Device on UPS reboots after mains switch over

Dieselboy · January 13, 2019, 09:02:09 PM

I have a device in the remote office which is owned by our telco. It's a wireless radio. When our remote office has a power outage (which happens often), we lose internet for a brief moment because for some reason the wireless radio which runs the link to the ISP drops. This device is powered by a UPS but I think during the switch over, the mains feed to the device must be out of range and the device either crashes or just loses power for a split moment which is enough to cause it to go off.

All other devices on both of our UPS's are fine and continue running. We have moved this device between both of our ups and it drops offline during power outage for both of them. There's no issue any other time when the mains feed is normal. When the ups is running on batteries = no issue, it's just at the point where the mains switches over to batteries and back again. The issue also happens at the self-test time. Again, only that device drops. None of our server or Cisco equipment is affected.

I can't say I think it's faulty. It's difficult for me to ask them to replace it and give a proper reason... "Sir why do you think it's faulty" me: "Well because when there is a power outage, the device turns off" them: "lol".

My plan was to ask for the input power requirements such as frequency and voltage then to see if the UPS is reporting output power outside of the boundaries there. I've yet to have that info.

Thought I'd post here to see if you guys had any suggestions?

deanwebb · January 14, 2019, 02:57:33 PM

Is there a battery in the device itself? If so, it may need replacing to deal with the overall power issues.

Dieselboy · January 14, 2019, 11:48:38 PM

I'm not sure.. There might be a bios battery but I doubt it would keep the system running.

The device is a Ubiquiti wireless antenna. The ISP also brought in their own UPS and was powering the unit from that but it still dies during the mains power cut.
Power in Sri Lanka is 230v 50Hz which is the same as here in Oz although at the moment the Australia UPS shows 247v input and Sri Lanka shows 231v input.

I have just tried to find out the mains requirements of the ubiquiti.. I was thinking may be the power adaptor on the device is expecting 60hz and during the power outage it deviates enough for the device to lose power.
While checking the ubiquiti manuals it shows that they have a PoE injector from the mains to the antenna where ours is on the roof, so another theory that I have is that the cable might be too long or have a quality issue.

icecream-guy · January 15, 2019, 06:44:34 AM

I'll bet the Ubiquiti wireless antenna is not plugged into the UPS. sounds stupid, but I've seen stuff like this. go verify yourself, or get pictures if possible.

Dieselboy · January 15, 2019, 09:14:31 PM

That's what I was saying from the beginning.... You might be right, but they assure me that it is plugged in to the ups. I'll follow up today as they are back from leave. Sri Lanka have so many public holidays including one every full moon

SimonV · January 16, 2019, 04:47:44 AM

Maybe there's a passthrough port on the UPS

deanwebb · January 16, 2019, 07:48:31 AM

Quote from: SimonV on January 16, 2019, 04:47:44 AM
Maybe there's a passthrough port on the UPS

A UPS with bypass mode?

* deanwebb does a Google search on "ups bypass mode"

Huh. It's actually a thing.

BRB, posting on the TIL thread...

icecream-guy · January 16, 2019, 11:13:31 AM

Quote from: deanwebb on Today at 08:49:00 AM

TIL that there's such a thing as bypass mode for UPS devices.

--
yeah, the UPS will have like 6 plug ins for connections, and only two of them are for UPS, the others are surge suppression only.

mmcgurty · January 17, 2019, 08:29:25 AM

You might need something that does line conditioning as well as provides UPS functions. The industry has a lot of names for it. Buck and Boost and AVR are the two that come to mind. We had Transition Networks transceivers in a steel manufacturing site with lots of large motors and such. We had one area that was near these motors and they had a UPS for these transceivers but we would still lose the link. We found out the UPS that was in place didn't provide voltage at like 100-109V that the line would drop down to when the motors would kick on. At 110V and up it would work fine. In that case, the plant electricians installed a Sola (brand?) line conditioner for that area of the plant and it cause our problems to go away.

As we moved forward, we started purchasing APC UPS'es with voltage regulation and you could tell it if the voltage drops to that 100-109V go on UPS and provide power until the line returns to a normal threshold. I would definitely look into your equipment specs, but it sounds exactly like what I have dealt with in the past.

Dieselboy · January 21, 2019, 04:37:47 AM

Yes I know what you mean. We dont have that, I checked

Actually we have tried three different UPS now. A managed APC which is our primary. A non-managed 2nd one and the ISP brought in their own one.

The ISP says that there is simply too many things plugged in to the ring main.

I already know that the mains wiring is dodgy in certain locations of our office. Sometimes you can plug a laptop in, the socket arcs and a few monitors switch off on the desks next to you. But this is a desk island. As far as I know, the mains fom the wall sockets are fine, but I've asked to get them checked.

mmcgurty - thanks for that I'll check. The mains power is dodgy there anyway. The power will just drop randomly throughout the day. I have seen alerts from our UPS with a message basically saying that there is mains power, but it's too dodgy so the ups is switching to battery. I'll find out if we have a conditioner in the ups and see if it needs tweaking and go from there.

My other thought is that the power cable (PoE) that they have is not per spec. Either too long or cat5 or something like that, and it's dropping voltage.

Thanks for the tips, all. I'm glad I asked