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I have to say, it's nice to see a poster actually giving us all the info we need, along with his own opinions and calculations.
Are you planning to use 2-core swa, with the armour as your cpc?
Also, if the swa enters the building close to the CU, it is much easier to take it straight to it, thus eliminating the T&E at the house end. If you are using 3-core, then your cpc will be 10mm anyway so even tidier.
 
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I have to say, it's nice to see a poster actually giving us all the info we need, along with his own opinions and calculations.
Thanks! I know it's a long one & if I was 200% I wouldn't have gone to all the typing! But I only sub occasionally as a Mate to another Guy & I don't always get what I'm after. That's more down to more ways to skin a cat & how it's always been done. I was asked to take a look & have done. If I felt completely out of my depth I'd have declined it. Just wanted to run it by & gain some thoughts ensuring I was on the right path...
 
I don't think I can get around the discrimination with the RCD at the Distribution CU in the house. 16th Board, all circuits protected. He won't go for a Board change to allow me to put on the unprotected via an RCBO. If I was to use an MCB for the supply SWA to the CU in the Garage, if that CU was RCD'd (all circuits surface in Conduit, so no real need) would there be a time delay in the event of an Earth Fault here due to the 50m run? IE, the Garage would go first? Or not?
 
Are you planning to use 2-core swa, with the armour as your cpc?
Also, if the swa enters the building close to the CU, it is much easier to take it straight to it, thus eliminating the T&E at the house end. If you are using 3-core, then your cpc will be 10mm anyway so even tidier.

I had planned on 3 core & still fly leading the Armoured. The Dis Board in the house is at ceiling height, about a 2m drop & 1m round to the outside wall. So felt T&E in Trunking was a neater option (or rather best option).
 
Max Zs for a 63A type B is 0.73.

Max CCC for 10mm T&E is 64 A clipped direct, enclosed in trunking is 52A.
 
One thought, have you asked about how the spray booth is used?

1.5kW is a HUGE fan and will move a lot of air. Certainly more than a 2.5kW heater will be capable of heating up by any meaningful amount. Is the heater being used when the fan is running? If not then the main load will be either:
1. Extract and compressor when spraying
2. Heater alone when baking?

Not sure if this helps but worth checking.
 
I don't think I can get around the discrimination with the RCD at the Distribution CU in the house. 16th Board, all circuits protected. He won't go for a Board change to allow me to put on the unprotected via an RCBO. If I was to use an MCB for the supply SWA to the CU in the Garage, if that CU was RCD'd (all circuits surface in Conduit, so no real need) would there be a time delay in the event of an Earth Fault here due to the 50m run? IE, the Garage would go first? Or not?
if its a TN system...then why put an RCD on the feed upstream?...use an armoured and RCD it downstream....or you could go for a 100mA s type feed....30mA downstream end.....
 
his problem is that the house has a 30mA RCD front end. unless he can split the tails at the main CU and feed from there, he's stuffed.
 
his problem is that the house has a 30mA RCD front end. unless he can split the tails at the main CU and feed from there, he's stuffed.
yes sorry...just re-read the post...i think he`s on about earth leakage......if you have 2 RCDs in series....say both 30mA..with similar individual traits.....the one upstream SHOULD let go first under fault as its also being subjected to any earth leakage from other finals and/or subs it serves....
 
Max CCC for 10mm T&E is 64 A clipped direct, enclosed in trunking is 52A.

Looks like I'll be taking the Armoured into the house. Thanks for pointing out Lenny...

Rather than have the SWA Cleated up to the board at ceiling level, could I terminate into the adaptable box & strip back to the insulated conductors making them long enough to then have those in trunking?? No method for installing like that, so assume a NO? Going to look offensive as the board is ceiling height, 1m in from the external wall with the spare way access on the left. Was going to come down vertically to skirting & round to existing opening...
 
One thought, have you asked about how the spray booth is used?

1.5kW is a HUGE fan and will move a lot of air. Certainly more than a 2.5kW heater will be capable of heating up by any meaningful amount. Is the heater being used when the fan is running? If not then the main load will be either:
1. Extract and compressor when spraying
2. Heater alone when baking?

Not sure if this helps but worth checking.

Yeah I think he said the Fan & compressor together. The Heater would I imagine be used stand alone. I assume you are asking due to the ventilation query & not with regards to the demand of the install?
Cheers!
 
Yeah I think he said the Fan & compressor together. The Heater would I imagine be used stand alone. I assume you are asking due to the ventilation query & not with regards to the demand of the install?
Cheers!

So is it possible to put the heater and fan on a changeover switch. This will reduce possible maximum loading? And still allow compressor to run at all times for air tools etc.

