A little help please.

[markhughes]

Just received a couple of Electrical Danger Notifications (C2's) from our annual electrical inspections.

"No co-ordination between conductor and protective device cct 1T/P 2.5mm - 32A 3Ø ref method B"

&

"High values of measured EFLI at ccts 6TP-15TP"

Could you offer some advice as to what these mean, as I'd like to have some understanding before I talk to our electrical contractor.

Thank you in advance.

 

[telectrix]

1 seems like an undersized earth conductor (cpc). it's a bit vague

2 is a high reading of the earth fault path on several circuits.

 

[gutterball]

Is No1 saying it's the wrong breaker for the circuit? 'ref method B'
Agree with tel a bit vague. have you more info?

 

[Andy78]

The person issuing the report should be explaining any issues so they are understood by the customer. Ask for clarification.

Issue 1 is saying that the cable used for the circuit is too small for the circuit breaker and vice versa. Simplest fix is to change the breaker size if the connected load will allow.

Issue 2 is saying the earth fault path of several circuits is not sufficient. Extra or larger earth conductors could be added or the size of circuit breakers reduced again if loads will allow.

 

[markhughes]

Is No1 saying it's the wrong breaker for the circuit? 'ref method B'
Agree with tel a bit vague. have you more info?

Thank you for your reply gutterball. That's all the information written for the condition along with the regulation number 433.1.1

 

[markhughes]

The person issuing the report should be explaining any issues so they are understood by the customer. Ask for clarification.

Thank you for your reply Andy. I agree there should have been more information or at least some advice instead of just quoting the relevant regulation. I'll contact the inspection engineers and discuss with them.

 

[malcolmsanford]

Just received a couple of Electrical Danger Notifications (C2's) from our annual electrical inspections.

"No co-ordination between conductor and protective device cct 1T/P 2.5mm - 32A 3Ø ref method B"

&

"High values of measured EFLI at ccts 6TP-15TP"

Could you offer some advice as to what these mean, as I'd like to have some understanding before I talk to our electrical contractor.

Thank you in advance.

Not quite sure in what context he is using coordination, there is no hyphen in the word. Not sure a 2.5mm cable and a 32 amp MCB can be classed as a "complex body but maybe as an activity"

Think it was an attempt of BS baffles brains

 

[bigspark17]

1- overload protectice device is too high for current carrying capacity of cable
2- efli is too high, you could reduce mcb size, upgrade cable size or install rcd 30mA on circuit which will give you max zs of 1667ohms.

 

[markhughes]

1- overload protectice device is too high for current carrying capacity of cable
2- efli is too high, you could reduce mcb size, upgrade cable size or install rcd 30mA on circuit which will give you max zs of 1667ohms.

Thank you for you reply bigspark. With all the other replies, a little reading and having a good look at the circuits in question I've come to the same conclusion. Many thanks

 

[ruston]

If this is an ANNUAL report and the observations were not included in last years report there must be something remiss with any additions you have had done, or these observations have not been observed in the previous report.
If it is a breaker , or high efli on multiple circuits it is strange.

I must admit it is vague.

 

[Brightspark2]

If this is an ANNUAL report and the observations were not included in last years report there must be something remiss with any additions you have had done, or these observations have not been observed in the previous report.
If it is a breaker , or high efli on multiple circuits it is strange.

I must admit it is vague.

The max Zs values are now lower than they were in previous years with the new amendment...

 

[Brightspark2]

Not quite sure in what context he is using coordination, there is no hyphen in the word. Not sure a 2.5mm cable and a 32 amp MCB can be classed as a "complex body but maybe as an activity"

Think it was an attempt of BS baffles brains

It's how it's listed in the schedule of inspection now though isn't it.

Coordination of over current protective devices and cable size...or something along them lines...

 

[Simonslimline]

If an RCD is already present in the system then it could be effecting the Zs readings. Had this multiple times and bypassing it or using the alternative Zs method proved it to be the RCD.

Obviously this depends on the current set up and if it is RCD protected or not.

One other thing regarding Zs values, If carrying out an EICR on an installation that was installed to say the 17th before any AMD's then if the circuits tested met these values then surely it complies to the edition/AMD it was installed to?

 

[malcolmsanford]

It's how it's listed in the schedule of inspection now though isn't it.

Coordination of over current protective devices and cable size...or something along them lines...

Yes you are spot on ...............coordination between conductors and overload PD's so hats off to the inspector on that one....and you Bright