Hi, I have an APC Back-UPS CS650 which outputs a stepped sine wave, and works perfectly with my passive PFC power supply. I'd like to know if it will work with newer PSU's which have active PFC.
There are a lot of discussions on the internet which suggest that active PFC PSU's work only with true sine wave UPS'es or only some will work with stepped sine wave PSU's.
According to APC knowledge base ( http://nam-en.apc.com/app/answers/detail/a_id/8883/kw/drops%20loadHello ) there can be a gap in output voltage that lasts up to 8ms when the external power fails, and this causes the PSU to drain its maximum power which overloads the UPS. So does that mean if a PSU can handle more than 8ms gap in the input, then it will be fine with the UPS?
For example according to the specification the FSP400-60APN has an OUTPUT VOLTAGE HOLD-UP TIME of 16.0 mS minimum (at 230V / 50 Hz, 80%LOAD).
What do you think?
There are a lot of discussions on the internet which suggest that active PFC PSU's work only with true sine wave UPS'es or only some will work with stepped sine wave PSU's.
According to APC knowledge base ( http://nam-en.apc.com/app/answers/detail/a_id/8883/kw/drops%20loadHello ) there can be a gap in output voltage that lasts up to 8ms when the external power fails, and this causes the PSU to drain its maximum power which overloads the UPS. So does that mean if a PSU can handle more than 8ms gap in the input, then it will be fine with the UPS?
For example according to the specification the FSP400-60APN has an OUTPUT VOLTAGE HOLD-UP TIME of 16.0 mS minimum (at 230V / 50 Hz, 80%LOAD).
What do you think?