Insulated But Not Sheathed.....

[Sidewinder]

Fine, I can help with that.

Get me the manuf' of the MCCB's etc. though.

 

[kerching]

Park Homes!...dont you just love them!

We stopped doing them years ago...back in the days of FVELCBhad one sit wher if the bloke in the far corner put his kettle,on then the pic collapsed on next doors TV

Joints buried in biscuit tins

What is NOT to like about a "flying tape joint"?

1.5 Tand E buried to each van!

Why do they all keep piles of Old Timber under their "tin boxes of joy"?

Just wondering

 

[NozSpark]

Here's a pic of the 250A MCCB

http://i222.photobucket.com/albums/dd101/nozspark/IMAG0758.jpg

 

[Sidewinder]

So getting my head around this, in a single line diagram style.

100A DNO fuses ----> 250A MCCB -----> 125A MCCB ---------> Park Homes

                                                      |

                                                     +-----> 125A MCCB ---------> Park Homes

I hope this lines up OK.

 

[kerching]

So getting my head around this, in a single line diagram style.

I READ IT AS.....

??? DNO Fuses

.

I

I

100A 3036 fuses ----> 250A MCCB -----> 125A MCCB ---------> Park Homes

                                                      |

                                                     +-----> 125A MCCB ---------> Park Homes

I hope this lines up OK.

MY INTERPRETATION in BOLD as I am on the ipad

 

[NozSpark]

DNO FUSES

100A 3036 switch fuse

250A MCCB

going to 2 x 125A MCCBs

each of which supply a db with B40A MCBs for the park homes...

BTW I'm doing a PIR without any on going remedials.....thankfully

 

[Phoenix]

It sounds like the 250A MCCB is only being used as an incommer to a panel board in conjunction with the earth leakage shunt trip, its overcurrent properties are not relevant. The board is protected by the upstream 100A 3036 fuses.

Are the outgoing cables from the 125A breakers suitable for 125A

Of course there is not much discrimination in the system!

What are the settings on the earth leakage shunt trip?

As to testing the earth leakage shunt trip, I am not sure what else to suggest other than making sure you have got the tester set to S type. As stated a delay >600ms is quite possible with most devices. Never had a problem testing these, however I use a RCDT320 rather than an all in one, perhaps the all in one is tailored towards testing fixed delay domestic type S rcds??

 

[NozSpark]

I agree that the 250A MCCB is just being used in essence as a RCD

However there is zero discrimination between the 125A MCCBs and the 100A 3036s

I even turned down the delay on the Earth Leakage Relay and it still tripped >600ms,,,, I did have my meter set to the delay settings but maybe it us more suited to S type RCDs

 

[SLIPSHOD & SLAPDASH]

I have seen quite a few feeder pillars with one of those photocells that fits in a 20mm hole mounted in the side with single cores attached, mainly crimped through going to a contactor. I always thought its wrong as whoever is the nearest or is boiling a kettle is the one who has to reset the always tripping rcd. Normally a not competent person.

On a side note, looking at this tonight on my tablet your first lot of pics are not there, bad link and the second post took me to load of spam advertising, last breaker pic ok.