Dave mcn said:

They have confirmed that they just want it for manually switching over to mains supply if the UPS fails.

Isn't the idea that UPS takes over when mains fails?

Hi Chris

They've been told that they need a maintenance bypass switch for when the UPS fails or needs to be replaced.

There's currently nothing, and no way of maintaining the UPS without complete loss of power.

Hi Chris

They've been told that they need a maintenance bypass switch for when the UPS fails or needs to be replaced.

There's currently nothing, and no way of maintaining the UPS without complete loss of power.

UPS ..to a sprinkler pump via a control panel....

The circuit isn't critical ...

A description that sounds slightly unusual.  It may be worth checking what happens insurance and liability wise if there is a fire while the sprinkler system is off-line, and how critical the person in charge of the fire risk assesments thinks the UPS is - it  is not there for fun after all.

I suggest that it should not be too easy to leave the switch in the UPS bypassed state   - at the least least a warning light or similar would be good.

I presume it is all single phase and less than 32A from the switch you are looking at.  Electrically your plan makes sense, but be really careful you  don't accidentally introduce a weak link where an unfortunate misunderstanding about switch positions could mean the building is left without sprinklers for any length of time and no one realises.

I'm not sure that 3 position, centre off is a good idea in this case.

Mike.

If the UPS needs to be turned off to change batteries or whatever, then if it can't its installation is a bit sub-par already

Hi Mike

Tank you for the reply

I have the exact same concerns and i emailed them so they could clarify what the requirements are.

The installation is very sub-par, and has been like this for many years i believe.

I have ordered this https://www.ebay.co.uk/itm/324235583344

If it doesn't comply then I'll send it back, but they have confirmed it is for the removal of the UPS if they ever need to do so.

With this Salzer bypass switch and the existing 2 rotary isolators for the UPS they will be able to achieve this and keep power on to the sprinkler pump.