30
GMC-I Messtechnik GmbH
6.6.4
Direct and Pulsating Voltage Measurement, V DC and
V (AC+DC)
➭
Set the rotary switch to V
or V .
➭
Press the
MENU
key.
➭
Press the “Setup for currently selected measurement” softkey.
➭
Make sure that the
Clip
parameter is set to
Off
. Otherwise all
measured values are displayed in amperes, corrected by the
amount resulting from the selected transformation ratio for an
interconnected current clamp sensor.
➭
The display is returned to the measurement view by pressing
the
ESC
key twice.
➭
Repeatedly press the
Func
softkey until the desired measuring
function is displayed.
➭
If necessary, conduct zero balancing by pressing the
Zero
key
(see description below).
➭
Connect the measurement cables as shown.
The “
” connector jack should be grounded.
➭
Measurement is started immediately.
Note
V (AC+DC) measurement:
Due to system design, the DC
component displayed in the smallest measuring range
(300 mV) has an offset. Select the VDC function for pre-
cise measurement of the DC component.
Note
An intermittent acoustic signal warns the operator if the
measured value exceeds the upper range limit in the
1000 V range.
Make sure that a current measuring range (“A”) has
not
been acti-
vated, when the multimeter is connected for voltage measure-
ment! If the fuse’s blowing limits are exceeded as a result of oper-
ator error, both the operator and the instrument are in danger!
As soon a the
Man / Auto
key is pressed, and assuming the mea-
sured value is less than 280 mV, the multimeter is switched to the
mV measuring range.
V (AC+DC) Fil – Measurement with Low-Pass filter
Attention!
!
Be aware of the fact that dangerous voltage spikes are
not displayed during this type of measurement (see also
“Voltage Comparator”).
We recommend measuring voltage without the low-pass
filter first, in order to be able to detect any dangerous
voltages.
A 1 kHz/-3dB low-pass filter can be activated if required, in order
to filter out capacitively induced high frequency pulses of greater
than 1 kHz, for example when performing measurements at
cables, i.e. undesired voltages of greater than 1 kHz can be sup-
pressed.
Fil
appears at the display in order to indicate the respectively acti-
vated low-pass filter. The multimeter is automatically switched to
manual measuring range selection.
Specified measuring accuracy is not reached with signals of
greater than 500 Hz when the filter is active.
Voltage Comparator for Displaying Dangerous Voltage
The input signal or measuring signal is checked by a voltage com-
parator for dangerous spikes, because these do not appear at the
display when the low-pass filter is used.
At voltages of greater than 15 V AC or 25 V DC, a danger symbol
appears at the display:
Improving Accuracy by means of Zero Balancing – Zero
The currently measured voltage value can be subtracted from
future measurements in all voltage measuring ranges.
➭
Press the
Zero
softkey.
➭
The value ascertained for
Zero
is saved and appears above the
measurement display. Automatic compensation is imple-
mented for future measurements. This value remains in mem-
ory even after the instrument has been switched off.
➭
The value for Zero is retained when the instrument is switched
to a different measuring function. The correction or offset value
is deleted by pressing
Zero
once again, or when the instrument
is switched off. The value is cleared from the display.
S–
A
V
Temp
m
/4
COIL
S+
V
V
300 mV/3 V/30 V
Measuring ranges:
– (+)
+ (–)
300 V/1000 V
Func
Func
Func
Max. 1000 V 3 kHz
P
max
= 3 x 10
6
V x Hz
VDC
V AC/DC
V (AC+DC) Fil
Zero
Zero
Zero
