Lock Off Device for Triple Pole Main switch & MCB

TonyTheTiger · Apr 4, 2019

Hi all.
I am undertaking an assessment next week called SAFE ISOLATION OF SUPPLIES.

It involves isolating and securely locking off a circuit to be worked on. The 4 items to be isolated is THE WHOLE INSTALLATION, A 3 PHASE CIRCUIT, SINGLE PHASE CIRCUIT & LOCAL ISOLATION (which is an isolator switch for a commando socket.)

I know the little brass lock off is for single phase mcbs & my padlock can be used for the isolator switch for local isolation. However could anyone help me by showing me what device is used to isolate the whole 3 phase installation and if different what device is used to isolate the 3 phase MCB.

Candidate Guidance « Scottish Joint Industry Board – FICA - http://fica.org.uk/candidate-guidance/

Details for the assessment are in the link above under SAFE ISOLATION OF SUPPLIES

Thanks in advance

Tony

Deleted member 26818 · Apr 4, 2019

You can purchase a device, that looks like a small ‘G’ clamp.
You affix it to the toggle switch using an Allen key or knurled knob, then place your padlock in the hole to prevent anyone from undoing the Allen key or knob.
MCB Lock OFF device SAFETY maintenance electrician (*FREE PADLOCK) | eBay - https://www.ebay.co.uk/itm/MCB-Lock-OFF-device-SAFETY-maintenance-electrician-FREE-PADLOCK-/382859139540

buzzlightyear · Apr 4, 2019

Deleted member 26818 · Apr 4, 2019

buzzlightyear said:

Not sure that voltage indicator complies with GS38.
No finger guard on the red probe.

Andy78 · Apr 4, 2019

If this is an assessment, should not the appropriate equipment be provided for you ?

Chris1234 · Apr 4, 2019

A three phase MCB is three single phase MCB’s linked together (sort of) so you should be able to use the brass thing on the three phase if it fits on the single phase.

Deleted member 26818 · Apr 4, 2019

Chris1234 said:
A three phase MCB is three single phase MCB’s linked together (sort of) so you should be able to use the brass thing on the three phase if it fits on the single phase.

In many instances, you can use one of those spring clip things that go through the holes in an MCB.

TonyTheTiger · Apr 5, 2019

Apologies for the late reply. During the Assesment you are provided with various lock off devices by the assesorr. You have to select the correct device for each circuit you are locking off. That's why I know the brass device locks off single phase MCBs and the padlock will be able to lock of the isolator switch for the local isolation. I'm just not sure regarding 3 phase switchgear as I have never worked on 3 phase installations. That's why I'm looking for clarification regarding the 3 phase triple pole main switch and the 3 phase triple pole MCB.

Is the ideal lock off device for 3 phase switchgear the device with the little prongs that stick out at each side?

Deleted member 26818 · Apr 5, 2019

TonyTheTiger said:
Is the ideal lock off device for 3 phase switchgear the device with the little prongs that stick out at each side?

I believe the device with the little prongs will work on a 3phase MCB, as 3phase MCBs are effectively 3 single phase MCBs stuck together.

TonyTheTiger · Apr 5, 2019

Is this type of lock off device suitable for securely locking off a 3 phase MCB and 3 phase Main switch? As that is one of the itemsitems pro by the assessor.

[ElectriciansForums.net] Lock Off Device for Triple Pole Main switch & MCB

TonyTheTiger · Apr 5, 2019

spinlondon said:
I believe the device with the little prongs will work on a 3phase MCB, as 3phase MCBs are effectively 3 single phase MCBs stuck together.

Thanks mate. That's one of the lock off items provided aswel as a brass device (which is ideal for single phase MCBs). If the pronged lock off device is suitable for 3 phase MCBs would it also securely lock off a 3 phase Main switch aswel?

Deleted member 26818 · Apr 5, 2019

TonyTheTiger said:
Is this type of lock off device suitable for securely locking off a 3 phase MCB and 3 phase Main switch? As that is one of the itemsitems pro by the assessor.

View attachment 48667

I would say yes for a 3phase MCB.
I cannot for definite say yes for 3phase Main switch, without first seeing the Main switch.
If the Main switch is a 3phase MCB , yes it will work.
If the 3phase Main switch is a handle that you have to turn, no it won’t work.

TonyTheTiger · Apr 5, 2019

This is the main switch. So am I right in assuming the pronged lock off device will securely lock of this main switch and the 3 phase MCB?

I'm sincerely grateful for all the feedback provided by both yourself and others. I appreciate it greatly.

Michael Sands · Apr 5, 2019

Don’t forget the wee brass thing still needs a padlock and sigh fitted to it

Deleted member 26818 · Apr 5, 2019

TonyTheTiger said:
This is the main switch. So am I right in assuming the pronged lock off device will securely lock of this main switch and the 3 phase MCB?

I'm sincerely grateful for all the feedback provided by both yourself and others. I appreciate it greatly.

View attachment 48671

Yes, either the 2 prong thing, or the brass thing will work with that Main switch.