ITTSB.EU Blog Forum
Multimeter | Clamp meter | Insulation Resistance Tester | Panel Meter | Oscilloscopes | Test leads & Accessories | Software Updates => Handheld multimeter => Topic started by: Kiriakos GR on April 15, 2025, 05:04:20 PM
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I did engage today so to perform Calibration Adjustment, at my professional grade analogue multimeter.
My BBC GOERZ MA 4S, this has a lovely large and clean scale, but I have to admit that I got dizzy by looking for accurate readings on it needle. :)
I did go thru detailed inspection, Volts, mA, Ampere, AC & DC ranges, plus it two resistor ranges.
In total, I was perform measurements for about two hours, as I was checking also for best repeatability.
Due this opportunity I did my homework again of how to assist my self so to defeat Parallax Error.
Long story in sort, when you can see at the mirror within the scale the needle, this translates that your head this is not in perfect alignment with the needle.
Perfect alignment = the shadow of the needle, this does not appear, from neither of the sides, of the actual needle.
In my case, I was had daylight, this coming from the side of the meter, and this did my task more difficult.
For analog multimeter them be designed to operate as flat for best accuracy, the lighting at the working bench this must be centered too.
For decades, electronics service men, they has had to place their multimeter under an angle, so to regain convenience.
Easy to read multimeter screen, this is of high importance when you work all day long, by repairing things.
In summary: We never perform electrical measurements by looking the shadow of the needle.
The shadow of the needle, this is a warning that we are out of the target. :)
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Video footage aid. ;)
https://www.youtube.com/watch?v=P0n1u1JFK0g&t=5s (https://www.youtube.com/watch?v=P0n1u1JFK0g&t=5s)