Pete's Videos Terminating MICC

Easy,Pete...all modern tool-belts,have an attachment for fitting the workmate to....

I am surprised he didn't have the tool that crimps the pot in to stop the black plastic bit falling out again

bill01803 said:

I am surprised he didn't have the tool that crimps the pot in to stop the black plastic bit falling out again

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I disagree with the method of installing the seal and the compound, always told to fit the seal plastic temporarily to align the conductors, lift it away from the pot, and then fill with compound, but I suppose matey learnt to do it this way, probably knows no better.

Yeah, I think balance the workmate on the top step would be the best, holding onto it with one hand.

Re the seal, same here Pete fit it over the ends then pull off to the check the cores.

The first M.I I did had beads that went into the end of the sleeve to stop it pulling through the seal, which I'm sure was bakerlite.

When you pushed the seal down the cores spread and separated because of the beads.
It was only when they brought out the seal type in the video that you had to check the cores.

There was another type where the sleeve had an end preformed to mimic the bead.

Pete999 said:

I disagree with the method of installing the seal and the compound, always told to fit the seal plastic temporarily to align the conductors, lift it away from the pot, and then fill with compound, but I suppose matey learnt to do it this way, probably knows no better.

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Yes I agree, and I'd have tested it before filling with compound too, it's a bit late to find out you've got a problem after it's been filled and sealed!

He didn’t mention doing an IR test before filling with compound, or about heating the cable to remove moisture.

Pete999 said:

I disagree with the method of installing the seal and the compound, always told to fit the seal plastic temporarily to align the conductors, lift it away from the pot, and then fill with compound, but I suppose matey learnt to do it this way, probably knows no better.

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How about posting a youtube vid on how it should be done. Everyday a learning day.

Spoon said:

How about posting a youtube vid on how it should be done. Everyday a learning day.

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If I could find one I would, Spoon

This one isn't bad, even shows testing the seal fit;

snowhead said:

This one isn't bad, even shows testing the seal fit;

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Trying to post that one Mate but internet went haywire, Virgin

Test when the pot goes on visually and with a meter, align conductors with seal lift seal fill with compound press seal down if it's not right lift add more compound test then crimp.

Never had one fail in my time.

snowhead said:

This one isn't bad, even shows testing the seal fit;

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Those strippers where sh1te,

spinlondon said:

He didn’t mention doing an IR test before filling with compound, or about heating the cable to remove moisture.

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You don't really need to test before filling, though it will show silly things like direct shorts, and although I do heat cables witch have had long term moisture ingress it really isn't needed in most normal cases, even when the cable has been stored unsealed, stripping the cable usually removes the damp which in modern MI is absorbed very slowly.

Fit the seals to both ends, give a quick insulation test, as long as it is at least in the the 10s of Mohms and the seals have been fitted properly it will likely be good. Insulation test after 24-48 hours to confirm and you will find the insulation resistance will have increased to 'infinity'. If it hasn't, either a seal has been poorly fitted or the cable has pinholed or has other damage. A bad seal can be found by insulation testing and applying gentle heat to the cable where it enters the pot, the reading will change when a bad seal is heated. Of course for new cable the readings would normally be very high immediately.

To prove this to an apprentice I recently took a 3m length of old unsealed cable that I had pulled out of somewhere and I had stored in the garden shed. I stripped 6" of sheath off of each end and fitted the pots. The first insulation tests gave readings of 17Mohm between conductors and sheath and about 24 Mohm between conductors. Testing again 2 days later and the readings were >2000 Mohms for all tests, including testing at 1000V. I did something similar making an MI pendant set 4 years ago, the readings are still >2000Mohms today, after starting fairly low.


MICC is an amazing and incredibly robust wiring system, I use it whenever I can.