using UPS for motor load

[Jacbk612]

Hello everyone, I would like to purchase a UPS to operate a large garage door motor on a multi-unit building. The motor is a 120V AC 370 w load. I am told that 2 things need to be considered: the motor requires a pure sine wave and the in-rush current of the motor must be dealt with while on battery operation. I believe one can purchase a pure sine wave output UPS and if I could estimate the motor in-rush current then I could buy a UPS big enough say 2200 KVA to handle the in-rush current, is my reasoning correct?

2. How can I estimate the in-rush current?

Thanks,

Jacques

 

[Sparky001]

Hi Jacques,

Normaly you would need to calculate the startup current 6 x In

So you have 120V - 370 W so appr. 18.5 Amps.

Frans

 

[Jacbk612]

Hi Frans, yes it semms that 6 to 7 times is a good figure. I have put in my system and it works fine, I can upload a schematic if anyone is interested.

Cheers,

Jacques

 

[Jacbk612]

I wound up buying a power inverter instaed of a UPS, the power inverter provides a modified sine wave which is good enough. Also a power inverter is much cheaper per watt than a UPS.

J

 

[Sparky001]

Good decision.

Always good to save a few Euro's or in your case dollars?

Frans