CalCards - whats peoples thoughts?

raustin · Mar 9, 2011

I've just got of these to keep a check on my MFT as reading up on the subject, seems like I need to be checking monthly (in between the yearly calibration) that the MFT is still reading OK.

Now I know thathe CalCard is to check for trends and not absolute values but I was surprised at the variation in the measured value. The resistance figures ok but I thought that insulation is a bit out. Have emailed the guy and he's responded saying that they are OK. As long as the measured figures don't drift that is all that matters. Is this correct?

Range Measured value
0.25 0.28
0.5 0.53
1.0 1.03
2.0 2.03
5.0 5.01

0.5M 0.49M
1.0M 0.99M
2.0M 1.99M
10M 9.16M
20M 19.7M

Cheers Rich

mydigitalhome · Mar 9, 2011

Always going to get a bit of variation temperature, humidity etc. if your machine has been calibrated and from that point onwards checks are carried out with a CalCard should not be a problem. If you buy a CalCard 10 months after calibration then who know. Machine may of been dropped or developed some fault. Great bit of kit for piece of mind and can save you money.

jase · Mar 10, 2011

and if you get you MFT calibrated and then use a calcard monthly, you only need it calibrating every 3 years, well at least thats what elecsa requirement is, dont know about niceic etc

thekingiam · Mar 10, 2011

never heard of cal card until this post just looked on ebay, seems a bit expensive for a couple of resistors that you can pick up for pence.
taking readings from any resistor fluctuates depending on temperature,tolerance etc the only way of testing is how they say noticing extreme vairables in readings.
i would recomend buying a few resistors of each value setting up 2 comparisons and checking regualary if wrong reading on one set of results check comparison then you can eliminate a resistor failure, also if you want to buy a few resistors that have been sandwitched between two cards then i will charge about 15 quid.

MarkieSparkie · Mar 10, 2011

and if you get you MFT calibrated and then use a calcard monthly, you only need it calibrating every 3 years, well at least thats what elecsa requirement is, dont know about niceic etc

Jase, You like a number of others on here have miss interpreted the requirements of Elecsa, NICEIC and others in respect of calibration.
All test equipment must be calibrated yearly, with the exception of check-boxes which have to be calibrated every 3 years and Cal-card have to be replaced every 3 years.
It is most definitely NOT the case that by implementing a regular checking routine that you can extend the calibration period of test equipment to 3 years.
There is also some doubt as to whether regular checking with a Cal-card and some check-boxes actually meets the guidance of GN3, or test the requirements of BS EN 61557 and BS EN61010, because it does not measure the output voltage and current of the test equipment and indicate that it is within the tolerance range set out in the relevant standard. It is argued in some legal circles that if an electrician can not show evidence of regular checking of test equipment to the relevant standard, then any test results recorded on inspection documentation is cast in doubt and by implication any other testimony given by said electrician in a court of law is also cast in doubt.

thekingiam · Mar 10, 2011

MarkieSparkie said:
Jase, You like a number of others on here have miss interpreted the requirements of Elecsa, NICEIC and others in respect of calibration.
All test equipment must be calibrated yearly, with the exception of check-boxes which have to be calibrated every 3 years and Cal-card have to be replaced every 3 years.
It is most definitely NOT the case that by implementing a regular checking routine that you can extend the calibration period of test equipment to 3 years.
There is also some doubt as to whether regular checking with a Cal-card and some check-boxes actually meets the guidance of GN3, or test the requirements of BS EN 61557 and BS EN61010, because it does not measure the output voltage and current of the test equipment and indicate that it is within the tolerance range set out in the relevant standard. It is argued in some legal circles that if an electrician can not show evidence of regular checking of test equipment to the relevant standard, then any test results recorded on inspection documentation is cast in doubt and by implication any other testimony given by said electrician in a court of law is also cast in doubt.

you have mentioned this before on another post, i would like to ask where your evidence for this is documented. The requirements for the common electricians are mostly documented in bs761 or legaly in health and safety i can not find these requirements so it does not exist in my eyes?
all this scaremongering is just leading the common electrician into buying needless **** for no reason.

thekingiam · Mar 10, 2011

oh yeah a cal card is just a couple of resistors and a proving unit is a capacitor so why the **** do you have to buy them.

rocker · Mar 12, 2011

MarkieSparkie said:
Jase, You like a number of others on here have miss interpreted the requirements of Elecsa, NICEIC and others in respect of calibration.
All test equipment must be calibrated yearly, with the exception of check-boxes which have to be calibrated every 3 years and Cal-card have to be replaced every 3 years.
It is most definitely NOT the case that by implementing a regular checking routine that you can extend the calibration period of test equipment to 3 years.
There is also some doubt as to whether regular checking with a Cal-card and some check-boxes actually meets the guidance of GN3, or test the requirements of BS EN 61557 and BS EN61010, because it does not measure the output voltage and current of the test equipment and indicate that it is within the tolerance range set out in the relevant standard. It is argued in some legal circles that if an electrician can not show evidence of regular checking of test equipment to the relevant standard, then any test results recorded on inspection documentation is cast in doubt and by implication any other testimony given by said electrician in a court of law is also cast in doubt.

I've got to back him up on this, I bought a seaward checkbox cos I thought I would have three years on my MFT calibration, but I had my yearly assessment last week and the guy wasn't having any of it. He said the Seaward checkbox has to have a three year calibration certificate itself (which, by the way, NO ONE can supply). After we were finished I found this a bit odd and rang up elecsa. I said about my box and how it's just a bunch of resistors and how the heck am I supposed to get it calibrated, and he said they wouldn't accept it anyway! When I mentioned calcard he quickly changed the subject and said about an offer they can do to get my MFT calibrated!!! To be honest I don't think they know what they are on about on this matter, but the upshot is that although they infer the calcard will give you three years on your MFT, they actually mean you can have a checkbox or calcard for three years between calibration, but you still need to get a yearly calibration on the MFT!!! So it's bloody pointless having one as you know the general resistance of a ring final in a 3 bed house and if it started going funny you'd notice it! I'll have my seaward on eBay when I have time!

Anyway I found a local guy who calibrated my DiLog for £45, which I thought was a bargain (picked it up from site and dropped it off and all)

jase · Mar 12, 2011

http://www.elecsa.co.uk/downloads/CalCardOperatingInstructions7.pdf

See right at the bottom of the page, admittedly this would only apply to a continuity/ir tester anyway so you mayaswell get your MFT calibrated yearly

SirKit Breaker · Mar 12, 2011

jase said:
and if you get you MFT calibrated and then use a calcard monthly, you only need it calibrating every 3 years, well at least thats what elecsa requirement is, dont know about niceic etc

I got conned with my Elecsa Calcard. They told me to get one and I did on the proviso that i wouldn't have to pay annually for calibration. But, the MFT still needs annual calibration for RCD, Loop, and Voltage as i was informed on the next annual surveillance visit. Anyway it does come in handy if i get a dodgy result and need to check it. And its useful to keep a check on accuracy, so its not money wasted.

Cheers.........Howard