User manual

22 GMC-I Messtechnik GmbH

Control Functions

Example

The voltage measuring range is set manually to 30 V.

The first measured value is 5 V and is stored to memory because

it is greater than 10% of the measuring range (= 3 V), and is thus

reliable above the background noise level. As soon as the

measured values drops to less than 10% of the measuring range,

i.e. amounts to less than 3 V which corresponds to removal of the

test probes from the measuring point, the instrument is ready to

store a new value.

4.4.1 Function DATA during insulation measurement *

This DATA function differs from the standard DATA-Compare

function.

In the interference voltage measurement function V(ac+dc)1M

the special DATA function for insulation measurement is activated

by pressing the DATA key – DATA blinks in the display. During inter-

ference voltage measurement, no DATA values are determined or

stored yet. By briefly pressing the FUNC | ENTER key, the insulation

measurement is activated and the test voltage is applied. An inter-

mittent acoustic signal indicates to the user that the test voltage is

applied (accompanied by a blinking of the ISO symbol in the dis-

play). After applying the test probes, a check is being made as to

whether a valid measured value is present. As soon as a stable

measured value appears in the display, the DATA value is stored

(frozen in the display). A long acoustic signal indicates that the

measurement is completed, the test voltage is switched off again,

DATA no longer blinks and the user can read and note down the

measured value. By repeatedly pressing the FUNC | ENTER key, the

test voltage is applied again and DATA is activated (DATA blinks in

the display).

If no DATA value is determined or if OL is shown in the display, the

test voltage is automatically switched off after approx. 10 sec-

onds. In order to deactivate the DATA function, the FUNC | ENTER

key must be pressed and held.

* This function is especially available for variant METRAHIT ISO AERO,

for other variants as from firmware version 1.18.