Toolbox Talk July 2023
“Good Earth” Test (Earth Loop Impedance – Ze test)
Historically, catering technicians have tested the electrical safety of an appliance – not the circuit to which the appliance might be connected. However, it’s clear from our experience on site that there are regular instances of missing or inadequate earth wiring. In order to protect ourselves and our customers, it’s vital that we ensure that the appliance which relies on a “Good” earth for safety, is indeed connected to one.
NB it may be that this test trips local circuits (The Martindale EZ650 is a no trip RCD socket tester if it trips the circuit you need to advise the customer to get the circuit tested by an
electrician as this is an indication that there is already earth
leakage on the circuit). – you should always check with the
customer before testing. Making sure you document on your
job sheet and get it signed if the customer doesn’t want it carried out so they can take responsibility.
“Good Earth” Test – How to test using a Martindale EZ650 – THIS IS A LIVE TEST.
You can either use the 13A plug lead for testing sockets or the 3-wire lead to test fixed appliances. (Both leads supplied)
- plug in the socket tester to the appropriate socket, it will do a self-test first & then will show you whether or not it is wired correctly, whether there is a fault in the wiring & what the earth loop impedance is (Green is Good, Red is not)
- Using the 3-wire lead for fixed appliances connect the green clip to earth, black to neutral and red to live in that order (Circuit needs to be live), it will do a self-test first & then will show you whether or not it is wired correctly, whether there is a fault in the wiring & what the earth loop impedance is (Green is Good, Red is not)
WE MUST ALWAYS TEST THE PRIMARY SOURCE WHERE POSSIBLE.
If we are unable to test the primary source, we must remove any supplementary bonding before this test is completed at the appliance as this may give us a false reading. If we are unable to remove all supplementary bonding i.e. A suited kitchen or solid copper pipes to the sink unit connected to the dishwasher we need detail this on-the-job sheet and complete the test.
The below is from Sunningdale golf club, Due to supplementary bonding this unit passed our GOOD EARTH TEST although as you can see the earth wasn’t connected. This has been signed off at least twice by our technicians.
By reading and acknowledging this document, you confirm that you have read and understood the content. By reading and acknowledging this document on Breathe, you confirm this is the equivalent to your signature and this will be date stamped and there will be a requirement for you to acknowledge this on an annual basis.
