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renogy 50 amp dcdc mppt can't get alternator light to turn on

Benihanas

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I just set up my system for the first time in my JDM rv and everything works / comes on except for the alternator light... I don't have the panels hooked up yet but to the best of my knowledge I can and should do that last ( or at least after the battery) the battery light comes on and the inverter works fine ( I have wills 400 watt w alternator set up almost exactly but with a 2000w inverter and proper breakers/ wires for that) I have a 4 gauge wire running from a 70 amp breaker down to my battery about 4 feet and hooked directly to the positive lead... not sure what the issue might be but would love some help
 
Does your Renogy DCC require an IGN feed to signal it to turn on? Or is it a smart alternator sensing version?
thanks for the quick reply Mr. Sandals! it has a smart IGN wire but it is a smart sensing version and my camper is a Japanese elf 150 ox.. it is a small 3.1 liter Diesel engine with an 80 amp 12 v alternator
 
it has a smart IGN wire
I don't know what a smart wire is! My understanding of an IGN wire is that it has 12V on it when ignition is on. There is usually a delay before the DCC starts so that you are able to start your engine beforehand.

So what is the voltage you measure at the DCC when the alternator is running? It should say in your manual what voltage it requires to start charging.

Sorry i do not have experience with your rig, alternator or even that DC-DC charger (only Victron Orion).
 
What happens when you apply 12V to the IGN wire? If you have a 12V circuit nearby (cigarette lighter?) maybe you can use this to turn your DCC on.
no worries... im a newbie so I don't have a voltmeter on hand atm and the dcdc has a IGN wire that is only for smart alternator it is supposed to be able to run a standard alternator just fine on its own and sense the voltage automatically at 13.7
 
no worries... im a newbie so I don't have a voltmeter on hand atm and the dcdc has a IGN wire that is only for smart alternator it is supposed to be able to run a standard alternator just fine on its own and sense the voltage automatically at 13.7
I am not sure thats right.
I think the IGN wire is not for smart alternators but rather for a hard wired start from a wire that gets 12V when the ignition is on. Thats why its for an IGN (ignition) 12V signal. So no smarts involved.

A smart DC-DC charger senses that the voltage has increased (i think Victron Orion figures something over 14V) which means the alternator has started and commences charging after a delay.

Thats my understanding. I don't know what a smart alternator would do to your DCC.
 
I am not sure thats right.
I think the IGN wire is not for smart alternators but rather for a hard wired start from a wire that gets 12V when the ignition is on. Thats why its for an IGN (ignition) 12V signal. So no smarts involved.

A smart DC-DC charger senses that the voltage has increased (i think Victron Orion figures something over 14V) which means the alternator has started and commences charging after a delay.

Thats my understanding. I don't know what a smart alternator would do to your DCC.
will has a video about the dcdc and he seems to be running it fine without running that wire.. I believe the mppt can sense when the stater battery voltage goes over 13.7 on its own (according to the manual at least)
 
will has a video about the dcdc and he seems to be running it fine without running that wire.. I believe the mppt can sense when the stater battery voltage goes over 13.7 on its own (according to the manual at least)
Well, the MPPT is on the solar input. I have one of those chargers and I do not use the IGN. Don't know if it is exactly the same as yours. Get a meter, we don't even know for sure if the power is getting to the unit.

On another subject, pulling 60 or so amps from your 80 amp alt plus whatever the vehicle is using is asking a lot. I wouldn't run it at an idle for sure.
 
Well, the MPPT is on the solar input. I have one of those chargers and I do not use the IGN. Don't know if it is exactly the same as yours. Get a meter, we don't even know for sure if the power is getting to the unit.

On another subject, pulling 60 or so amps from your 80 amp alt plus whatever the vehicle is using is asking a lot. I wouldn't run it at an idle for sure.
meter will be here tomorrow.. I think the dcdc only pulls like 50 max and then levels out even more depending on any solar input you're getting.. im not planning on running it on idle out boon docking I just wanted to test it but I did drive it around the block to see if anything kicked on and no dice... could it be because the old house batteries are still connected?
 
Well, it puts 50 amps into the battery. Since the controller is not 100% efficient it draws more than 50 amps to do so. If we assume 80% efficiency, that is 60 amps. Even 50 amps is a mighty load on an 80 amp alt. Don't forget the car is pulling a decent amount of juice too. Yes, if you have any solar input at all it will drop the alt input to 25 amps.
 
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