Myth: UPS can't run on inverter?

[linuxtechie]

Folks,

I have a pure sine wave inverter. Hence the power quality is claimed to be better than the regular power supply (MSEB). So was wondering as why UPS can't be run off inverter? Is it a myth?

Mine UPS: Powersafe 600VA, Inverter: Sukam Pure Sine Wave 800.

~LT

[srijit]

I do run my UPS off an inverter, but that has got nothing to do with sine waves. The power supply for the UPS is included in the inverter wiring. So when the current goes, the inverter powers the UPS. When the inverter stops working, then the UPS (600VA) lasts for about 30 mins (laptop,TFT monitior) and then stops.
I do not know the effects of running an UPS through an inverter, but so far have had no problems.
ps: Inverter is a local brand. Dont know rating.

[directinjection]

It's the conventional non-sine wave inverters that create problems for UPS, not the pure sine wave ones, some of which even come with a built-in UPS feature, eliminating the need for UPS.

My conventional inverter damaged my UPS on the very first day of installation when power went off. Had to get UPS's PCB changed. Since then I've been using the UPS through the 15A power socket that doesn't get power from inverter. No problems since then.

[anujmishra]

Originally Posted by linuxtechie

I have a pure sine wave inverter. Hence the power quality is claimed to be better than the regular power supply (MSEB).

Who said the pure sine wave inverter is better than AC power supply by electricity board? LT, even if you are getting pure sine wave (as claimed by inverter manufacturer) it comes with spikes and some element of squares in it wave pattern. So, it is no way comparable to pure AC supply by MSEB or any other electricity board.

Secondly, most of the Sukam inverter comes with dual mode (UPS & inverter). There is switch in the back side for selecting the mode. I am also having Sukam Pure Sine Wave Inverter 800VA model. It has both the mode in it. As long as your inverter is in UPS mode it is safe to run computer in it directly no extra UPS required.

[directinjection]

Originally Posted by anujmishra

Secondly, most of the Sukam inverter comes with dual mode (UPS & inverter). There is switch in the back side for selecting the mode. I am also having Sukam Pure Sine Wave Inverter 800VA model. It has both the mode in it. As long as your inverter is in UPS mode it is safe to run computer in it directly no extra UPS required.

Any idea why the UPS mode is optional? What are the drawbacks of keeping the inverter in UPS mode all the time? Would the back-up be lesser?

[anuragn]

I also have Sukam 800VA Pure-Sinewave invertor. I also wonder what is the difference between the 2 modes. Does the UPS mode burden the machine with higher loads during switchovers? My dealer told me to always keep it on invertor mode.

[linuxtechie]

Originally Posted by anujmishra

Who said the pure sine wave inverter is better than AC power supply by electricity board? LT, even if you are getting pure sine wave (as claimed by inverter manufacturer) it comes with spikes and some element of squares in it wave pattern. So, it is no way comparable to pure AC supply by MSEB or any other electricity board.

Sukam did .

Originally Posted by anujmishra

Secondly, most of the Sukam inverter comes with dual mode (UPS & inverter). There is switch in the back side for selecting the mode. I am also having Sukam Pure Sine Wave Inverter 800VA model. It has both the mode in it. As long as your inverter is in UPS mode it is safe to run computer in it directly no extra UPS required.

Hmm, yeah, I as well have the same features, however I didn't use it as I already have the UPS with me. Just wanted to know if I can use them side by side.

~LT

[codemarauder]

My Microtek UPS is running since last 1 years on a Hyundai (non-sinewave) inverter. No problems as such.

[Sankar]

My UPS used to hum when it was run on Inverter during power cuts. My old laptop was used as a desktop replacement mostly as it's batteries were kaput. So if it was powered from Inverter (through the UPS) i used to get a small shock from the chrome parts of the laptop, which was touchpad surround and bezel surrounding the row of power and other buttons. There was no shock if the power was from the grid. This used to happen with my old Compaq Presario 1505 laptop.

[dkamath]

Hi all, want to share an experience, though not well versed with the technicalities behind the working of the home inverter as well as the UPS.

When we moved into another house, all lighting points were laid out so as to be fed with the inverter power. Once, the power went off, and so did the Wipro 'eMerge' UPS and the SMPS of my PC. Got the inverter supply removed from the PC power socket, since then.

[emkay456]

In addition to possible UPS damage on Inverter supply I have been informed that decorative LED displays (the ones that blink continously and generally used for deities / show cases etc) also get damaged. Had an experience of a dimmer rotary switch going kaput on Inverter supply, the switch being used for a ceiling fan regulation and relatively new.

[linuxtechie]

Originally Posted by dkamath

Hi all, want to share an experience, though not well versed with the technicalities behind the working of the home inverter as well as the UPS.

When we moved into another house, all lighting points were laid out so as to be fed with the inverter power. Once, the power went off, and so did the Wipro 'eMerge' UPS and the SMPS of my PC. Got the inverter supply removed from the PC power socket, since then.

Originally Posted by emkay456

In addition to possible UPS damage on Inverter supply I have been informed that decorative LED displays (the ones that blink continously and generally used for deities / show cases etc) also get damaged. Had an experience of a dimmer rotary switch going kaput on Inverter supply, the switch being used for a ceiling fan regulation and relatively new.

Hmm I am getting kind of mixed responses here. I guess I will try them together and observe them.

BTW, a question though: So Pure Sine Wave is not pure sine wave et all?

~LT

[anuragn]

@linuxtechie,
A so called pure-sinewave invertor actually produces a "simulated sinewave", which is an approximation of a sinewave. A real sinewave requires a physical device such as a rotor rotating in presence of a magnetic field, which is nothing but a dynamo (or generator). I am not saying that a pure sinewave cannot be produced electronically, but that there would be some distortion in the shape.

[linuxtechie]

Originally Posted by anuragn

@linuxtechie,
A so called pure-sinewave invertor actually produces a "simulated sinewave", which is an approximation of a sinewave. A real sinewave requires a physical device such as a rotor rotating in presence of a magnetic field, which is nothing but a dynamo (or generator). I am not saying that a pure sinewave cannot be produced electronically, but that there would be some distortion in the shape.

Ok, thanks, I see what you are talking about, appreciate it.

~LT

[mail4loys]

I have a different experience with Inverter and UPS. Whenever current goes off and main switched to inverter source, the inverter would trip (overload / safe mode)if my UPS is on. If it is switched of everthing comes to normal. due to this i have stopped using UPS and my computer runs on interver during power break without any issues!