Can an ESD mat be tested without special tools?

I do not test anti-static mats, but do test insulating mats for when we do silly things like working on live apparatus, but I am looking for higher resistances than those expected for an ESD mat.

The ESD mat will discharge the static voltage fairly slowly to prevent the user from feeling the shock, ESD clothing will also to that, but are also worn to prevent the build up to a degree. shabaz, yes antistatic clothing will have a micro fine grid woven throughout the fabric which is conductive. There is usually a couple of areas in the garment where the connection is made to the grid, as the grid has to touch the skin to be effective. You will see it more if you can look at a antistatic hi-vis coat, the grid will be very obvious then.

It looks like the standard for ESD mats uses two test voltages, 10V and 100V. There are plenty of insulation testers that will have a 100V setting, a 10V setting is not so common and I suspect you would be looking at a quite expensive insulation tester aimed at the communications market, probably with a variable voltage function. You also need to read their specification carefully, as a lot of them will have a reduced resistance measurement at a lower test voltage, for the U1461AU1461A, that is 66 GOhms at 100V. Probably adequate for this application, but a cheaper insulation tester may only measure up to 100 MOhms with a 100V test voltage.

As Gough Lui as mentioned, they have a current limit, usually in the region of 1.5mA to 2mA for a handheld 'multimeter' style tester. Whilst this may make you jump, it isn't enough to kill, even on a 1000V test, so they are reasonably safe in the hands of a responsible person. There are two caveats to this, if you zap yourself with the insulation tester when on a ladder or in an unbalanced situation etc, the resulting fall could hurt you, secondly, and aimed at the timed tests, if you charge something up with the insulation tester, that apparatus can then hold that charge for a long while, and discharge it with a much higher current flow. That will hurt considerably more, and in some circumstances have the potential to be fatal. For this reason, the insulation tester should discharge the circuit itself after the test, but not all of them do, or do so very slowly.

Timed tests are only carried out on insulation systems that show a polarising affect, I doubt an ESD mat can be polarised, to it is probably a short duration test, something like 10 seconds.

The problem with measuring high resistances is that they are very prone to errors introduced by the setup, but these tend to result in a lower value rather than a high value.

The tester doesn't measure resistance directly, it calculates it from applying a known voltage and measuring the resultant current. But at 100V and 100s of megohms, the current will be low and very susceptible to noise. It is also susceptible to leakage currents from the test leads and even yourself if you are holding the probes during the test.

It looks like a lot of the ESD testers for shop use, seem to work on an LED go / no-go indication. You may be able to set up such a system with your power supply and a amplifier / comparator circuit comparing the voltage across a shunt, against a calibrated setting based upon the acceptable values in the standard. That may be cheaper than purchasing an insulation tester with the right capability.

If you have access to an electrometer or source measurement unit, they usually have the right voltage ranges and can measure very high resistance values, but again are ridiculously expensive to purchase - unless you can persuade rscasny to do some road tests on ESD testers, insulation testers, or source measurement units!

Kind regards.

I do not test anti-static mats, but do test insulating mats for when we do silly things like working on live apparatus, but I am looking for higher resistances than those expected for an ESD mat.

The ESD mat will discharge the static voltage fairly slowly to prevent the user from feeling the shock, ESD clothing will also to that, but are also worn to prevent the build up to a degree. shabaz, yes antistatic clothing will have a micro fine grid woven throughout the fabric which is conductive. There is usually a couple of areas in the garment where the connection is made to the grid, as the grid has to touch the skin to be effective. You will see it more if you can look at a antistatic hi-vis coat, the grid will be very obvious then.

It looks like the standard for ESD mats uses two test voltages, 10V and 100V. There are plenty of insulation testers that will have a 100V setting, a 10V setting is not so common and I suspect you would be looking at a quite expensive insulation tester aimed at the communications market, probably with a variable voltage function. You also need to read their specification carefully, as a lot of them will have a reduced resistance measurement at a lower test voltage, for the U1461AU1461A, that is 66 GOhms at 100V. Probably adequate for this application, but a cheaper insulation tester may only measure up to 100 MOhms with a 100V test voltage.

As Gough Lui as mentioned, they have a current limit, usually in the region of 1.5mA to 2mA for a handheld 'multimeter' style tester. Whilst this may make you jump, it isn't enough to kill, even on a 1000V test, so they are reasonably safe in the hands of a responsible person. There are two caveats to this, if you zap yourself with the insulation tester when on a ladder or in an unbalanced situation etc, the resulting fall could hurt you, secondly, and aimed at the timed tests, if you charge something up with the insulation tester, that apparatus can then hold that charge for a long while, and discharge it with a much higher current flow. That will hurt considerably more, and in some circumstances have the potential to be fatal. For this reason, the insulation tester should discharge the circuit itself after the test, but not all of them do, or do so very slowly.

Timed tests are only carried out on insulation systems that show a polarising affect, I doubt an ESD mat can be polarised, to it is probably a short duration test, something like 10 seconds.

The problem with measuring high resistances is that they are very prone to errors introduced by the setup, but these tend to result in a lower value rather than a high value.

The tester doesn't measure resistance directly, it calculates it from applying a known voltage and measuring the resultant current. But at 100V and 100s of megohms, the current will be low and very susceptible to noise. It is also susceptible to leakage currents from the test leads and even yourself if you are holding the probes during the test.

It looks like a lot of the ESD testers for shop use, seem to work on an LED go / no-go indication. You may be able to set up such a system with your power supply and a amplifier / comparator circuit comparing the voltage across a shunt, against a calibrated setting based upon the acceptable values in the standard. That may be cheaper than purchasing an insulation tester with the right capability.

If you have access to an electrometer or source measurement unit, they usually have the right voltage ranges and can measure very high resistance values, but again are ridiculously expensive to purchase - unless you can persuade rscasny to do some road tests on ESD testers, insulation testers, or source measurement units!

Kind regards.