WEBVTT

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To measure our very low safety voltage at I limited, I work under voltage

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This voltmeter automatically closes the terminals not to be used

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Better still to start from the voltmeter (no voltage, even SELV, in the hands)

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2.5 volts read, small inaccuracy of the voltmeter integrated in the generator

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This voltmeter being automatic, it switches its gauges when the voltage increases

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Avoid disconnecting the voltmeter side as a voltage is present!

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Here is how to do even in SELV limited in intensity: Good habit to take!

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The common and the terminal Volt. OK, but the caliber?

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If we do not know too much: we use the highest (1 000 V, which can + ...)

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Terminal Volt on the +, COM on the -

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On the 1 000 V caliber, the 1 of 1.23 V does not appear! The last digit is fancy :-)

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Analogy: the last digit: graduations of the rule, to +/- 1 near uncertain

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We are always between 2 values, so ...

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The last digit, specified on the manufacturer's documentation, is 'just' between + and - X

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From +/- 1 to +/- 4 digits! So the last figure, forget it a little :-)

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Here we display 4 for almost 6 Volts in reality ...

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It's already better with 2 significant digits!

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As seen, we use that the numbers on the left, the last 'for info'

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We will therefore take the caliber giving as many possible figures in volmeter

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The lower 2-volt gauge is not suitable

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Even if it is protected, do not leave your voltmeter in excess!

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If I invert, I get - 5.6 Volts

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This model is a 20,000 point, it offers 1 more figure!

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We can get 5 digits, so 4 exploitable!

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There are models of 40,000 points, but after that you have to take into account the temperature during the measurement, the resistance of wire and contact ...

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We will be content with 2 significant figures

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This model is a 6,000 points

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This True RMS model measures the alternate even NON-sinusoidal

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Bloopers: pronounce 'true' RMS difficult for french :-)