high pfc

[essexboy]

can anyone help?

3phase service head to block of flats,TN-cs earthing arrangement,80 amp cut out feeding 1st flat

tested Pssc = >19.9ka
tested pefc = >19.9ka
tested ze = 0.01

mcbs only rated at 6ka, do i have a problem?????

would appreciate any answers

 

[Guest123]

Hi.

Sounds like your very close to the supply transformer.

Where did you take this measurement??? Is there a panel board with MCCB's protecting the submains??? Or is it a ryefield unit??? MCCB's to BS 60947-2 are rated to 25KA and BS1361 type 2 fuses are rated to 33KA

Can you give a bit more info please.

 

[essexboy]

hi lenny

the pssc/pefc measurements were taken at the customers cu on the incoming line/neutral & earth all bonds in place and Ze taken with incoming earth disconnected from met

its a it a ryefield unit with BS1361 type 2 80 amp fuse

like you said ,it could be very close to the transformer but i`am not to sure to put on the eic

cheers

 

[bluesky]

possibly you meter is on the wrong setting or needs calibrating/repair.

 

[essexboy]

its a posibility blue sky ,theres 2 old meters (1 for economy 7),but is there anyway of confirming that the problem lies with the meters?? the e-on engineer did say that the meters could do with changing but how would this affect the readings?

 

[ian.settle1]

its a posibility blue sky ,theres 2 old meters (1 for economy 7),but is there anyway of confirming that the problem lies with the meters?? the e-on engineer did say that the meters could do with changing but how would this affect the readings?

He means the test meter needs recalibrating not the supply meter

 

[bugsy]

its a posibility blue sky ,theres 2 old meters (1 for economy 7),but is there anyway of confirming that the problem lies with the meters?? the e-on engineer did say that the meters could do with changing but how would this affect the readings?

I FINK he is refering to your test instrument - not the supply meters,

 

[essexboy]

arh see what your saying now dont think its going to be anything wrong with my tester,only had it calibrated a few weeks ago....ive got a megger 1552 for pssc/pefc it was set to pfc/hi setting and ze it was set to loop/hi setting as normal???

 

[bluesky]

probably need to contact local supplier to get Ze， it is really small..

 

[ian.settle1]

How close is the DNO transformer you could be right on top of it with a readin like that.

 

[essexboy]

thanks for all your replys

i think i will ring the dno and see what they say, hopefully they will be more helpful than they usaully are what should i put on the eic....the rating of the cut out fuse 33ka???

 

[trix]

From a previous post:
If you have protection from the rec, a 1361 type 2, and a consumer unit which
incorparates a main switch to current B.S. you are allowed to rely on the breaking capacity
of the 1361. Other factors are involved, but the general rule applies to
domestic installations. This is in the reg's and the onsite guide and GN3