Frequency output on SURT10000RMXLI

[vvv850_apc]

This was originally posted on APC forums on 8/2/2013

---

Hello,

I am trying to better understand the reason for having the option to select between +/- 0.1 and +/- 3 Hz for output frequency.

Currently our UPS is set to auto and is powering our server Rack. The nominal frequency in our country is 50Hz. We also have a backup generator which has an output frequency between 52Hz and 50Hz depending on the load.

Everything works well even on the genset but I wanted to know what are the implications of setting the output frequency to 50 +/- 0.1 or 50 +/- 3 from auto. Why would anyone want +/- 3 Hz output?

Regards.

[BillP]

This reply was originally posted by Angela on APC forums on 8/2/2013

---

I think it just really depends on the install environment and load attached as far as how narrow or wide a user wants to allow their output frequency to fluctuate.

[vvv850_apc]

This was originally posted on APC forums on 8/2/2013

---

Ok, but why let the user decide the range of the output frequency if it is better to have a narrow fluctuation of +/- 0.1Hz than a wider +/- 3Hz frequency without any other considerations.

The reason I am asking is that I believe that there must be something to take into account if for example you have an output setting of +/- 0.1 Hz and suddenly your input goes above reaching 52Hz as when using a generator without too much load. Then the UPS should continue outputting 50 +/- 0.1 Hz but maybe? not be in online mode anymore thus not conditioning the output voltage.

[BillP · Accepted solution]

This reply was originally posted by Angela on APC forums on 8/2/2013

---

Did some more checking.

This option would also give you a broader range of when bypass operation would be available. If the frequency is "out of range" for bypass functionality and the UPS needs to go to bypass due to a fault or overload, it will drop the load.