Hello
The Cyberpower 100 watts UPS with battery backup in the case.
Question is: disconnect ac power to the ups and let battery in case to take over power the computer work,now try connect power inverter 400 watts inverter using 100 ampere hour battery , don't work try use the inverter power to power the UPS.
Why not work like to know why not work.
El

 

UPS looks for a proper sine wave to determine if the power is "good". Most inverters have a modified square wave, and such a voltage pattern is not accepted by most UPS devices, as the power is not "clean", and would require the UPS to run. But without a good AC signal to start with, not likely it will start in the first place.

 

Hello
The Cyberpower 100 watts UPS with battery backup in the case.
Question is: disconnect ac power to the ups and let battery in case to take over power the computer work,now try connect power inverter 400 watts inverter using 100 ampere hour battery , don't work try use the inverter power to power the UPS.
Why not work like to know why not work.
El

If i understand you right, you are trying to use one UPS system to power another UPS system.
I am not sure why you would want to do that, but i would bet that the manual for either UPS system specifies not to use unusual things with the UPS system, even the use of a power surge protector may be discouraged. Check the manual for both UPS systems and see what they have to say.
Remember some and really a lot of UPS systems do not put out a clean sine wave they put out a set of pulses that very roughly mimic the average of a real sine wave. The response of another UPS to this kind of input may be not so good.

There are other issues too like start up current but you'd have to do some measurements to find out if something else is happening also.

 

UPS looks for a proper sine wave to determine if the power is "good". Most inverters have a modified square wave, and such a voltage pattern is not accepted by most UPS devices, as the power is not "clean", and would require the UPS to run. But without a good AC signal to start with, not likely it will start in the first place.

Sagor
Amazon sell pure sine wave inverter would pure sine wave inverter on the Ups?
Pure sine wave inverter are Not cheap.
El

 

If i understand you right, you are trying to use one UPS system to power another UPS system.
I am not sure why you would want to do that, but i would bet that the manual for either UPS system specifies not to use unusual things with the UPS system, even the use of a power surge protector may be discouraged. Check the manual for both UPS systems and see what they have to say.
Remember some and really a lot of UPS systems do not put out a clean sine wave they put out a set of pulses that very roughly mimic the average of a real sine wave. The response of another UPS to this kind of input may be not so good.

There are other issues too like start up current but you'd have to do some measurements to find out if something else is happening also.

MrAl
In Ups there is 12 volts battery at about 7 ampere Hour that would power television about hour and half.
So if put 400 watts inverter and 100 ampere hour battery should charge the Ups while Ups is powering the television.
Once the electric company restore power than connector to regular power.
Good thing about Ups power,power don't get lost circuit switch to battery AC.
What do you think of using a pure sine wave inverter would that work ,pure sine wave inverter are not cheap.
El

 

I don't think I understand this thread very well so forgive me if I have it wrong... you hope that you could power an UPS with another UPS that is plugged into the first UPS? That would create a "loop" of UPS feeding each other and power your devices longer (maybe indefinitely)?

If so that defies the laws of physics. You are better off just taking the battery from the smaller UPS and add it to the battery of the larger one.

 

The real solution is to find a UPS that will run off your external 100Ah battery. Some UPS are designed for add-on external battery banks.

 

MrAl
In Ups there is 12 volts battery at about 7 ampere Hour that would power television about hour and half.
So if put 400 watts inverter and 100 ampere hour battery should charge the Ups while Ups is powering the television.
Once the electric company restore power than connector to regular power.
Good thing about Ups power,power don't get lost circuit switch to battery AC.
What do you think of using a pure sine wave inverter would that work ,pure sine wave inverter are not cheap.
El

Hi again,

Oh in that case there could very well be am impedance that is too high between the big battery and the UPS. That would sink the voltage to the UPS and it would not run.
However, there could be a built in battery test that tests the battery to make sure it is the right type and maybe size too.

What i would do is check the wires connecting the big battery to the UPS and make sure they are heavy enough to handle the current and the connections are good and tight and also do not get hot after some time running. A bad crimp will cause high impedance and also extreme heating of the connector.
That's the first thing to do.
You could probably load the battery with a decent size load at the UPS DC input to test the voltage drop battery to UPS.

BTW sine wave output UPS systems have come down in price, maybe check again on the web.