APC Silcon SL60KH ECO mode using more power than normal

[jddixon_apc]

Hi Everyone

We have a APC Silcon SL60KH that seams to pull 3-4x MORE power when eco-mode is active than when normal operation is selected. In Eco-mode the inverter is off and it pulls around 18amps per phase. When in normal mode the inverter is on and it pulls 3-4amps per phase (the room also gets pretty warm. Has anyone else witnessed this behaviour and any idea what could be the problem? The data floor it is serving is empty at the moment (no load) but when we attached a 1200w load the same range of readouts were observed. Also when eco-mode is active the menu on the front of the unit indicates it is pulling 1 amp per phase when the facility meter indicates substantially more.

The UPS itself is quite old and is of 3phase 415v design. It had a new PSU board not so long ago as some of the small capacitors were swollen. 

Any advice would be grateful.

Thanks

Jon Dixon

[BillP]

Hi,

While in ECO mode the UPS would be running on the Static Switch - essentially connecting the loads directly to the input. You would never expect to see more current in ECO mode then when in normal. While in ECO mode there is no input power factor correction, but as you mentioned there is no load here at all, so nothing that would be going back to utility anyway. And it is also interesting that you mention the display shows little to no current, but it is definitely pulling it as you have metered it.

So having said all that, our suspicions would be something is wrong with the static switch, or the control issues to the static switch. This is definitely a good one to call into the local tech support group for your country.

Link to local support contact page http://www.apc.com/site/support/index.cfm/contact-information/

[jddixon_apc · Accepted solution]

Hi Bill

Thanks for replying. We decided to retire the unit in the end and replace it with 2 more modern Smart UPS VT units.