question

lief ryan avatar image
lief ryan asked

Multiplus charge current isn't reaching its potential maximum?

i'm charging my batteries from a generator on Ac input- 1, it won't charge at more than 21 A DC even though i have set the DC charge limit to 35A, i have also played with the AC current limit but it still won't charge at a higher current, any ideas?

(Multiplus 48/3000/35-16 230V, pylontech us2000b x2)

Thanks

Lief.

@Guy Stewart (Victron Community Manager)

MultiPlus Quattro Inverter Chargercurrent limit
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4 Answers
Guy Stewart (Victron Community Manager) avatar image
Guy Stewart (Victron Community Manager) answered ·

Hi @lief ryan,

The common cause of loss of maximum charge power is enabling the Weak AC setting in the Charger Tab of VEConfigure.

There is more explanation about why this is the case here:

https://www.victronenergy.com/live/multiplus_faq#derating_of_the_power_factor

It is recommended to try disabling the Weak AC setting, and trying to improve the AC supply quality if you want to increase charge power. However, be aware this may result in no charging at all.

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lief ryan avatar image lief ryan commented ·

thanks, i'll try disabling Weak AC, i did enable it before because i had a poor quality generator and was struggling to get it to connect , i have now invested in a better, more powerful generator so hopefully i'll get a better charge rate.


Thanks again.

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offroadflow avatar image offroadflow lief ryan commented ·
@lief ryan

Did "weak ac off" solve the problem?

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petajoule avatar image
petajoule answered ·

For more (or any) ideas, need more info:

What capacity does the generator on your AC IN-1 have and what is your battery voltage (and chemistry).

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lief ryan avatar image lief ryan commented ·

5kw generator and 48v lithium (pylontech) , i can charge at 50A from the solar charge controller so it shouldn't be a battery limit.

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petajoule avatar image petajoule lief ryan commented ·

Doesn't look like a battery limit, but the solar charge controller is a DC-DC charger independent (I assume) of the Multiplus. In which case the next question would be what type of Multiplus you have and with what current it can charge the batteries if you have it connected to mains.

Also make sure you read https://www.victronenergy.com/live/multiplus_faq

Generator capacity is often on the optimistic side, so a 5KW Genset may actually be able to provide much less (sure it is 5KW and not 5kVA?). I also still don't know if you are on a 120 or 230V system.

Quote from the article linked above:

A reasonable starting point for the AC Current input limit is 80% of the generator capacity in Watts. For example:


a 5kVA generator typically provides about 4 kW

80% of 4 kW is 3200 W

3200 W / 230 V volts = 13.9 A

Set the AC Current Input Limit to 13 A


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lief ryan avatar image lief ryan petajoule commented ·

i have a multiplus 230v 48/3000/ 16-50 so it should be able to charge at more than 5-6A AC, the generator is capable of 20A ac (20x230=4600w) but like i said it doesn't seem to matter how high i set the AC or DC charge current limit it will only charge batteries at about 20A DC

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Tom avatar image
Tom answered ·

What Multiplus do you have? I have the 24/300 70-50 110VAC unit with the charge current set at 70 amps and I only get a max charge on a 30 amp circuit of 54 amps charging even though I am only using 14.4 amps of input from the 110vac. I am assuming I need to have a 50 amp service to get a full 70 amps of charging. Also the resistance if the type of batteries and temperature of the batteries may reduce the charging amps.

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ystwyth1 avatar image
ystwyth1 answered ·

I have had this same problem for a day or 2 and found my battery profile was not set for lifepo4s i had set them manually, this made it charge at 30amps after setting it to lithium in the presets went up to 50amps and has been running fine. for some reason using user setting backs off the amps

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