Application of Earth Leakage Relay

Use ACB with ELR built in function Schneider ACB with 7.0A release

Thanks for the promptly reply.

Is the system workable of 2500A 3p ACB with the 300-500mA ELR? Will the ELR being too sensitive for the system?

It is very difficult to use the ELR with 300 -500mA for such high current breakers. what is the application. if load is directly connected to this then you can use ELR other wise setting required will be higher.

Here settings are available upto 30A in this release of breaker.

If you are using in panel as main breaker and downstream there are multiple outgoings then use earfault at I/C and ELR at breaker close to load.

in accordance to the authorities requirement in Abu Dhabi.

The upstream LV Main Distribution Board is required to configured with ELP 300-500mA, though we have explained to the officer that ELP 300-500mA for main incoming is too sensitive and it will not workable.

And it is now we are offering only OC/EF installed as the more practical protection.

The Main Distribution Board is cascaded for the Power Distribution in accordance to the designated Fault Level required for Icu, Ics, and configured with the branching outgoing ACB, MCCB respectively.

Therefore, we would like to know seek the professional comments from the team whether the ELR is practically configured to the Main Distribution Board in this case.

Simple solution is to use earthleakage protection built-in the ACB. IN Schneider , i think its micrologic 7.

else u can use a rectangular sensor (cbct) with the ELR.

the rectangular cbct comes in different sizes . u chose them according to your breaker rating and cable size.

the elr has a wide range from 30mA to 30A with instantaneous and time delay tripping.

u can check schneider website and search for RH99M relays .

Thank you for proposal,

may i know what is the best made, model best fit for the 2500A MDB with 3Phase 4 wire system.

1. For Cable Entry

in order to fit the Core Balance CT with the 12 nos of the 630mm2/1C XLPE cable, i think we have to use the large enough CTs for it.

2. For BusDuct

Possible to use separate CTs for each phases+neutral? Or it is still require to use only the square CT.

the best solution s schneider acb nw25h2 with micrologic 7.

if you strictly wanna use elr+cbct

then go through this website and download

http://www.global-download.schneider-electric.com/852575A6007E5FD3/all/5A0A5DE903F264CF852577100022D4C0?OpenDocument&L=EN&p=1014&idxUrl=repositorySchneider\\index.nsf&XID=225304&XHOST=http://logi5.xiti.com/&HOSTIP=http://www.global-download.schneider-electric.com/&OTrSer=http://www.download.schneider-electric.com/

http://www.global-download.schneider-electric.com/85257578007E5C8A/all/4F6340B77D6927C088257578006B1B04/$File/0972ct0401.pdf

download the pdf and search for rectangular sensor (part no. 56054)

and ELR (RH99M).

I think it will match yo requirement.

Thanks for the input.

it seems like i have got TWO options on only with

1. NW25H14D2AH with Micrologic 7.0A (selective + earth-leakage protection.)

OR

2. the ACB with external ELR RH99M with Rectangular CTs

whats 4D2AH in NW25H14D2AH. i dont know the exact part no. NW25 is right . but H1 or H2 will depend on yo KA requirement .if you are in abu dhabi then contact schneider customer care (7099333).

Dear Shamith

NW25H1 = 2500A NW series ACB

4D2AH:

4 = 4 Pole

D = Withdrawable

2A = Micrologic 2.0A

H = Horizontal Connection

Only NW63 with vertical connection