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Curious Victron Question

moonlitsouls

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OK so I installed the multiplus a couple months back and it’s been working great, charges my battery really fast when I run my generator and all the 110 V circuit are working properly except for the microwave. I have 120a bMs , the microwave is pulling more than that so it shut down

How can I run the generator with the sole purpose of using the microwave?


When I turn on my generator, multiplus uses all the power to charge my batteries, if I turn on the microwave while running the generator , it’ll try to charge the battery at max and run the microwave on TOP of that

I wanted to divert that power to the microwave first and charge the batteries with the remaining power, is anyone aware of any settings that I might’ve missed? Thanks
 
You have to set the shore power limit. If you have a 2000 watt generator you set the current limit to 13.3 amps (1600watts) or what ever the max continuous current is for your generator, and that is all the multiplus will allow to be drawn from shore power. If it has to it will take the balance of whatever extra is required from the battery for a short time and once the microwave load is gone it will continue to charge the battery.

Here is a video that might help out its linked to part way through:
 
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Thanks for the reply, I tried that and it didn’t work. I change the input current, I turned on the microwave, and I’m still seeing 150 A being pulled from my battery. I also sent the multiplies to inverter only mode so that it doesn’t charge the batteries at all and still it’s not pulling the power from the generator itself
 
Thanks for the reply, I tried that and it didn’t work. I change the input current, I turned on the microwave, and I’m still seeing 150 A being pulled from my battery. I also sent the multiplies to inverter only mode so that it doesn’t charge the batteries at all and still it’s not pulling the power from the generator itself
Are you changing the charger current or the AC input limit?

I can remember if you have to for these two settings or not but are you sending them to the multiplus after you change them?
 
The key is to change the AC current limit. I have a 2000W (1600W continuous) genset and if I try to run the microwave with the inverter on, the genset will shut down. I set the AC input current limit to 15A and it did the same thing. I have to set the AC input current limit to 14 or less to get it all to work. 12A is more reliable. I have the separate control panel to set the input amps, so it's really easy but I think it's easy to do on a Cerbo display as well.
 
The key is to change the AC current limit. I have a 2000W (1600W continuous) genset and if I try to run the microwave with the inverter on, the genset will shut down. I set the AC input current limit to 15A and it did the same thing. I have to set the AC input current limit to 14 or less to get it all to work. 12A is more reliable. I have the separate control panel to set the input amps, so it's really easy but I think it's easy to do on a Cerbo display as well.

i can set the AC input current using the app, I have a 2500w generator so I tried 17amps and it didn’t work
 
i can set the AC input current using the app, I have a 2500w generator so I tried 17amps and it didn’t work
How big is your microwave? running 2000W big microwave won't do it since the instant surge is 1.5 times or more.
 
How big is your microwave? running 2000W big microwave won't do it since the instant surge is 1.5 times or more.
As long as the multiplus is set up correctly, it will easily handle the load. The generator will supply 2500w of peak power and the multiplus will supply 2400watts plus its surge capacity. Again, if the multiplus is set up correctly.
 
Not sure how your inverter works but as far as I know inverter/chargers cannot invert dc and charge with ac at the same time, it's either one or the other. When running your generator it must be able to run all current loads and whatever power is left over goes to the batteries. When your charging and loads become too much for the genny it bails and your inverter goes back into invert mode.
 
Not sure how your inverter works but as far as I know inverter/chargers cannot invert dc and charge with ac at the same time, it's either one or the other. When running your generator it must be able to run all current loads and whatever power is left over goes to the batteries. When your charging and loads become too much for the genny it bails and your inverter goes back into invert mode.

Buying a little higher end inverter charger gets you a little more:

"The MultiPlus will prevent overload of a limited AC source, such as a generator or shore power connection. First, battery charging will automatically be reduced when otherwise an overload would occur. The second level will boost the output of a generator or shore side supply with power taken from the battery."


I spent a little more and went with a multiplus for this very reason. I can just limit input current and pull the cord on a 1000w generator and forget about it until it runs out of gas. I dont have to think about load or anything. It just does its thing. If its set up properly.
 
12a input limit fixed it !!!!!

Thanks everyone !!!
Do you know what it was drawing when it was just charging before? Its weird that you had to drop it that far. At 12a input you will not be able to charge at 120amps any more. From memory to charge at 120amps I was drawing 16-17 amps of shore power.
 
12a input limit fixed it !!!!!

Thanks everyone !!!
Awesome! One thing I did was when I wasn't running a big load, I set the AC current limit @ 16A to get the most out of the genset for charging. Just have to remember to drop it back down to 12A before turning on something big. Power assist is the bee's knees.

IMG_5021.jpg
 
Awesome! One thing I did was when I wasn't running a big load, I set the AC current limit @ 16A to get the most out of the genset for charging. Just have to remember to drop it back down to 12A before turning on something big. Power assist is the bee's knees.

View attachment 79960
I just left mine at 30a for charging from
The generstor bc I didn’t really understand the concept of the limiter. Moving forward I think I’ll try 16 for charging and 12 for the microwave as well, but what about the air conditioning?

I knew that the limiter could be used when I was actually hooked up to shore power, when using a circuit that may be less than 30 A, or maybe somebody’s driveway. And I understood the powers assist function in that capacity, but frankly I’m still a little bit confused about how it even applies to the generator itself
 
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I just left mine at 30a for charging from
The generstor bc I didn’t really understand the concept of the limiter. Moving forward I think I’ll try 16 for charging and 12 for the microwave as well, but what about the air conditioning?

I knew that the limiter could be used when I was actually hooked up to shore power, when using a circuit that may be less than 30 A, or maybe somebody’s driveway. And I understood the powers assist function in that capacity, but frankly I’m still a little bit confused about how it even applies to the generator itself
My 15k BTU A/C actually draws less AC power than my microwave. Here's a pic of the display with the AC running:

IMG_5024.jpg

But I keep the AC current limit set to 12A whenever I have the genset running.

I think the reason the genset trips off with power assist is it sees an overload before the MPII can get enough assist going. If you are in ECO mode on the genset, you may never get the power assist to work well.
 
My 15k BTU A/C actually draws less AC power than my microwave. Here's a pic of the display with the AC running:

View attachment 80038

But I keep the AC current limit set to 12A whenever I have the genset running.

I think the reason the genset trips off with power assist is it sees an overload before the MPII can get enough assist going. If you are in ECO mode on the genset, you may never get the power assist to work well.
Are you running Coleman or Dometic A/C?
Also, since that looks like a Micro-air thermostat...also using their soft start as well?
 
Are you running Coleman or Dometic A/C?
Also, since that looks like a Micro-air thermostat...also using their soft start as well?
Coleman Mach 8 (x2). I have a micro-air soft start on both. I could not run one a/c on the Champion genset without the soft start. It's too cold to try right now, but I think I can run both a/c at the same time with the small genset with power assist. Not sure I will, but will be nice to try it out.
 
Coleman Mach 8 (x2). I have a micro-air soft start on both. I could not run one a/c on the Champion genset without the soft start. It's too cold to try right now, but I think I can run both a/c at the same time with the small genset with power assist. Not sure I will, but will be nice to try it out.
I have the Coleman Mach 8 , it’s a low profile 9000btu

Now that I have my 4/0 wire installed I’m gonna crank up the ac tomorrow and see if I can run it off the battery alone ?

I want to install a mini split for the summer and run that during the day , solar should cover most of it
 
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