janitza UMG 604, Operating Manual

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30
UMG 604
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Important!
The voltage measurement inputs are
hazardous live!
Important!
The UMG604 can only determine
measured values if a measurement-
current voltage greater than 10 Veff
is applied to at least one voltage
measurement input.
Voltage measurement
The UMG604 is designed for the measurement
of alternating voltages in 300 V systems in
which category III overvoltages can occur.
The UMG604 can only determine measured
values if a measurement-current voltage
greater than 10 Veff is applied to at least one
voltage measurement input.
The following must be noted when selecting
the instrument leads for the voltage
measurement:
• The instrument leads required for the
voltage measurement must be suitable
for voltages up to 300 VAC to earth and
520 VAC conductor to conductor.
• Normal instrument leads must be fused by
an overcurrent protective device and routed
via disconnectors.
• Short-circuit proof instrument leads must be
routed via disconnectors only.
Overcurrent protective devices and
disconnectors must be positioned near the
device and must be easy for the user to
reach.
Fig. 30.1 Connection example: Voltage measure-
ment via short-circuit proof instrument leads.
Disconnector
L3
N
L1
L2
10A
(UL listed)
For the inputs L4 and I4 are no con-
nection schemes required.
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