Victron Orion DC-DC strange interaction with alternator

[mantis_solar]

I have installed an Orion 12/12-30 Isolated in my trailer connected to my Toyota Highlander with the tow package and 150a smart alternator. I'll be having upgraded 6 AWG run next week from the alternator to the trailer, but to start with I've just hooked it up to the 10 AWG power wire in the 7 pin connector. It comes up fine in Victron Connect, shows 12.8 volts from the battery with the car off. I turn the car on, I get 14 volts, the Orion detects it and starts charging. But then the input voltage starts dropping steadily and then drops enough for the orion to turn off. It stays at zero whether or not the car is running until I unplug the 7 pin. I plug back in and it comes up again, then tails off again. If I disconnect the power wire from the Orion and measure it, it stays at 14v with the car on. Anyone have any idea what the interaction between the Orion and the car power system is that is causing this?

 

[justinm001]

Sounds like your 7pin wiring on the truck side isn't nearly strong enough. When the Orion starts to pull 30a it drops the voltage then shuts off. 30a is the limit for the 7pin plug but most trucks only send 10amps or something and thin wiring.

 

[0truck0]

Im not sure how the Orion behaves, but if your battery is fully charged, then will the Orion drop voltage then turn off when battery is at 100%?

Often RVers are concerned that the charger is not putting out its max rated voltage and the answer is usually because the charger is in Float mode.

 

[justinm001]

Im not sure how the Orion behaves, but if your battery is fully charged, then will the Orion drop voltage then turn off when battery is at 100%?

Often RVers are concerned that the charger is not putting out its max rated voltage and the answer is usually because the charger is in Float mode.

If normal Orion (not smart). It has a manual dial and will output whatever voltage it's set to as long as it's getting enough voltage coming in.

If smart then it can get down to like 7v and there's all kinds of options to shut down voltages and such.

But regardless if the wiring is too thin trying to pump 30a when it's rated for 10a will cause it to drop voltage very low and the DC converter will shutoff and not blow the fuse

 

[mikefitz]

Orion 12/12-30 Isolated

If you have the Orion tri smart the cut in and cut out voltages can be user programmable.

 

[Vigo]

Justinm001 has got it, i think. You are causing enough voltage drop through the undersized wiring that input voltage (at the Victron) falls below the minimum and the unit shuts off. Voltage drop is proportional to current flow so once the current stops, the voltage drop disappears and you are back up to 14v.

If the Victron has an adjustable current limit you could probably find a current level that would not result in hitting low voltage shutdown, but i would expect it to be a pretty small number given the way you're powering it. You will need that 6awg wire to get the full 30amps output from it.

 

[justinm001]

Justinm001 has got it, i think. You are causing enough voltage drop through the undersized wiring that input voltage (at the Victron) falls below the minimum and the unit shuts off. Voltage drop is proportional to current flow so once the current stops, the voltage drop disappears and you are back up to 14v.

If the Victron has an adjustable current limit you could probably find a current level that would not result in hitting low voltage shutdown, but i would expect it to be a pretty small number given the way you're powering it. You will need that 6awg wire to get the full 30amps output from it.

I believe only the new Orion XS can limit current. The "smart" ones only turn on/off at voltages and charging profiles. It's why they make multiple different amperages 10/20/30/70

10awg can handle 30a. OP could run a pair of wires from truck battery fused to the 30a pins on the 7pin and it'll work. Or just get a 20a and lose 120w.

 

[Vigo]

10awg can handle 30a. OP could run a pair of wires from truck battery fused to the 30a pins on the 7pin and it'll work. Or just get a 20a and lose 120w.

Technically yes but since most pickups are about 20ft long i think going up to the 6awg is a good idea here. Truck is still chassis ground so don't need to run a pair, just a short 6awg ground wire bolted to the frame near the rear bumper would suffice. I think it's fine to run the power and ground through the 7 pin connector as long as the actual wire sizes are sufficient to compensate for the length of the wire run.

 

[mantis_solar]

Justinm001 has got it, i think. You are causing enough voltage drop through the undersized wiring that input voltage (at the Victron) falls below the minimum and the unit shuts off. Voltage drop is proportional to current flow so once the current stops, the voltage drop disappears and you are back up to 14v.

If the Victron has an adjustable current limit you could probably find a current level that would not result in hitting low voltage shutdown, but i would expect it to be a pretty small number given the way you're powering it. You will need that 6awg wire to get the full 30amps output from it.

I'm thinking the Victron stays shut off because I have to unplug the trailer connector to get it to turn back on.

 

[Vigo]

Some devices are configurable as to whether they 'auto-restart' after a low voltage shutdown, but some aren't.. If the Victron doesn't have a setting for that then you have no choice but to try to avoid low-voltage shutdown so you don't accidentally waste a whole 'engine running trip' worth of charging time because of a shutdown you weren't aware of while underway.

 

[justinm001]

I'm thinking the Victron stays shut off because I have to unplug the trailer connector to get it to turn back on.

I believe there's an option to set restart voltage and if that's high it'll start then turn off but won't restart unless it hits that voltage.

Show a screenshot of all the settings in the app. Then set those starter side voltages to like 12v and see what happens. Maybe down to 10v

 

[HarryN]

Take a look at the input voltage side of the Orion. The smart alternator might be allowing the starter battery voltage to drop below the trigger point of the orion to turn / stay on.

 

[sshibly]

I have installed an Orion 12/12-30 Isolated in my trailer connected to my Toyota Highlander with the tow package and 150a smart alternator. I'll be having upgraded 6 AWG run next week from the alternator to the trailer, but to start with I've just hooked it up to the 10 AWG power wire in the 7 pin connector. It comes up fine in Victron Connect, shows 12.8 volts from the battery with the car off. I turn the car on, I get 14 volts, the Orion detects it and starts charging. But then the input voltage starts dropping steadily and then drops enough for the orion to turn off. It stays at zero whether or not the car is running until I unplug the 7 pin. I plug back in and it comes up again, then tails off again. If I disconnect the power wire from the Orion and measure it, it stays at 14v with the car on. Anyone have any idea what the interaction between the Orion and the car power system is that is causing this?

Op,

1. Please look up the alternator output curve, most alternators output is low at low rpm or idle.

2. Look into HIGH IDLE switch or ECU option

3. Test the same and have someone sit at the helm and raise the idle to 1300 rpm and see how the unit does,

4. Gun your alternator with a laser thermometer and see how it is heating up.

My money is that the alternator is heating up and then the system lowers the output...

 

[justinm001]

Op,

1. Please look up the alternator output curve, most alternators output is low at low rpm or idle.

2. Look into HIGH IDLE switch or ECU option

3. Test the same and have someone sit at the helm and raise the idle to 1300 rpm and see how the unit does,

4. Gun your alternator with a laser thermometer and see how it is heating up.

My money is that the alternator is heating up and then the system lowers the output...

Yes you're right that the alternator can only output so much but it doesn't matter with ops issue. If the alternator was overloaded the DC converter loads would come from the starter battery slowly draining the power until things like the stereo and engine shuts off. The DC converter can comfortably run as low as 9v.

30a isn't much power for any newer vehicle to handle. A single cigerette lighter can run like 15a and most vehicles have a few and even ac chargers built in. If it was 70a or more I could see this being an issue and possibly overloading/overheating the alt. Simple way to check is the truck should have a voltmeter on dash, maybe digital one. Just watch that and if it dips below 13v at any point there's a possible issue