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Discuss Max Zs value for MCCBs in the Electrical Talk - All Other Countries area at ElectriciansForums.net

Hi Guys,
in an installation with one main Distribution board and several submain-DBs, do when you measure Zdb on a submain-DB incomer? and do we need to verify the Zdb value with the upstream protection device?( for example, a 250A, MCCB on the MDB outgoing). If yes, how can I get the max Zs values for MCCBs ?
Thanks,
 
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Yes you do need to measure it. Or in the UK you do, unsure of the regulations in the UAE, although projects I know about follow UK standards.

Zs Values can be gotten from the manufacturer. Normally have the information in pdf form on their website.
 
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  • #3
Yes you do need to measure it. Or in the UK you do, unsure of the regulations in the UAE, although projects I know about follow UK standards.

Zs Values can be gotten from the manufacturer. Normally have the information in pdf form on their website.
Thanks, yes we do follow BS regulations here. So I need to contact the manufacturer :thumbsup:
 
Thanks, yes we do follow BS regulations here. So I need to contact the manufacturer :thumbsup:
The max Zs is because it’s the device manufacturers specification.

I write EICR’s using the Amtech Fast test software (now known as Trimble Fast Test)
So long as you don’t have the budget version it comes with the their single line calculator.
Using single line calculator you can do the cable calls for lots of different cables and use it to obtain the max Zs for MCB’s, MCCB’s and ACB’s.

(Currently budget version is £185, version with single line calculator is £385 and expensive version is £585]
 
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  • #5
The max Zs is because it’s the device manufacturers specification.

I write EICR’s using the Amtech Fast test software (now known as Trimble Fast Test)
So long as you don’t have the budget version it comes with the their single line calculator.
Using single line calculator you can do the cable calls for lots of different cables and use it to obtain the max Zs for MCB’s, MCCB’s and ACB’s.

(Currently budget version is £185, version with single line calculator is £385 and expensive version is £585]
Thank you. had heard about Amtech but didn't know it has Zs values for breakers as well :thumbsup:
 
Thank you. had heard about Amtech but didn't know it has Zs values for breakers as well :thumbsup:
With the Amtech Fastest it automatically fills in BS 60898 and BS 3871 MCB’s, BS 88 fuses but not BS 60947 MCCB’s.

To get the unusual fuses, MCCB’s ACB’s you need the Amtech Single Line Calculator. If you get the budget version of Amtech Fastest, it is not included. Get the mid-cost or the expensive version. The Single Line Calculator is included free of charge.


I hope this helps
 
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  • #7
With the Amtech Fastest it automatically fills in BS 60898 and BS 3871 MCB’s, BS 88 fuses but not BS 60947 MCCB’s.

To get the unusual fuses, MCCB’s ACB’s you need the Amtech Single Line Calculator. If you get the budget version of Amtech Fastest, it is not included. Get the mid-cost or the expensive version. The Single Line Calculator is included free of charge.

I hope this helps
Thank you. Or probably better( cheaper) to contact more commonly used MCCB manufacturers and ask for the data.
 
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