RT-AX55 not running on UPS anymore

[drinkingbird]

So, the problem was in the power adapter. I had an old AC-1200 lying around. I connected the router with it’s adapter and router is now switching on UPS without any problem.

I'm assuming you're using a simulated sine wave UPS? Those will degrade power supplies if you have a lot of "on battery" events. Some power supplies (such as the high efficiency ones in many modern PCs) won't even run off those UPSes. Probably cheaper to just get a new adapter every couple of years than replace the UPS, however it could also be damaging the router itself over time.

 

[Kashif Tasneem]

Y

I'm assuming you're using a simulated sine wave UPS? Those will degrade power supplies if you have a lot of "on battery" events. Some power supplies (such as the high efficiency ones in many modern PCs) won't even run off those UPSes. Probably cheaper to just get a new adapter every couple of years than replace the UPS, however it could also be damaging the router itself over time.

Yes, it's a simulated sine wave UPS.

 

[drinkingbird]

Most likely the reason why the power supply failed. More heat is generated when plugged in square wave UPS.



My experience is different. I mostly use APC UPS and the batteries last about 3 years. I change them on schedule every 2 years.

Well a square wave UPS would probably fry it in a few minutes, I'm assuming you mean stepped sine wave (yeah I'm being nit picky). Some really junk UPSes a long time ago used triangle waves, sometimes with a filter to flatten the top and bottom. Those were awful. I know I've read in theory that square wave UPS did or do exist, but I've never seen one, and can't imagine the havoc it would wreak.

I always use CSB batteries, they give me 5 to 7 years before hitting below 50% runtime, but I also don't have many outages, and very rarely a full discharge (full discharge kills the batteries). I also installed a potentiometer in my UPS so I can adjust the float voltage to be dead center of the range the batteries want. Too low and your runtime is reduced but not terrible for the batteries, but even 10% too high will cut their lifespan significantly. From what I've seen, UPSes do not have very good float voltage calibration, and even if they do at first, over time it changes.

I've now switched to the new CSB LL (Long Life) which are designed to supposedly last 8-10 years as long as you don't deep discharge them too often. We'll see, they weren't much more expensive.

 

[drinkingbird]

Y


Yes, it's a simulated sine wave UPS.

Yeah, in reality, it isn't that surprising. These tiny wall wart power supplies these days are not very robust, and even if they were, eventually that simulated wave will degrade components. Some simulated waves are better than others, I've seen some cheap UPSes that only have a few steps, like a small pyramid, while others have dozens of steps. But regardless, it is harsh on electronics.

If you have frequent on-battery events, like even 3-4 a year, especially if they are for more than a couple minutes, may be worth investing in a true sine wave UPS next time you need batteries, or even sooner. Just think of what other things you have plugged in and the damage it may be doing to those.

 

[L&LD]

Why would that have anything to do with it? The firmware and settings aren't going to make it magically draw power out of thin air.

When I posted, the power adaptor wasn't the known culprit. Basic troubleshooting steps, firmware, and settings won't draw power out of thin air but have been known to cause router instability.

 

[drinkingbird]

When I posted, the power adaptor wasn't the known culprit. Basic troubleshooting steps, firmware, and settings won't draw power out of thin air but have been known to cause router instability.

Firmware and settings will not stop a router from powering off only when the UPS switches to battery. No way, no how. If this was a high end device that had communication with the UPS and knew its status then sure, it could be settings related, but this is not that. Or maybe if you could somehow enable enough features so that you exceed the UPS's rating that would cause it, but again, not gonna be the case here.

If it was randomly rebooting regardless of UPS sure, your suggestion is perfectly valid. But only happening exactly when the UPS switches to battery, nah.

 

[L&LD]

Your opinion.

Unless you test for it, you don't know.

And, I did guess the power adaptor too.

 

[drinkingbird]

Your opinion.

Unless you test for it, you don't know.

And, I did guess the power adaptor too.

Opinion, science, common sense, logic, whatever you want to call it.

At the very least a hardware fault is far far more likely so before putting someone through the time consuming effort of factory reset, would make sense to rule out other hardware stuff first. Kinda like calling your cable company and you tell them their router caught fire and melted and they ask if you tried rebooting it.

 

[L&LD]

No, not kinda like that at all, is it? Common sense isn't so common, it seems.

As I said, it has shown up before, time consuming? Not so much. (Take a backup, restore if issues don't clear up), time to test, less than 10 minutes, tops.

