnight the Victron records the batteries are generally discharged to about 80%.
The max charge I’ve seen running the truck engine is around 25amps. I set the Victron 50amp dcdc to 40 amps and was hoping to see it charging the house batteries at 40 amps!
Peter
Just had a look at your vehicle and trailer brands, they are impressive and not something we are used to here in Europe.
The 6AWG has a large enough current capacity for the Orion XS. If I was to choose a reason based on your description it would be voltage drop on the input of the Orion due to the length, multiple connections and Anderson plug. The engine shutdown detection on the Orion has a default setting of 13.2V (if I remember correctly) for shutdown, if the voltage at the Orion falls to this it throttles the current to maintain this voltage. You could reduce this to say 12.8V to 12.9V, or you could swap to an ignition switch signal if you have an ignition signal relayed to the trailer. Checks are, when charging, use a multimeter for the vehicle battery voltage and the voltage at the Orion input, or use the Victron app for this, if the Orion is sat at the shutdown voltage then it is being trimmed back to match this.
Thanks for the info.
I’m currently in the US, but the truck and TT are in New Zealand. The truck is a 2022 Ranger Wildtrack V6 diesel, with 10 speed auto.
The caravan is a Rockwood 2604SW, 3400 kg inc 460 kg on the tongue. The diesel Ranger is a great tow vehicle for this combination. I’m sure Americans will have a contrary view, but we do things a bit different due to vehicle laws, ie never tow faster than 55mph etc.
It will be October before I’m back in NZ to check your suggestions, which I very much appreciate.
Thanks again
Peter
For shutdown voltage I meant to say 12.8 to 12.9V as that is just above a full lead acid voltage so it will stop the Orion taking anything out of the input battery. It is harder setting them up with input voltage drop.
Sorry I don’t know what that means, please explain in very simple terms
Thanks
If you have engine shutdown detection on the Orion active and set the shutdown voltage to say 12.4V, when you turn the engine off, the Orion will continue to discharge the engine battery until it reaches 12.4V, which is not good. The shutdown voltage needs to be no lower than the fully charged engine battery voltage of 12.8V so the Orion does not discharge it with the engine off.
The second point about voltage drop making settings harder is because to get full 50A charge, you may need a voltage at the Orion of 12.4V because of the cable loss, but you can not set this due to discharging your battery. If you do find voltage drop you may use thicker cable.