Can an MPPT Controller use an Alternator as an Input?
- Thread starter Bob B
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Its a dc-dc charger for a reason. It takes lower voltages and ramps it up. And a charge controller takes higher voltages and lowers them.
Your alternator only outputs 14.4v before you run 10ft of wiring. Theres not enough voltage to charge. You can power an inverter and a dc power supply at 16v+ into a controller.
Your alternator only outputs 14.4v before you run 10ft of wiring. Theres not enough voltage to charge. You can power an inverter and a dc power supply at 16v+ into a controller.
Bob B
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OK, I just looked at the specs for for one of the Victron MPPT controllers. It shows the NOMINAL voltage for a PV array to be 12V ... with a max of 100V.
So .... it seems that the MPPT is capable of some boost or the nominal input would be higher. Still not understanding why this wouldn't work. Think I will send Victron an email.
So .... it seems that the MPPT is capable of some boost or the nominal input would be higher. Still not understanding why this wouldn't work. Think I will send Victron an email.
If you take a look at their datasheet (for example their smaller SCCs) their 'Nominal PV Power' has a footnote, thus:
Meaning that you'd need 12V + 5V = 17V before the unit will even switch on. And if you did manage to 'trick' the charger to turn on, to charge at 14.4V you'd need 15.4V on the input.
In short, as @Ped says, "No".
Additional note: And these chargers have the lowest input-to-output voltage differential I've seen anywhere - most other SCCs are 2-5V.
Edit: Added additional note.
Meaning that you'd need 12V + 5V = 17V before the unit will even switch on. And if you did manage to 'trick' the charger to turn on, to charge at 14.4V you'd need 15.4V on the input.
In short, as @Ped says, "No".
Additional note: And these chargers have the lowest input-to-output voltage differential I've seen anywhere - most other SCCs are 2-5V.
Edit: Added additional note.
Bob B
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@tictag I just went and looked at that spec again, and the footnots IS listed beside the nominal voltage spec .... as 1b... It seems that you have to be +5V for the charge to start and +1V for the charge to continue.
Here's a cut and paste from the spec sheeet:
1b) The PV voltage must exceed Vbat + 5V for the controller to start. Thereafter the minimum PV voltage is Vbat + 1V
What I was really hoping for is to use a Victron Easy Solar system to control all the charging sources. I guess it would still be possible to do that, but I would need to have a DC-DC converter between the vehicle charge system and one of the Easy Solar PV inputs.
Here's a cut and paste from the spec sheeet:
1b) The PV voltage must exceed Vbat + 5V for the controller to start. Thereafter the minimum PV voltage is Vbat + 1V
What I was really hoping for is to use a Victron Easy Solar system to control all the charging sources. I guess it would still be possible to do that, but I would need to have a DC-DC converter between the vehicle charge system and one of the Easy Solar PV inputs.
I really wouldn't recommend using a SCC to charge a battery from an alternator source, for a start, an MPPT SCC will try to find the maximum power point of the supply by varying the effective load presented to, in this case, the alternator. What this would do to an alternator is unknown to me.
You're going to need a DC-DC converter anyway, why not just buy a DC-DC charger? Victron have their 'Orion' range designed for exactly this purpose i.e. charging a 'service' battery from an alternator/starter battery source. Check out here.
There will not be a problem having two charging sources i.e. alternator & solar, you'll even be able to program which has priority.
You're going to need a DC-DC converter anyway, why not just buy a DC-DC charger? Victron have their 'Orion' range designed for exactly this purpose i.e. charging a 'service' battery from an alternator/starter battery source. Check out here.
There will not be a problem having two charging sources i.e. alternator & solar, you'll even be able to program which has priority.
Bob B
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I am looking to have better control of the charge current and voltage by having 1 unit manage Alternator, AC, and solar instead of having 3 independent charge sources landed on the battery. I want to be able to cut off the charge voltage and load independently and the Easy Solar and a Samlex inverter charger i am looking at have remote control capabilities.
The Samlex has an inverter charger that has AC charging and will combine it with a SCC. It is pretty nice, because it will also accept a generator input as well as AC from a grid tie and manage those as well. It will manage the total charge current and keep it at whatever number I set .... up to 50A if I am remembering correctly.
I am using a Chargery BMS, so I can set the min and max voltage with it and remotely shut down charge and load. It would be nice to be able to do low current switching to 1 device instead of trying to shut down multiple devices.
