Vir cabling allowed for fuseboard change ??

[MJPD29]

Thankyou for the advice and will take that on board moving forward. There is currently an rcd main switch which trips within required times, so no issue there. The circuits are doubled up and I need to re run a 6mm for cooker so upgrading the board was the best option. It's just this vir in a socket that concerns me, as by changing the board, you re signing off the install

But what are your IR results on this VIR cable? That’s really the main issue, you can’t sign anything off unless you have done your testing.

 

[freddo]

But what are your IR results on this VIR cable? That’s really the main issue, you can’t sign anything off unless you have done your testing.

The problem with rubber is it is an awesome electrical insulator, even when it has gone gooey or super dry and crumbly.

 

[davesparks]

Don't put all your faith in an IR test. You need to thoroughly inspect the cable and it's terminations before deciding whether or not to proceed with this.

That cable has well exceeded it's service life and you should really be looking at options to replace it.

As it is VIR it will be using the steel conduit as the CPC so you also need to thoroughly inspect and test that.

 

[nicebutdim]

Don't put all your faith in an IR test. You need to thoroughly inspect the cable and it's terminations before deciding whether or not to proceed with this.

I'd contend that any visual inspection would need to cover 100% of the cable.

I've seen rubber cable that has been perfectly supple and in excellent condition along the majority of its length, but with very small sections crumbling. In the OP's shoes I'd be absolutely certain about where I stood, before signing this off.

 

[Rockingit]

There’s also a commercial aspect to this too - assuming that it visually looks OK and you get an IR above 2Mohms, technically you’re OK to proceed however the client is going to be less than impressed when it fails in a years time and Sparky No.2 is giving you a right bashing for not having changed it ‘when it made sense’. I’d talk to the client and explain the overall situation and best practice would be to replace it regardless of if it still works today or not.

 

[7029 dave]

VIR is well over its service life, and IMO the priority is to get that replaced first.

 

[MJPD29]

It really should be replaced. Connecting it is taking a risk as you won’t be able to visually inspect 100% of the cable in most cases. Personally I would not reconnect and if client was objecting I’d prefer to walk away.

 

[davesparks]

I'd contend that any visual inspection would need to cover 100% of the cable.

That's impossible with VIR as its in conduit, and if it isn't in conduit then that a whole other problem as it is single insulated cable.

Obviously if it was an insulated and sheathed rubber cable like TRS or CTS then that may be possible to do 100% inspection.

 

[nicebutdim]

That's impossible with VIR as its in conduit, and if it isn't in conduit then that a whole other problem as it is single insulated cable.

Obviously if it was an insulated and sheathed rubber cable like TRS or CTS then that may be possible to do 100% inspection.

You raise a valid point, but I'd worked on the assumption that VIR is being used as a general term for rubber cable as other posts in this thread have done.

Somewhere in the installation the rubber cables have been joined to T&E and these joints haven't been found, much less inspected.

Given the age and type of cable under discussion, along with 'known unknowns', I don't think anything should be assumed about condition.

 

[brianmoooore]

VIR stands for Vulcanised Indian Rubber and no more indicates the type of cable than PVC does.