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Pete999

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I have searched and am at a loss, does anyone know the regulation number (if there is one) regarding fitting MCBs into a Consumers Unit that is of a different Manufacturer, as an example only, I have a BG CU and the only replacement MCB I can find is a MEM one. There is a thought that this is not allowed under BS 7671, anyone got any views, or information?
 
I have searched and am at a loss, does anyone know the regulation number (if there is one) regarding fitting MCBs into a Consumers Unit that is of a different Manufacturer, as an example only, I have a BG CU and the only replacement MCB I can find is a MEM one. There is a thought that this is not allowed under BS 7671, anyone got any views, or information?
There’s thousands of BG circuit breakers on the market. They are still in manufacture today.

LMGTFY - http://bfy.tw/Kj7i
 
Well it is a regulation under 7671, but I wonder if you can provide evidence that it is of equal quality etc that it could be allowed as a deviation of regs?
 
Suggestions are made in several places....

536.4.201 Fault current (short-circuit) ratings
The relevant fault current (short-circuit) rating of the assembly should be equal to or exceed the maximum prospective fault current at the point of connection to the system.

The terminology used to define the short-circuit rating of an assembly is given in the BS EN 61439 series as follows:
- rated short-time withstand current, Icw
- rated peak withstand current, Ipk
- rated conditional short-circuit current, Icc.
The assembly manufacturer’s ratings and instructions shall be taken into account.

For an installation with a 230 V single-phase supply rated up to 100A that is under the control of ordinary persons, switchgear and controlgear assemblies shall either comply with BS EN 61439-3 having a suitable fault current (short-circuit) rating for the maximum prospective fault current at the point of connection to the system or be a consumer unit incorporating components and protective devices specified by the manufacturer complying with BS EN 61439-3, including the 16kA conditional short-circuit test described in Annex ZB of the standard.

536.4.203 Integration of devices and components
The relevant part of the BS EN 61439 series shall be applied to the integration of mechanical and electrical devices and components, e.g. circuit-breakers, control devices, busbars into an empty enclosure or existing low voltage assembly.

In low voltage assemblies to the BS EN 61439 series, e.g. consumer units, distribution boards, incorporated devices and components shall only be those declared suitable according to the assembly manufacturer’s instructions or literature.

NOTE 1: The use of individual components complying with their respective product standard(s) does not indicate their compatibility when installed with other components in a low voltage switchgear and controlgear assembly.
NOTE 2: Incorporated components inside the assembly can be from different manufacturers. It is essential that all incorporated components should have had their compatibility for the final enclosed arrangements verified by the original manufacturer of the assembly and be assembled in accordance with their instructions e.g. the consumer unit, distribution board manufacturer. The original manufacturer is the organization that carried out the original design and the associated verification of the low voltage switchgear and controlgear assembly to the relevant part of the BS EN 61439 series.

If an assembly deviates from its original manufacturer’s instructions, or includes components not included in the original verification, the person introducing the deviation becomes the original manufacturer with the corresponding obligations.


And it's included in section 7 of the model schedule of inspections.
 
Old thread here that might be of interest?

Oh yes, there has never been a prohibition against this practice until AMD3.
The two conditions preventing this practice has always been compatibility and breaking capacity.
The breaking capacity of the individual components of a CU has frequently been lower than the PFC of many installations.
To circumvent this, they introduced ‘Type testing’ which increased the overall breaking capacity of CUs to 16kA.
Mixing different manufacturer’s components negates the type testing. As such unless the breaking capacity of the individual components was greater than the PFC, mixing manufacturers’ components was prohibited.
However in non-domestic installations where breaking capacities of individual components are generally much higher, this has never been much of a problem.

Amendment 3 of the 17th edition however changed things.
It introduced the requirement for BS EN 61439-3 CUs to be used in domestic installations.
BS EN 61439-3 CUs are type tested and as such the requirement effectively prohibits the mixing of manufacturers’ components.
Again in non-domestic installations, not so much of a problem.

If this new requirement prohibits the mixing of manufacurers’ components altogether, it may well have far reaching consequences. Not a only affecting standard DBS and CUs, but also custom built switch panels and control gear.
Will we still be able to build a control panel containing Telemecanique relays with ABB VSDs and Shneider MCBs?
 
Suggestions are made in several places....

536.4.201 Fault current (short-circuit) ratings
The relevant fault current (short-circuit) rating of the assembly should be equal to or exceed the maximum prospective fault current at the point of connection to the system.

The terminology used to define the short-circuit rating of an assembly is given in the BS EN 61439 series as follows:
- rated short-time withstand current, Icw
- rated peak withstand current, Ipk
- rated conditional short-circuit current, Icc.
The assembly manufacturer’s ratings and instructions shall be taken into account.

For an installation with a 230 V single-phase supply rated up to 100A that is under the control of ordinary persons, switchgear and controlgear assemblies shall either comply with BS EN 61439-3 having a suitable fault current (short-circuit) rating for the maximum prospective fault current at the point of connection to the system or be a consumer unit incorporating components and protective devices specified by the manufacturer complying with BS EN 61439-3, including the 16kA conditional short-circuit test described in Annex ZB of the standard.

536.4.203 Integration of devices and components
The relevant part of the BS EN 61439 series shall be applied to the integration of mechanical and electrical devices and components, e.g. circuit-breakers, control devices, busbars into an empty enclosure or existing low voltage assembly.

In low voltage assemblies to the BS EN 61439 series, e.g. consumer units, distribution boards, incorporated devices and components shall only be those declared suitable according to the assembly manufacturer’s instructions or literature.

NOTE 1: The use of individual components complying with their respective product standard(s) does not indicate their compatibility when installed with other components in a low voltage switchgear and controlgear assembly.
NOTE 2: Incorporated components inside the assembly can be from different manufacturers. It is essential that all incorporated components should have had their compatibility for the final enclosed arrangements verified by the original manufacturer of the assembly and be assembled in accordance with their instructions e.g. the consumer unit, distribution board manufacturer. The original manufacturer is the organization that carried out the original design and the associated verification of the low voltage switchgear and controlgear assembly to the relevant part of the BS EN 61439 series.

If an assembly deviates from its original manufacturer’s instructions, or includes components not included in the original verification, the person introducing the deviation becomes the original manufacturer with the corresponding obligations.


And it's included in section 7 of the model schedule of inspections.
Thank you SC
 

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