Bypass not in range ; either frequency or voltage.

[mimoss03]

We've have 7 Smart-UPS SRT 5000 on various floors of our building. We've regularly have been getting these errors on different units. Typically every couple days 1 or 2 of them give us this alert.

Bypass not in range ; either frequency or voltage.

Looking at the data logs, i understand that the input voltage is dropping which would prevent the UPS from going into bypass mode if needed. My question is two-fold.

1. What can be causing this?

2. How would we go about troubleshooting and recifying?

(See line at 6:53:39)

Date	Time	Vmin	Vmax	Vout	Iout	%Wout	%out	FrqOut	%Cap	Vbat	Tups
08/22/2024	07:13:39	213.11	214.59	208.27	2.41	5.28	9.22	58.84	100.00	217.91	+22.00
08/22/2024	07:03:39	212.53	214.95	208.27	2.41	5.15	9.30	58.86	100.00	217.91	+22.00
08/22/2024	06:53:39	175.17	214.89	208.30	2.41	5.25	9.25	58.82	100.00	217.94	+22.00
08/22/2024	06:43:39	213.41	215.44	208.28	2.38	5.36	9.19	58.83	100.00	217.97	+22.00

[Teken]

Given you have provided absolutely no context or information regarding the building / facility. My reply will be generalized to encompass as many common issues.

The UPS is seeing power quality issues as it relates to the input voltage. Specifically, they are seeing a voltage sag / drift in frequency at the outlet.

There is nothing for you to do unless you have complete access, control, and knowledge of the buildings electrical system and the equipment onsite.

The vast majority of voltage sags come from the HVAC. If this facility is a industrial site other common issues come from elevators, escalators, compressors, welders, motors, pumps, etc.

Generally speaking, all network related hardware should be supplied & powered by dedicated circuits at the service panel.

Doing so avoids voltage sags / surges / spikes from a shared circuit like a photocopier, microwave, toaster etc. 🤦‍♂️

The first step is to review all the event / data logs on these units. Identify when this problem started and see if there is a pattern / frequency.

All of the NMS / Syslog servers should be reviewed for better long term insight as to the start, frequency, duration, and graphs to see the low / high metrics. 

Next, engage the facility to determine if any changes have been made to the electrical system or new equipment has been added / installed.

If the facility has a backup generator this is a logical area to consider and review if and when any monthly tests are conducted to ensure a (Lights Out / Grid Down) come on line as expected. 

Every serious facility will have some kind of power quality monitoring system in place. Review the logs / graphs to see if the entire building vs specific floors / rooms / circuits are impacted vs not. ☝️

Every IT Department will have a Fluke Power Quality Analyzer - Use it.

This will speed up the troubleshooting process and eliminate key areas. Armed with this information you have hard data which can be shared and used to help narrow down the root cause.

Ultimately, you may simply find there is dirty power coming into the building! Nothing for you to do unless the variance is above the industry standard for voltage swing, frequency drift, and THD.