[SOLVED] Cold-start capable UPS?

cteno

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Apologies if this should be in a different forum, e.g. "power supplies."

I have owned quite a few backup power supplies. Just picked up a CyberPower LX1500GU for a special purpose: leaving plugged in to maintain charge, but with no load. Then I can put it where needed during a power outage, when another UPS runs out of battery charge or some small appliance needs juice.

Turns out that this doesn't work. I called Cyberpower, and the tech explained that this model has a "cold start lockout." I pointed out that this limits utility, even if for just a fraction of buyers.

As an experiment, I tried powering the UPS with a small 18650 battery inverter. The Cyberpower unit turned on, and stayed lit even after disconnecting the inverter. So that's a kludge workaround.

I'm trying to decide whether to return the unit and get another, or just live with it. I know that some UPS models can be cold-started, but manufacturers don't seem to advertise this feature/lack. Can anyone point to a master list of cold-startable backup power supplies?

Thanks!
 

Ralston18

Titan
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Correct: manufacturer's are not compelled to list some lack of function and they are likewise very good at not making such short-comings easy to discover.

And I do understand the idea of having UPS just sitting somewhere with a fully charged battery and ready to power some device for at least sometime.

Much like those portable USB phone/laptop chargers that are basically just a charged battery to serve as a power source.

That said, the lamp idea was a suggestion that may serve as a "work around" to the lack of a cold start capability.

All the UPS knows is that there is some load (maybe a night light) being supported. So the UPS sits there, plugged in, powering the nightlight.

Power goes off, load stays powered, and you (hopefully) can add another device or two to the UPS's battery powered sockets.

However, I understand that you need to move the UPS to another location where it is needed in an emergency.

So leave the nightlight plugged in and on, move the UPS, plug in what needs to be powered.

May worth some testing.
 
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Ralston18

Titan
Moderator
Interesting:

Can you maintain the Cyberpower's UPS function per se by just plugging in a 40 watt lamp?

Or even a night light.....

Lamp would continue to be powered if main power was lost and then you could plug in a PC as another load.

Then turn off the lamp....

Just a "thought experiment".

The UPS certainly cannot know what load or loads is/are being supported.

Experiment some.
 
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cteno

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I may not have expressed myself clearly. Issue is not with load, but with cold start: the ability to have the UPS fully charged but not plugged in, and turn it on (with or without load) when there is no power on its input side. That way, it can be kept charged, then moved to wherever needed in emergency. This CyberPower model does not do that, though others apparently do. (There's even a cold start section in the CyberPower FAQ.)

I guess that so few people want to do this that the manufacturer's don't feel compelled to list the ability (or lack thereof) as a significant system specification.
 

Ralston18

Titan
Moderator
Correct: manufacturer's are not compelled to list some lack of function and they are likewise very good at not making such short-comings easy to discover.

And I do understand the idea of having UPS just sitting somewhere with a fully charged battery and ready to power some device for at least sometime.

Much like those portable USB phone/laptop chargers that are basically just a charged battery to serve as a power source.

That said, the lamp idea was a suggestion that may serve as a "work around" to the lack of a cold start capability.

All the UPS knows is that there is some load (maybe a night light) being supported. So the UPS sits there, plugged in, powering the nightlight.

Power goes off, load stays powered, and you (hopefully) can add another device or two to the UPS's battery powered sockets.

However, I understand that you need to move the UPS to another location where it is needed in an emergency.

So leave the nightlight plugged in and on, move the UPS, plug in what needs to be powered.

May worth some testing.
 
Reactions: cteno

cteno

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Aha - my apologies; I did misunderstand the depth of your reply. If a very small load can keep a UPS running, then it would allow the unit to stay on while moving from a dead wall circuit to a needed location.

So - just did the experiment, with an LED night light. It's working just fine, and the UPS display says that battery duration will be 15 hours. Night light uses something like 1/4W; I'm guessing that the larger (but still minimal) battery drain is DC-AC conversion overhead. And having a pilot light to find the UPS in the dark seems like a good idea.

This was very helpful to me, and I hope it will be to many others. If I can add tags, flags or anything else that will make Ralston18's advice more easily searchable, please tell me how.

Thanks again!
 
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