Replacing dual UPS maintenance bypass switch.

[ekuegler]

Hi all,

Looking into feasibility of replacing a dual UPS (Chloride) maintenance bypass switch. Switch configured so that it has both UPS's terminating into it, live at all times via one UPS or the other. It is a F&G UPS, plant will be shutdown on isolation of power to catastrophic level. Is there any means around this, or anyone with similar experiences....? Trying to prevent going to catastrophic shutdown level.

Isolation will trip all plant and action an electrical isolation opening all battery isolators after a 20 min duration. No UPS or battery backed systems available at this point.

Looking into hooking a temporary UPS to power the distribution.

any suggestions welcome, alternate ideas welcome

EK

 

[sibeen]

ekuegler, a simple single line drawing may give us all a better idea of what you're trying to achieve.

Also, what is a F&G UPS, I've mucked around in the UPS industry for about 25 years and never heard the term.

Why do you need to replace the maintenance bypass switch?

 

[dpc]

Best approach is to have separate bypass switches and isolating switches for each UPS. With a dual maintenance switch, there is always a risk of common mode failure, assuming I understand the topography of the switch.

 

[ekuegler]

Sibeen, unfortunately I have no single line to hand - when I return to work I shall post. F&G is fire and gas. So as you can imagine this is were it gets tricky as removing all power sources in order to replace bypass switch leads to a catastrophic level shutdown having referenced the cause/effects matrix.

Need to replace switch as it is defective/seized in place and we are unable to complete any routine maintenance on the units.