I admit I am not an electrician but a HVAC engineer that does a lot of design work on systems involving heaters and fans...............
 
could I terminate into the adaptable box & strip back to the insulated conductors making them long enough to then have those in trunking?

absolutely nothing wrong with that method. just have to ensure you get a good connection to the armour in the ad. box. with a fly leadand banjo or earth nut.
 
absolutely nothing wrong with that method. just have to ensure you get a good connection to the armour in the ad. box. with a fly leadand banjo or earth nut.
Tel - Thanks for all your time on this tonight! Appreciate it! I got recommended to Wiska Boxes with the Gland Clamp, so gonna use those as they look easy & a good connection.
 
Tel - Thanks for all your time on this tonight! Appreciate it! I got recommended to Wiska Boxes with the Gland Clamp, so gonna use those as they look easy & a good connection.

They are indeed easy to use and come in either black or grey. Using any box fixed to the CU and passing the cores through will make life much easier when using larger swa (domestic-wise at least). The gland clamp makes a flying lead very easy to connect. One word of caution tho, the outer fixings on the base part of the wiska boxes are quite thin and easy to break off if you're not careful!
 
I think you maybe right, even though Acetone is a standard thinner it may be that the more common/cheaper chemical is Cellulose.

However, I grabbed this off of another forum and looks quite interesting: which can be read in its entirety here: what's in cellulose thinners?

Q: i've bought a couple of the cellulose thinners from halfords before, fine, they're convenient. but this time i decided to get a 5 litre drum of it. went to the paint shop, and the guy said it was fine for cleaning and spraying.

the halfords one smells quite nice lol and is perfectly colourless
this new one is rank, and slightly yellow. its says on the bottle 'contains toulene'. is toulene the main thing in cellulose thinners?


A: Toluene, also known as methylbenzene, or Toluol, is a clear water-insoluble liquid with the typical smell of paint thinners, reminiscent of the related compound benzene. It is an aromatic hydrocarbon that is widely used as an industrial feedstock and as a solvent. Like other solvents, toluene is also used as an inhalant drug for its intoxicating properties; however, this causes severe neurological harm.

Toluene reacts as a normal aromatic hydrocarbon towards electrophilic aromatic substitution.[3][4][5] The methyl group makes it around 25 times more reactive than benzene in such reactions. It undergoes smooth sulfonation to give p-toluenesulfonic acid, and chlorination by Cl2 in the presence of FeCl3 to give ortho and para isomers of chlorotoluene. It undergoes nitration to give ortho and para nitrotoluene isomers, but if heated it can give dinitrotoluene and ultimately the explosive trinitrotoluene (TNT).


I think the fan should run constantly while the heating process is in effect !
 
I think you maybe right, even though Acetone is a standard thinner it may be that the more common/cheaper chemical is Cellulose.

However, I grabbed this off of another forum and looks quite interesting: which can be read in its entirety here: what's in cellulose thinners?

Q: i've bought a couple of the cellulose thinners from halfords before, fine, they're convenient. but this time i decided to get a 5 litre drum of it. went to the paint shop, and the guy said it was fine for cleaning and spraying.

the halfords one smells quite nice lol and is perfectly colourless
this new one is rank, and slightly yellow. its says on the bottle 'contains toulene'. is toulene the main thing in cellulose thinners?


A: Toluene, also known as methylbenzene, or Toluol, is a clear water-insoluble liquid with the typical smell of paint thinners, reminiscent of the related compound benzene. It is an aromatic hydrocarbon that is widely used as an industrial feedstock and as a solvent. Like other solvents, toluene is also used as an inhalant drug for its intoxicating properties; however, this causes severe neurological harm.

Toluene reacts as a normal aromatic hydrocarbon towards electrophilic aromatic substitution.[3][4][5] The methyl group makes it around 25 times more reactive than benzene in such reactions. It undergoes smooth sulfonation to give p-toluenesulfonic acid, and chlorination by Cl2 in the presence of FeCl3 to give ortho and para isomers of chlorotoluene. It undergoes nitration to give ortho and para nitrotoluene isomers, but if heated it can give dinitrotoluene and ultimately the explosive trinitrotoluene (TNT).


I think the fan should run constantly while the heating process is in effect !
some interesting stuff on google about picric acid and nitrocellulose compounds as well...lol....
 
Using any box fixed to the CU and passing the cores through will make life much easier when using larger swa (domestic-wise at least).
Just been mulling this over as there's a few ways I could do this. Until I speak to the Guy I won't know which way to jump.
Options:
a) Gland SWA outside of the house & strip off Armoured leaving sheathing until it enters the house into white trunking & run up to CU. Will need to bring in a long 10mm flylead off the armoured too, about a 3m run.
b) Gland SWA into adaptable box next to CU, short flylead with SWA Clipped direct on show
c) As per b, but house the Vertical run of SWA in suitable trunking

Quite liking option c for tidiness...think a length of trunking is neater on show than cleated armour inside the house.
 

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