Accidently switched off Symmetra LX Unit. Forced it into Bypass mode. How to take out?

[Anonymous user]

Soooooo, I accidentally bumped the "System Enable" switch and powered off our APC unit. Quickly switched it back on and waited but our equipment were not powering back on. Had to force into Bypass mode to get power back. Everything is working now - No errors popping up on the APC Unit. Right now it is at 100% charged with 5% load. Runtime has changed since but stay at 11 hours right now. Few questions:

- Why wasn't the unit still running off the batteries? All of them were charged?

- Are all the batteries bricked?

- Is it back running off the batteries?

- How do I take it off of bypass mode - or what procedures do I have to go through to get back on batteries and off bypass??

[BillP]

Hi William,

When you turned System Enable back on, just like on an initial power up, it puts the UPS into a mode called "load disconnect." From this mode, the user is supposed to go to the front LCD screen and command the load on after they've verified their input power is good, everything is wired properly, etc. It is designed this way to avoid problems with the power fed through to your load. 

Anyway, how did you put the UPS into bypass? By the physical maintenance bypass switch to the right of the LCD menu and behind the front bezel? If so, then you'd just quickly flop the switch back over to the left where the UPS will do a self test and bring the UPS back "online." If you switched the UPS into bypass some other way, let us know the details. You'd ultimately just take it out of bypass the same way.

Here is a explanation on the UPS and how it does charge the batteries while in bypass: http://www.apc.com/us/en/faqs/FA165403

Putting a UPS in bypass essentially means you bypass your UPS. The UPS consists of rectifiers, inverters, and the batteries. So ultimately, bypass causes the UPS not to run off of its batteries and that is why the unit is no longer operating "online."

Hope this helps. You just need to take the UPS back out of bypass the way you put it in and then you will see it come online and bypass LED/status go off.

[Anonymous user]

We did not put it in Maintenance Bypass. On the LCD screen we went to Control > Selected "UPS Bypass".

[BillP]

Hi Wlliam,

Okay, just go back to that same option in the PowerView LCD and you should see an option to take the UPS out of bypass now that the UPS is in bypass. Alternatively, if you use the on board network management card, you can log in to that and accomplish the same.

[Anonymous user]

So our worry is since we had to force it in Bypass to power the equipment on, going off Bypass will power it all off? Your saying that we turn off the bypass and it should automatically go back to running off the APC unit?

[BillP]

Hi William,

Yes, the power will remain on. The UPS will attempt to bring itself online by doing a UPS self test. For some reason, if the UPS failed the self test or there was another reason why the UPS could not bring itself back online to UPS power from bypass, it'd tell you it cannot come out of bypass but the load would stay on still. That message would be something like UPS in bypass due to fault.

There is logic built in that the UPS would make sure everything is okay before transferring the load out of bypass in order to avoid the situation you've described. "The UPS will consider the command and transfer the UPS into bypass if input line conditions are appropriate. The same is true when issuing the command to exit bypass -- the UPS must be safely able to transition on-line or else the UPS will remain in bypass." - found that in some documentation to further explain.

Unless you have a fault message or alarm showing on the LCD, there would typically not be any reason to worry. If you feel more comfortable walking through this with someone on the phone too, we can do that @ 1-800-890-4272.

Here are also some other pieces of reading material we have on bypass for the single phase units, like Symmetra LX.

• http://www.apc.com/us/en/faqs/FA157500 - Bypass settings of Single Phase Symmetra UPS systems
• http://www.apc.com/us/en/faqs/FA157509 - why the UPS would turn off the load when coming out of bypass

Hope that helps!

P.S. - the reason why the load off went originally is because you touched the master power switch for the whole frame - System Enable. The reason it did not come back on when turning that switch back on is because of what I mentioned originally - the UPS electronics get energized but the UPS is in load disconnect mode until the user goes to the LCD and commands the load on. Bypass ultimately forces the load on - maintenance bypass switch or the command option you did. All of this is normal and by design.

[Anonymous user]

Angela, you are a Christmas miracle! I can't thank you enough. We'll be performing this off hours but i'll be sure to let you know how it goes.

[BillP · Accepted solution]

You're welcome  

Based on what you've said, I think there is an extremely slim chance something will happen but to ease your concerns, we do offer after hours Symmetra support here in North America. That way, if something happens slightly differently than I described or you have questions right there in the minute, you can take advantage of an expert by calling the main number I mentioned. Then, they transfer you to someone for help. I am not sure what your "after hours" is but the call center is open 8a-8p ET and after hours is around that time frame.

Hope you have a nice holiday and everything goes smoothly