Insulation Test before consumer change.

[ZippyMo]

Guys

Is it good practice to zap the old wiring with a 500 volt insulation test before any consumer unit is installed?
Or do you just go ahead and rip out the old one and fit the new?

Zippy

Trainee Sparky

 

[The Ghost]

Might be a tad more than that before I change a consumer unit.

 

[Richard Burns]

You really want to do as much inspection and testing as you can prior to changing a consumer unit to ensure that you are not having to deal with any pre-existing problems.
Ideally an EICR beforehand, but if the customer will not agree then at the very least inspection, Ze and insulation resistance tests.
When reconnecting circuits to a new consumer unit you need to ensure that they are safe to reconnect, to find out they are not safe during a consumer unit change could mean you either do not reconnect a vital circuit or spend a lot of your time for free fixing unrelated faults.

 

[Gavin John Hyde]

if worried about something connected that you didnt disconnect do the IR at 250v, check your end to ends on any rings or RFC if we are being all proper. usual Ze, check the bonding to gas and water.
Check for borrowed neutrals - most often found on landing 2 way lighting. can be a pain in arse to correct if you are adding rcds in where there were none previously.
Last but not least say 'I wish' three times in quick succession for the seal fairy to come and magically pull the fuse! when the fuse looks old and potentially a bit iffy or hard to pull out they often dont come so you have to get the DNO to come instead. If there is an isolator switch the seal fairy also wont come as they have an aversion to them.

 

[Pete999]

Might be a tad more than that before I change a consumer unit.

What he said, ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

 

[The Ghost]

It all depends on what the installation looks like age wise and wear and tear wise. I essentially offer the customer a choice. One is where I do an EICR to find any defects then rectify them then change the DB. Two I change the box and deal with any defects encountered as I go. Usually they choose the latter. As I say that offer is dependent on age and wear and tear if it is obviously (to me) a rewire job then I do not make such an offer.