Bender B91016330, Руководство пользователя

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Device description
14 isoGEN523_D00320_04_M_XXEN/06.2018
3.2.5 Monitoring the insulation resistance
The two parameters "R1" and "R2" monitor the insulation resistance. The value R1 can
only be set higher than the value R2. If the insulation resistance
R
F
reaches or falls below
the activated values R1 or R2, then this leads to an alarm message. If R
F
exceeds the val-
ues R1 or R2 plus the hysteresis value (see table on page 23 ), the alarm will be cleared.
3.2.6 Undervoltage/overvoltage monitoring
The two parameters "U <" and "U >" can be activated or deactivated for monitoring the
nominal system voltage
U
n
. The maximum undervoltage value is limited by the over-
voltage value. The RMS value of the system voltage is monitored. If the nominal system
voltage
U
n
reaches, falls below or exceeds the limit values ("U <" or "U >"), an alarm will
be signalled. If the maximum permissible system voltage set for the ISOMETER® is ex-
ceeded, an alarm will be triggered even if the overvoltage limit value has been deacti-
vated. The alarm will be deleted when the limit values plus hysteresis are no longer
violated.
3.2.7 Self test/Device fault
The integrated self test function checks the function of the insulation monitoring de-
vice and the connection to earth and to the IT system to be monitored. By pressing the
external test/reset button a self test is started. In the event of a fault, relay 2 ("K2")
switches and the measuring function is interrupted. Internal device errors can be
caused by external disturbances or internal hardware errors. After eliminating the fault,
the alarm relays switch back automatically or by pressing the external T/R button (see
page 16) . The self test can take up to 30 s.
It can be suppressed for the duration of the device start by setting the parameter in the
menu "SEt" to"S.Ct = off" (i.e. device test after device start = off). This allows the ISOME-
TER® to enter measurement mode quickly after connecting the supply voltage
U
s
.
If the error message occurs again after restarting the device or after a reset to factory
settings, the device must be repaired.
Automatic self test
The device runs a self test after connecting to the supply voltage U
s
and then every
24 h.