Hardwired UPS device


I'm looking for clarification on a few parts of the Dell UPS hard wire installation requirements.  We have a Dell 3750W UPS (UK) and looking at the userguide it requires the following:

250V/30A, 2-pole circuit breaker (25A for 3750W/230V UPS models) to provide short circuit and overcurrent protection.

The protection device requires a two-pole disconnection device between the UPS output and the load.

The breaker must be wall-mounted and be readily accessible to the operator.

For Europe, the breaker must meet the IEC/EN 60934 standard and have a contact air gap of at.

We have an electrician who will be installing the device, but i would like to know (just in case he needs assistance) what the above requirements are.  From our main circuit in our warehouse we have an armoured cable which feeds into a fuse box in our data centre where the UPS will be installed – I take it that his is ok to run off this fuse box into the UPS device?

Is the 2-pole circuit breaker similar to an RCD in the fuse box?  What is the protection device – is this just an emergency trip switch located on a wall in the server room to disconnect the UPS power?

Really hope someone can give me a few pointers.

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Randy DownsConnect With a Mentor OWNERCommented:
I don't see the part you refer to but I would think your electrician would be fine with the required kit.

I haven't seen Europe installations but in the US the disconnect is just a big switch with a handle.

Dell 3750W 4U 230V Rack UPS High Efficiency Online Hardwire/Electrician Required - Kit
Manufacturer Part : 450-14148
Dell Part : 450-14148
Randy DownsOWNERCommented:
I would just go to Dell  support & start up a chat session.
anthonytrAuthor Commented:
I have, and they said that all they know is in the user guide...  They also said that APC manufacture the unit, but APC want speak to me as i didnt purchase the unit from them.  Really helpful Dell :)
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Randy DownsOWNERCommented:
I see. What's the APC part number. Maybe we can find your specs with it.
anthonytrAuthor Commented:
I'm afraid the device is at the office and i'm at home (still working).  All i can offer is the Dell link:


The bit which confuses me is the "protection device requires a two-pole disconnection device between the UPS output and the load".  When it says between the UPS output and the load, does that mean between the UPS and the servers etc?

Randy DownsOWNERCommented:
yes the servers would be the load and anything else plugged into the circuits powered by the UPS.
anthonytrAuthor Commented:
Finally got through to someone at Dell who confirmed that an RCD in our data centre fuse box is all that's really required.  So basically we would have a cable from our fuse box (RCD) to a fused socket on the wall and then to the UPS.  We could add an extra switch on the wall between the UPS and the Fuse box, but as its already connected to an RCD i dont see the reason.  No harm either way.  

The user guide for the device is here: http://support.dell.com/support/edocs/acc/upsd/en/ug/ol4200w.pdf

the bit i was refering to is on page 27.  

Just saw a section regarding installing a Remote Emergency Power Off option - sureley for such a small UPS i dont need this...do i?

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