PFC PSU dies when UPS kicks in - sine wave issue?

[lpvoid]

Hello all,

Has anyone had a problem with a PFC 450W PSU switching the computer off when the UPS switches to battery?

From what I can tell the UPS is only sending +, 0 and - out and not a proper sine wave. This is playing havoc with the PSU and the UPS then thinks its being overloaded somehow and switches itself off.

The PSU seems to work fine on battery when the load is lower (eg unplugged HDD's)

Any ideas? I think I probably need some form of power conditioning after the UPS. Cheap solutions anyone?

TIA.

 

[lpvoid]

*nudge* - anyone, please?

 

[Nerfherder]

I had the same issue when I plugged too many things in to the UPS. During games the PC would just restart. When i plugged it directly in to the wall it was fine.

You are pulling too much power

 

[sn3rd]

I would check the load and line regulation. Chances are that your load regulation is not good enough. => As Nerfherder said: "You are pulling too much"

 

[lpvoid]

Thanks for replying guys. I doubt its the load. I've pretty much got one machine (not monitors or anything) on a 800VA APC UPS

 

[Gnome]

What kind of PSU and are you sure you plugged the PSU into the socket that is connected to the battery, many UPS's have sockets that simply provide surge protection for higher load devices.

 

[The_Unbeliever]

What happens if you put a lighter load appliance (100w light bulb) on the UPS? How long does it run? Chances are your UPS's battery might be dead, and it cuts out when the power goes off.

 

[lpvoid]

Gnome: I'm sure I'm plugging it into the correct socket
trollwhore: The UPS works 100% with 4 other power supplies

An electronic engineer told me its because of the stepped sine wave approximation. The PSU need a line conditioner between it and the UPS once the battery kicks in. The thing is the step is +, 0 and -. Its pathetic. Anyone know where I can get a power conditioner?

 

[Gnome]

Once again what kind of PSU do you have and also what kind of UPS is it (exact unit names)?