Mains frequency is too low
Hi
This is Engineer Majid , from Iraq .
I own an APC 1500 ups , the problem is that the utility power is always at 45Hz , causing my ups to work on backup mode all the time
Is there any way or modification to reduce this frequency sensitivity feature ?
Thanks
Is this a good question?
5 Comments
Hi, Have you asked the Utility why their supply frequency is low? It must be affecting everybody, e.g. electric clocks would run slow, electric timers would be inaccurate etc. Surely they must be aware of this.
by jayeff
jayeff,
Thank you for your reply , I called it (utility) because it is a diesel generators that supply each tens of houses , and we rely on them , because the REAL utility power is a disaster ! , and yes , I've asked him many times ! it's a way of cheating as well ! so I decided to modify my APC electronically , and I've all schematic diagrams since I'm an engineer , I don't know the way of frequency sensing , either by (Averager) circuit or directly by microprocessor .
by majidsarah
Hi, Not sure if this is the manual for your UPS or not. if it is, have you tried adjusting the "local power setting " to 'poor' as shown on p.8 to see if this makes a difference? Apologies if you have tried this already. http://www.farnell.com/datasheets/199202...
by jayeff
Thank you Sir , I tried this many years ago ,the APC won't accept less than 47Hz , so I need an electronic interference !.
by majidsarah
Hi, Your problem is above my competency level but have you tried contacting the manufacturer of your UPS and asking them what you would have to modify so as to get your UPS to accept 45Hz if the 'local power setting' is set to 'poor'? See the manual in the above link for the contact details for support.
by jayeff