MK SENTRY 5945s Breaker problem

[danny124]

Hi guys need help, not mentally though haha...

Er, i dont usually use MK but i used it for one job and have a problem....

Did all the test, all ok, got to office and found out the 5945s MK sentry 45amp breaker doesnt have a earth fault loop impedance Zs number in the BRB7671 or my 80% value on my test sheet pack.

extensive searching on the net, and found that it is a TYPE B, but there is no value on it for my test certificate.

Can anyone help, have i done something wrong, or is it a differant type like a 1 or 2. Im just out of ideas

Cheers guys and thanks for your time

 

[rmaynard]

its still a bs en 60898, the mk5945s is the mk model number. Max Zs is 0.82 un-corrected

Rob

 

[danny124]

Hey rmaynard thanks for that... I know the 5945s is the model number, and had a feeling it was 60898, but when i looked in thr brb it had nothing for a 45amp type b...

Where did you find the Zs value

Thanks again

 

[rmaynard]

It's in the addenum on the iet website

 

[danny124]

ah right, cool. Thanks again...

 

[telectrix]

I made it 1.022 uncorrected, 0.82 at 80% corrected

 

[telectrix]

easy way
to work it out if you not got regs or osg with you

max. Zs for a type B60898 MCB Zs= 230(volts)/ ( In x 5 ) ohms law. for C type the factor is 10.

so in the case of you 45A: max. Zs= 230/(45 x 5) i.e. 230/225 = 1.022.

 

[Lou7]

Look in Regs book at the end of each line Table 41.3 BS60898
B type 46/In
C type 23/In
Dtype 11.5/In
46/45 = 1.02