I would like to have the fewest # of devices possible. I looked at the MPP all-in-one that Will recomments, but don't think there is a way to stop the charging with it independently of the load.
I have more battery capacity than i think i will need and would like to cycle it at less than full capacity .... most of the time.
The Samlex has an inverter charger that has AC charging and will combine it with a SCC. It is pretty nice, because it will also accept a generator input as well as AC from a grid tie and manage those as well. It will manage the total charge current and keep it at whatever number I set .... up to 50A if I am remembering correctly.
I am using a Chargery BMS, so I can set the min and max voltage with it and remotely shut down charge and load. It would be nice to be able to do low current switching to 1 device instead of trying to shut down multiple devices.
I would like to have the fewest # of devices possible. I looked at the MPP all-in-one that Will recomments, but don't think there is a way to stop the charging with it independently of the load.
I have more battery capacity than i think i will need and would like to cycle it at less than full capacity .... most of the time.
ghostwriter66
"Here - Hold my Beer"
If you go DC-2-DC, which i recommend you want to make sure you get a good solid US one -- We love for ppl to use those cheap Chinese DC-2-DC converters at work and then put a good constant load on them ... this allows for our boredom to be interrupted by the local VFD trying to get to the burning vehicle on time before the well-head or something catches fire -- they never make it of course -- but it kills a couple of hours of the day with free entertainment ... also typically when we hear the fire alarm at work someone puts a bag of popcorn in the microwave on the way out just in case its a truck fire ... and if so we go back - get the popcorn and our chairs - sit outside and try to figure out what part from China caused the fire ... 
Bob B
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@ghostwriter66 .... do you have a link to one you like?
Sgt Raven
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Are there anymore made in the US, or is it designed by a US company but made in China?If you go DC-2-DC, which i recommend you want to make sure you get a good solid US one -- We love for ppl to use those cheap Chinese DC-2-DC converters at work and then put a good constant load on them ... this allows for our boredom to be interrupted by the local VFD trying to get to the burning vehicle on time before the well-head or something catches fire -- they never make it of course -- but it kills a couple of hours of the day with free entertainment ... also typically when we hear the fire alarm at work someone puts a bag of popcorn in the microwave on the way out just in case its a truck fire ... and if so we go back - get the popcorn and our chairs - sit outside and try to figure out what part from China caused the fire ...
My DC-DC/MPPT is from a Canadian company, but I don't know it was designed or made.
ghostwriter66
"Here - Hold my Beer"
Well to be honest, I think that they are all made in China ... BUT I guess what i am trying to say is get one thats made in China BUT to US manufacturers specifications ... at least there is some hope that at least its going to do what it says it will do ...
thedodgersonline
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Hi
Have you looked at the RedArc BMS system - has AC / DC to DC and Solar input all in one. Used extensively here in Australia. Have a presence globally. Only drawback is the low VoC max of the solar input. It has a "Green Option" which lets it use both Alternator and MPPT or can switch between the two depending on which is the most effective
Link here https://www.redarc.com.au/the-manager30
If you are looking for a static solution look at the MPPSolar range of products https://www.mppsolar.com/v3/
Regards
Wellydex
New Member
I didn't realize the US
I didn't realize that the US was the only place in the world that designed or made good solid quality equipment. I guess I'll have to throw out all my rubbish Victron and RedArc gear as those European and Aussie engineers must be incompetent. I'll give Donald Trump a call and see what he recommendsIf you go DC-2-DC, which i recommend you want to make sure you get a good solid US one -- We love for ppl to use those cheap Chinese DC-2-DC converters at work and then put a good constant load on them ... this allows for our boredom to be interrupted by the local VFD trying to get to the burning vehicle on time before the well-head or something catches fire -- they never make it of course -- but it kills a couple of hours of the day with free entertainment ... also typically when we hear the fire alarm at work someone puts a bag of popcorn in the microwave on the way out just in case its a truck fire ... and if so we go back - get the popcorn and our chairs - sit outside and try to figure out what part from China caused the fire ...
I don't think the OP even remotely implied this. I think the message was "caveat emptor" on cheap Chinese made DC-DC converters
ghostwriter66
"Here - Hold my Beer"
Alex. I'll take "People that intentional Misinterpret things for No reason" for a $1000.
Bob B
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I had looked at them briefly but it looks like they have a 50A version of the dual input now .... will have to check them out some more. I am looking for more than the 30A the manager 30 provides.