Smart-UPS RT 3000 XL with rapid change and low voltage?

Anonymous user · ‎2021-07-07

I am not sure why this is happening???

Data Center in a shop environment. Every couple of weeks I get a ton of emails from one of my 3000's that it has switched to battery power for this: "On battery power in response to rapid change of input." or this: "Bypass not in range ; low voltage." I have two 3000's but the other doesnt seem to have any issues. Not sure if it makes a difference, but the one with no issues breakers are in a different electrical panel. I have attached the logs and data. I would certainly appreciate if anyone can shed some light.

Thanks!

other info:

Last Battery Transfer:	Unacceptable utility voltage rate of change
Battery Temperature:	27.8°C
Runtime Remaining:	1hour 12min 12sec
UPS Input
Input Voltage:	215.5 VAC	@ 60.0 Hz

UPS Output
Output Voltage:	208.0 VAC	@ 60.0 Hz
Load Current:	8.5 Amps

Output VA:	59.2 %
Output Watts:	83.4 %
Battery Status
State of Charge:	100.0 %
Battery Voltage:	218.3 VDC
Num of External Batteries:	1

Model:	Smart-UPS RT 3000 XL
SKU:	SURTD3000XLT
Serial Number:	QS1402270771
Firmware Revision:	5.1 (ID5)
Manufacture Date:	01/08/2014

Apparent Power Rating:	3000 VA
Real Power Rating:	2100 W

BillP · ‎2021-07-07

Hi,

The rapid change in voltage is listed a little bit here -> http://www.apc.com/support/index?page=content&country=ITB〈=en&locale=en_US&id=FA156546

Depending on how fast it is actually happening, the data log may not be able to catch it so it may not be obvious. I do see a few brief periods where your input voltage is dipping a little lower than it usually is in the Vmin column in the data log.

Bypass not in range messages are generated whenever the AC input voltage goes outside of the acceptable bypass criteria. Some of these settings are available to check in the Configuration->Power Settings in the management interface. This means that if your UPS needs to go to bypass while that alarm is active, it won't be able to. A UPS of this type will go to bypass because of like a fault or overload type condition. Normally, if a fault or overload occurs, the UPS will try to go to bypass (AKA run off of utility power) as to keep your load up rather than turning off completely.

I hope that helps clarify. Regardless, if it is frequent and happening regularly, it is an issue with utility power or something at that panel. A dip in voltage could indicate a high current draw on that panel/phase/circuit if it is not happening on the other panel. It may require an electrician to review but the UPS is just alarming to you that there is a problem and there is not much that can be done by the UPS besides alarm you. I don't see anything here that would point to the UPS causing the issue as the alarms refer to something going on with input utility power to the UPS.

I am not saying to go definitely spend money and do this but for situations like this, it may be helpful to leave a meter or oscilliscope running off of this panel or input feed to the UPS in order to see if it shows any abnormalities in the waveform showing the voltage drops. The UPS doesn't have the ability to capture waveforms or anything itself unfortunately.

See Answer In Context

BillP · ‎2021-07-07

Hi,

The rapid change in voltage is listed a little bit here -> http://www.apc.com/support/index?page=content&country=ITB〈=en&locale=en_US&id=FA156546

Depending on how fast it is actually happening, the data log may not be able to catch it so it may not be obvious. I do see a few brief periods where your input voltage is dipping a little lower than it usually is in the Vmin column in the data log.

Bypass not in range messages are generated whenever the AC input voltage goes outside of the acceptable bypass criteria. Some of these settings are available to check in the Configuration->Power Settings in the management interface. This means that if your UPS needs to go to bypass while that alarm is active, it won't be able to. A UPS of this type will go to bypass because of like a fault or overload type condition. Normally, if a fault or overload occurs, the UPS will try to go to bypass (AKA run off of utility power) as to keep your load up rather than turning off completely.

I hope that helps clarify. Regardless, if it is frequent and happening regularly, it is an issue with utility power or something at that panel. A dip in voltage could indicate a high current draw on that panel/phase/circuit if it is not happening on the other panel. It may require an electrician to review but the UPS is just alarming to you that there is a problem and there is not much that can be done by the UPS besides alarm you. I don't see anything here that would point to the UPS causing the issue as the alarms refer to something going on with input utility power to the UPS.

I am not saying to go definitely spend money and do this but for situations like this, it may be helpful to leave a meter or oscilliscope running off of this panel or input feed to the UPS in order to see if it shows any abnormalities in the waveform showing the voltage drops. The UPS doesn't have the ability to capture waveforms or anything itself unfortunately.