question

muhamad avatar image
muhamad asked

a ~0.4 seconds electricity "blink" every time a 3-phase air-conditioner motor starts

I have a 3-phase off-grid Victron system (no other source of energy, only batteries), 10kva inverter each, the battery bank is 1000AH, connected by a 95mm² cable (2 meters length) to the bus bar.

the bus bar is connected to the inverters with a 70mm² cable (1.5 meters length) each.

as for the AC output, a 10mm² cable (3 meters length).


now for the issue:

the house has various led lights and electric machines such as treadmills, water cooler...etc.

there are 4 air conditioners in the house, one of them is large (see spec image below), and it's a problem! once it's large motor starts (on remote command or after a waking up from power conservation mode) there's a blink on electricity that affects all the led lights (they go off and on again in a span of ~0.4 seconds), the treadmill stops instantly (which is very dangerous!), while other devices aren't affected at all, i.e: computer screens and TVs.

this is very annoying to the owner of the house and extremely dangerous in case of treadmills usage.


I tried the change the "boost power assist" configuration (default was 2, tried 1.5 and 2.5) but it didn't help.


I'm out of ideas and I have to solve this issue asap, your input is highly appreciated.

thank you.


electraAirConditioner.PNG

3 phasequattro 10kvaaircondition
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3 Answers
kevgermany avatar image
kevgermany answered ·

From your description it's the surge current at startup of the AC. Suggest you find a surge current limiter and connect the large A/C through that

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lifeingalicia avatar image
lifeingalicia answered ·

Dont forget to check the capacitors of the hvac unit - defective may draw unessesary current.

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Trevor Bird avatar image
Trevor Bird answered ·

You could install a 3 phase motor soft start to the AC unit. You need to reduce the shock load caused by the inrush current. A soft starter will enormously reduce that.

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