12
GMC-I Gossen-Metrawatt GmbH
7.3
Transient Overvoltages
The METRA HIT 16 I/L and T multimeters are protected against
transient overvoltages of up to 6 kV with a rise time of 1.2 and a
decay time of 50
μ
s. Due to the fact that overvoltages of greater
duration can be expected when performing measurements, for
example in power supply networks or at transformers and motors,
we recommend our KS30 measuring adapter for such cases. It
provides for protection against transient overvoltages of up to 6 kV
with a rise time of 10 and a decay time of 1000
μ
s. Continuous
loading capability is equal to 1200 V
eff
.
When using the measuring adapter KS30 the additional measure-
ment is about approx. –2 %.
7.4
Measurement of Voltages Greater than 600 V
Voltages of greater than 600 V can be measured with a
high-voltage probe, e.g. HV3 or HV30 from GMC-I Gossen-Metra-
watt GmbH. The bonding terminal must be grounded for measure-
ments of this type, and all required safety precautions must be
observed!
7.5
Duty Cycle Measurement only with METRA HIT 16L
With a duty cycle measurement, you can determine the ratio of
pulse duration to cycle time of regularly recurring square-wave sig-
nals.
➭
Set the function selector switch to
V
/Hz/%
or
V~/Hz/%
.
➭
Connections are made in the same way as for voltage measure-
ment.
➭
Briefly press the yellow multi-function pushbutton twice. The
meter switches to duty cycle measurement. The duty cycle – that
is the percentage pulse duration of a signal – is displayed on the
LCD in %.
Notes
The applied frequency must remain constant during the duty cycle
measurement.
Repeated brief pressing of the multifunction key
FUNC
changes the
measuring functions in the following order: Voltage
→
frequency
→
duty cycle
→
voltage
→
…
.
600V
V
F
°
C
V
1M
M
1000V=ISO
METRA
HIT
16I/L
blac
k
re
d
x1000
x100
Measurement of Voltages
greater than 600 V
with the HV3 High-Voltage
Probe
black
Duty cycle (%) = ——————— • 100
Pulse duration
Cycle duration
