by ericmark »
Fri Nov 13, 2009 9:11 pm
[quote="sparx"]hi, have to disagree with
answer 2, it is imho b)
the whole point of PAtesting is to spot early deteriation of a reading so the equipment can be taken out of service before total failure eg flex breaking down with ever lowering IR readings, which is the reason for having to keep records rather than just 'go-nogo' pass levels,
I think Ericmark misread the question,
regards Sparx[/quote]
Yes I had put in wrong letter it is of course (b) I did say the fuse has nothing to do with insulation resistance so I'll blame typo error was not looking properly at options.
All questions there are two things to look at. 5) For example says Class II so there will be no earth continuity so only two left. deterioration will lower insulation resistance values. So looking at what it's not is also important.
Although we are to look for trends the portable appliance testing is often done on the hoof so carrying all past test results to compare before the pass or fail is mainly theoretical except for where the tester stores the info.
However not all testing of in service equipment is concerned with portable equipment in the way one expects using a purpose made machine.
Each month I tested part of our portable batching plant. (It did have wheels came as 6 wagon loads) The engineer has split the testing into 4 groups designed so two men could test 1/4 per day so every 4 months all would be tested at 1 day (Sunday) per month. (Three plants and 3 guys so each guy worked every other Sunday) With such inspecting and testing all results were entered on an Excel spread sheet and insulation was monitored. Often low insulation was due to concrete dust across contacts getting damp and using a vacuum cleaner to remove dust was all part of the service.
Also items like safety switches were also included in the tests and we had to ensure removing panels would auto stop the machine. I was not just the shock dangers we tested for but also all electrically controlled safety systems.
C&G 2377 is not just items under 18 kg in mass that is intended to be moved while in operation or an appliance which can easily be moved from one place to another. It also includes the other categories. I will admit the batching plant is a little more than most people test but when one agrees to inspect and test all in-service equipment in a building one could find the odd hand dryer which is not part of building fabric but is hard wired and requires access to distribution boards to isolate and test.
Hence why some questions seem rather odd. It is of course impossible to test any ones ability with two short exams and once you start inspection and testing you will start to learn. I had all sorts of adaptors and tools to make life easy and we often wrote our own procedure including holding in contactors to do IR sets where the machines were three phase and we could not run them through the PAT tester.
Passing the exam like the driving test says your good enough to start testing you will never stop learning.