An input voltage or frequency problem prevents switching to bypass mode

[Anonymous user]

Hi

We have a Smart-UPS RT 20000 RM XL UPS Installed in our data center.
Now a days We are getting "An input voltage or frequency problem prevents switching to bypass mode" very frequently.
Can you please explain what does this Alram means? and what is current frequency threshold and how we can increase the fequency threshold.

Thanks for your help.

Regards
Malik Asif Joyia

[BillP]

Well it's hard to tell you 100 % without any details on your utility power but generally speaking it means the UPS doesn't like your utility power and if you go to bypass, it will not be able to compensate for that "bad utility". Depending on your configuration, it may drop their load if you do. If you can post your voltages from the display or provide the event/data logs, we can confirm this.

[BillP]

unfortunately, we don't have a data log old enough to match up with the latest alarm you got in the event log.

if possible, when you get this alarm next time, can you get the data log from the unit within an hour or two?

the data log is the most important here i think and it does get a erased if you power cycle the NMC or if the NMC cannot communicate with the UPS internally. just keep that in mind incase the data log isnt populated like in the log you provided.

[BillP]

Dear,

This Error is showing the input voltage is not correct or no input available. Please check the input voltage and check Frequency, Is there 50hz or 60hz. If you have a 60hz then change it to 60hz because as so in the data logs your frequency is 50HZ. Check voltage line transfer high and low sating.

Change Frequency to 60hz

Regards,E

[Anonymous user]

Dear Ashfaq

Please find attached the Log for UPS.

Bypass Upper Voltage: 253 VAC
Bypass Lower Voltage: 173 VAC

Regards
ASIF

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Message was edited by: anjoyia

[BillP]

Dear Asif,

Where is logs....?

Can you print screen of the all pages.
Please tell me where are you and what is frequency in your region.

Regards,E

[Anonymous user]

Log Attached.

[Anonymous user]

Hi

I just have attached logs, you can see it now in previous post.

We are located in Abu Dhabi, United Arab Emirates.

Frequency is 50Hz.

Attached are screenshots.


Regards
ASIF

[Anonymous user]

I think there is some issue, it doent allow to upload doc or excel files.

[BillP · Accepted solution]

Hi there,

Usually under the UPS tab/configuration/power, you should be able to see the standard frequency, you could set to 50Hz and adjust it to +/- 0.1, 3 or 10Hz. From the attached TXT file, I can see your f(Hz) is at 28Hz!?!?!?! Also the message is there because you have a single input and that one is not ok power wise. Leave the standard config of APC, call thech support to guide you how to do that.
Remember : APC stes it standards and unsless particular configurations, customer should not alter the UPS parameters.

Regards,
Mihail