An input voltage or frequency problem prevents switching to bypass mode

[Anonymous user]

Last night we had some external power failures (the provider was resolving an external issue) and the result is this log. Need some help with this log analysis:

1. What kind of external power can make prevent switching to bypass mode?
2. It is supposed to switch to bypass mode when the batteries are exhausted?

Thanks for any help

PD: It is a Symmetra LX 16000

11/30/2010 10:39:25 UPS: A discharged battery condition no longer exists.
11/30/2010 10:38:35 UPS: The battery power is too low to support the load; if power fails, the UPS will be shut down immediately.
11/30/2010 10:31:33 UPS: A low battery condition no longer exists.
11/30/2010 10:31:33 UPS: No longer on battery power.
11/30/2010 10:06:55 UPS: No longer in bypass.
11/30/2010 10:06:39 UPS: An input voltage or frequency problem no longer prevents switching to bypass mode.
11/30/2010 10:06:36 UPS: In bypass in response to an overload.
11/30/2010 10:06:19 UPS: An input voltage or frequency problem prevents switching to bypass mode.
11/30/2010 10:06:17 UPS: An input voltage or frequency problem no longer prevents switching to bypass mode.
11/30/2010 10:05:57 UPS: An input voltage or frequency problem prevents switching to bypass mode.
11/30/2010 10:05:56 UPS: An input voltage or frequency problem no longer prevents switching to bypass mode.
11/30/2010 10:05:36 UPS: An input voltage or frequency problem prevents switching to bypass mode.
11/30/2010 10:05:35 UPS: An input voltage or frequency problem no longer prevents switching to bypass mode.
11/30/2010 10:05:15 UPS: An input voltage or frequency problem prevents switching to bypass mode.
11/30/2010 10:05:14 UPS: An input voltage or frequency problem no longer prevents switching to bypass mode.
11/30/2010 10:04:54 UPS: An input voltage or frequency problem prevents switching to bypass mode.
11/30/2010 09:39:45 UPS: The battery power is too low to continue to support the load; the UPS will shut down if input power does not return to normal soon.
11/30/2010 09:39:45 UPS: On battery power in response to an input power problem.
11/30/2010 09:38:52 UPS: A low battery condition no longer exists.
11/30/2010 08:57:03 UPS: The battery power is too low to continue to support the load; the UPS will shut down if input power does not return to normal soon.
11/30/2010 08:57:03 UPS: On battery power in response to an input power problem.
11/30/2010 08:56:19 UPS: A low battery condition no longer exists.
11/30/2010 08:38:51 UPS: The battery power is too low to continue to support the load; the UPS will shut down if input power does not return to normal soon.
11/30/2010 08:38:51 UPS: On battery power in response to an input power problem.
11/30/2010 08:38:08 UPS: A low battery condition no longer exists.
11/30/2010 08:19:26 UPS: The battery power is too low to continue to support the load; the UPS will shut down if input power does not return to normal soon.
11/30/2010 08:19:26 UPS: On battery power in response to an input power problem.
11/30/2010 08:18:39 UPS: A low battery condition no longer exists.
11/30/2010 06:52:42 UPS: The battery power is too low to continue to support the load; the UPS will shut down if input power does not return to normal soon.
11/30/2010 06:52:42 UPS: A discharged battery condition no longer exists.
11/30/2010 06:52:42 UPS: On battery power in response to an input power problem.
11/30/2010 06:52:20 UPS: The battery power is too low to support the load; if power fails, the UPS will be shut down immediately.
11/30/2010 06:52:01 UPS: A low battery condition no longer exists.
11/30/2010 06:52:01 UPS: No longer on battery power.
11/30/2010 04:16:16 UPS: The battery power is too low to continue to support the load; the UPS will shut down if input power does not return to normal soon.
11/30/2010 04:16:16 UPS: A discharged battery condition no longer exists.
11/30/2010 04:16:16 UPS: On battery power in response to an input power problem.
11/30/2010 04:15:55 UPS: The battery power is too low to support the load; if power fails, the UPS will be shut down immediately.
11/30/2010 04:15:35 UPS: No longer on battery power.
11/30/2010 01:06:12 UPS: On battery power in response to an input power problem.
11/30/2010 01:05:31 UPS: No longer on battery power.
11/29/2010 22:29:21 UPS: On battery power in response to an input power problem.
11/29/2010 22:28:39 UPS: A power module fault exists.

Message was edited by: Booga

[Anonymous user · Accepted solution]

Thank you very much, a clear explanation, your help is much appreciated.

Booga

[BillP · Accepted solution]

Hi Booga,

The Symmetra has a few simple goals:
1) Keep the critical load powered
2) Provide conditioned power from the inverters whenever possible
3) Protect the load from receiving any poor quality power (from UPS or mains)

Therefore, at all times, the UPS evaluates the mains power to determine if it is acceptable to use in bypass mode. If the power modules are unable to provide inverter output either on-line or on-battery, the UPS will consider the option of bypass and will use it if the mains power is within an acceptable range.The power modules are able to remain on-line through a wide input range -- much wider than what the UPS would ever consider sending directly to the load.

By default, the UPS considers AC input acceptable if it is within -20% and +10% of the configured output voltage from the inverters. Frequency is also considered acceptable if it is within +/- 5Hz of the configured output frequency.

Therefore, your event log shows that at times, the input was inappropriate for bypass (outside specified range above) but the UPS was able to remain on inverter either on-line or on-battery.

If the power modules cannot operate due to exhausted battery or due to overload, the UPS will consider powering the load via bypass as long as the mains input is within the acceptable range.

[BillP]

So what shall i do if this message sill exist on the display?