Safety Information; Functional Description - Bender ISOMETER isoES425 Kurzanleitung

2. Safety information

Installation, connection and commissioning of electrical equipment shall only
be carried out by qualified electricians. Particular attention must be paid to:
The current safety regulations, in particular DIN EN 50110
 
Enclosed sheet "Important safety instructions for Bender Products".
 

3. Functional description

The ISOMETER® measures the unsymmetrical insulation resistance R
ween the network being monitored (L1/+, L2/-) and earth (PE). The effective
value of the nominal system voltage U
residual voltages U
and earth) are also measured. The ISOMETER® determines the faulty conduc-
tor L1/+/L2/- from a minimum value of the nominal system voltage, i.e. the
distribution of the insulation resistance between the L1/+ and L2/- conduc-
tors, and, depending on where the fault is, adds a positive or negative sign to
the insulation resistance measurement. The value range of the faulty conduc-
tor is ±100 %. In an AC system, the location of the fault in an intermediate DC
circuit is determined from a minimum value of the nominal system voltage
between the AC system and earth and is identified by a positive or negative
sign positioned before the insulation resistance measurement. A percentage
distribution to determine the location of the fault is not possible. Therefore,
the faulty conductor "R%" is only represented as a one-sided error on L1/+ (i.e.
+100%) or L2/- (i.e. -100%).
The detected fault or the conductor with the fault can be assigned, via the me-
nu, to an alarm relay. If the values of R
"AL" menu, this will be indicated by the LEDs, and relays "K1" and "K2" accor-
ding to the message assignment settings in the "out" menu. In addition, the
operation of the relay (n.o./n.c) can be set and the fault memory "M" activated.
isoES425_D00214_00_Q_DEEN/08.2017
If the ISOMETER® is installed inside a control cabinet, the
insulation fault message must be audible and/or visible to
attract attention.
(between L1/+ and earth) and U
L1/+e
between L1/+ and L2/- as well as the
n
or U exceed the thresholds set in the
F n
bet-
F
(between L2/-
L2/-e
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