self test citcuit

[DirtyDog368]

Hello, has anone set up the office circuit for equipment testings.

If so would you let me have a schematic so i can build my own.

thanks

DD

 

[Blowcat]

What it is your doing?

 

[Marvo]

I don't understand what you're asking I'm afraid.

 

[DirtyDog368]

I was a bit hasty at first so I will expalin in greater detail.

I have megger 1558 multi function tester.

I have to show that it is accurate. One way os to have it certified years by megger or keep records yourself.

I want to do the later which means i have to set up a home made circuit with which to test the device. (I think this is correct)

Regards

DD368

 

[Sintra]

Easier just to buy a cheap cal card.

 

[JD Hogg]

I think you will find that you will still have to have it calibrated yearly. You will need a check box/circuit/card to test the megger monthly to show that it still reads correctly throughout the year

 

[Blowcat]

The OSG section 4.2 (2) pg 81 has info on calibration or using a check box method for ongoing accuracy.

There are a lot of people who will not like you using a non calibrated tester.
If they are paying for testing they wanna see that magic sticker.
I always use a calibrated tester, its also good to get that cert for when companies ask for it, giving then a copy of your own monthly calibrations may not go down to well.
There might be a previous thread on this subject???

 

[Deleted member 26818]

Whilst 'self calibration' may well be acceptable, for domestic work and Part P scheme registration.
On larger sites and social housing landlords, the calibration certificate seems to be all they're interested in.

 

[IQ Electrical]

Have a read of this guide on calibration and the importance of regular checks:

http://www.esc.org.uk/fileadmin/user_upload/documents/industry/best_practice/BPG7_10.pdf

 

[ban-all-sheds]

If you get it calibrated, and immediately start logging regular checks of a set of known resistances etc, then if the readings stay the same you know the thing is still working fine.


If it drifts, get it re-calibrated.


When you get it back again, if it's still at odds with your check box then you need a new check box.

You can buy a cheap card.

You can buy one of those Seaward jobbies that cost as much as your b****y tester itself.

Or you can roll your own, which has got to be more satisfying.

A small hobby box, some good quality 4mm sockets, a bunch of resistors - low values for continuity and high values for IR (make sure they are 500V rated).

Put a plug and flex on the box supplying a 1363 socket in it, with a switchable 1Ω resistor in the cpc. That's for checking your loop tester - you can plug it in anywhere and do a test, doesn't matter what the reading is as long as it goes up by 1Ω when you switch the resistor in.

If you want you can put an RCD in the box as well for doing those checks using a non RCD socket at home, rather than annoying the cat by tripping yours.

Job's a good-un.

PS: This is the sort of item I've described, apart from the RCD

 

[ban-all-sheds]

I want to do the later which means i have to set up a home made circuit with which to test the device. (I think this is correct)

I have to say that if you need someone to tell you how to build one then you clearly don't actually understand what your tester does...

 

[Deleted member 26818]

I kind of understand what my tester does, but how it does it is another matter.
For instance, to test continuity or IR, I have to connect the N and the E probes together and then test between them and the L probe.
Yet when testing RCDs, or EFLI, the probes are connected separately to L,N&E.

 

[ban-all-sheds]

I kind of understand what my tester does, but how it does it is another matter.

My point is that if you know what it does then you must know what to put into a check box. If you don't know what to put into a check box then it's hard to see that you know what your tester is doing.

You may well know how to use it at a "put these probes there, turn that switch to there, press this button and write the number that appears in the display in this box on the schedule of results" level, but that's not understanding.

For instance, to test continuity or IR, I have to connect the N and the E probes together and then test between them and the L probe.

Really?

 

[Guest123]

For instance, to test continuity or IR, I have to connect the N and the E probes together and then test between them and the L probe.

Is it a Metrel Spin???