 

[drinkingbird]

As I said, it has shown up before,

Link to an example where UPS switching to battery caused router to reboot and it was fixed by firmware upgrade/factory reset?

As far as the cable company comparison, your default response seems to always be factory reset and firmware upgrade, their default response is always reboot the modem. Seems like a reasonable analogy to me.

 

[L&LD]

Never said I saw such an example. I think outside the box, and 10 minutes (max) to test for something is reasonable and that is within reach of anyone on these forums. You, however, conveniently ignore that direct answer to your multiple incorrect assumptions.

My default response is to tailor my answer to the user I'm trying to help (and/or further clarify the thread topic where I can).

If a factory reset is all you (ever) read, it isn't a problem on my end. The users I help seem to appreciate the input I give.

 

[Tech9]

Well a square wave UPS would probably fry it in a few minutes, I'm assuming you mean stepped sine wave

No. APC Back-UPS BE425M model is a popular entry-level square wave UPS. Most electronics work well with it, just power converters generate more heat, sometimes more noise. Not ideal, but works well enough for the price. It's a standby type UPS and in normal operation the load is directly powered.

 

[drinkingbird]

Never said I saw such an example.

You said "As I said, it has shown up before". Whatever, I give up.

 

[drinkingbird]

No. APC Back-UPS BE425M model is a popular entry-level square wave UPS. Most electronics work well with it, just power converters generate more heat, sometimes more noise. Not ideal, but works well enough for the price. It's a standby type UPS and in normal operation the load is directly powered.

Hopefully it at least has 2 steps to the square wave (smaller square on top of larger square), I've seen that before. Basically simulated sine wave but with only 2 steps. But definitely worth paying more to at least get a good simulated sine wave, these low end junkers are going to destroy equipment. After hearing buzzing from my power supplies on a simulated, I went to true sine and will only use that.

They're all standby/line interactive, only real high end ones are "online", would be nice to have but too much $ and they are less efficient also.

 

[ColinTaylor]

Hopefully it at least has 2 steps to the square wave (smaller square on top of larger square), I've seen that before. Basically simulated sine wave but with only 2 steps. But definitely worth paying more to at least get a good simulated sine wave, these low end junkers are going to destroy equipment. After hearing buzzing from my power supplies on a simulated, I went to true sine and will only use that.

It's 15 years old now (and on a HTTP website) but there are some interesting traces of APC output here: http://www.jkovach.net/projects/powerquality/

Maybe APC are using more "steps" in their entry level UPS's, but I doubt it. They say it's "ideal" for computer and network equipment but to my mind that's a pretty ugly looking signal. If it were feeding a traditional linear power supply I wouldn't be concerned, but as almost everything is switched mode nowadays I'm not so sure. Even if it doesn't cause any damage I can image that there could be enough of a glitch at switchover to cause the problem the OP was experiencing. (But the OP never stated what UPS he was using so this is just speculation)

 

[Tech9]

But definitely worth paying more to at least get a good simulated sine wave

It all depends how critical the equipment is and how often the power goes out. Consumer routers are fine with BE425M type UPS.

 

[drinkingbird]

It's 15 years old now (and on a HTTP website) but there are some interesting traces of APC output here: http://www.jkovach.net/projects/powerquality/

Maybe APC are using more "steps" in their entry level UPS's, but I doubt it. They say it's "ideal" for computer and network equipment but to my mind that's a pretty ugly looking signal. If it were feeding a traditional linear power supply I wouldn't be concerned, but as almost everything is switched mode nowadays I'm not so sure. Even if it doesn't cause any damage I can image that there could be enough of a glitch at switchover to cause the problem the OP was experiencing. (But the OP never stated what UPS he was using so this is just speculation)

Yeah those are the 2 step square waves (predecessor to the simulated sine wave of today) of the old cheap ones. Too bad they're still using that in the low end boxes. I would never trust one.

 

[drinkingbird]

It all depends how critical the equipment is and how often the power goes out. Consumer routers are fine with BE425M type UPS.

Well, would appear from this thread they aren't necessarily.... I guess if you have one short outage a year and generally power quality is good (AVR doesn't kick in) then probably ok.

I've seen many devices damaged by these low end UPSes, can't prove it in every case but usually it is after a power outage or a person who has frequent switches to battery. Luckily, usually the power supply is the "sacrificial lamb" and you just need to replace the power supply, have seen it in PCs mostly but also a phone charger, and a few "wall wart" driven devices like these routers.