# Fluke Meter

##### Senior Member
Hi Guys,
How does a Fluke meter work when measuring insulation resistance? Does it apply a certain test voltage and measure the return current to calculate the resultant resistance value? Looking through the Fluke 1587 specs, I see that "output" voltage on the meter is up to 1000Volts. How can that be? The Fluke meter uses (4) AA type batteries - how can it generate such a high voltage? Would 1000V be the maximum voltage that the meter is designed to measure?

#### tom baker

##### First Chief Moderator
Staff member
I didnt trust that type of fluke insulation tester over using a hand crank meager. But once I used the fluke, and it was a DVM as well, the meager was put on the shelf
How does it work? Likely a dc to dc converter.

#### gar

##### Senior Member
220920-2233 edt

It is simply a result of v = K*N* dPhi/dt.

How does a typical automotive ignition system work? I would think that electricians would be taught some of these basics.

.

#### tortuga

##### Code Historian
I would think that electricians would be taught some of these basics.
Sorry were not, and if we were we forgot care to give us a refresher ?

#### gar

##### Senior Member
220920-2354 EDT

I should also point out that a simple transformer without inductive kick is a useful way to increase voltage.

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#### zbang

##### Senior Member
How does a Fluke meter work when measuring insulation resistance? Does it apply a certain test voltage and measure the return current to calculate the resultant resistance value? Looking through the Fluke 1587 specs, I see that "output" voltage on the meter is up to 1000Volts. How can that be? The Fluke meter uses (4) AA type batteries - how can it generate such a high voltage? Would 1000V be the maximum voltage that the meter is designed to measure?
Quite well.
Yes.
A voltage multiplier.
The same voltage multiplier.
Probably, but an insulation tester isn't measuring voltage, it's measuring current (question #2).

Fluke probably has a white paper or something that explains things.

#### Frank DuVal

##### Senior Member
Um, a transformer is not taught? Convert the DC to AC with a switching circuit (like points in old cars did), feed the primary of a step up transformer, use high voltage coming out of secondary. Lesson over.

#### tortuga

##### Code Historian
220920-2233 edt

It is simply a result of v = K*N* dPhi/dt.

How does a typical automotive ignition system work? I would think that electricians would be taught some of these basics.

.

#### garbo

##### Senior Member
Hi Guys,
How does a Fluke meter work when measuring insulation resistance? Does it apply a certain test voltage and measure the return current to calculate the resultant resistance value? Looking through the Fluke 1587 specs, I see that "output" voltage on the meter is up to 1000Volts. How can that be? The Fluke meter uses (4) AA type batteries - how can it generate such a high voltage? Would 1000V be the maximum voltage that the meter is designed to measure?