Function
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isoLR275_D00127_00_M_XXEN/07.2018
2.4.4
Real-time clock
The real-time clock serves as a time base for the memory and self test func-
tions. First, the correct time and date must be set in the "ISO ADVANCED“ me-
nu. If time and date are not set, a "C“ (clock) is flashing in the standard display.
In the event of a supply voltage failure, time and date will be stored for at least
30 days.
When the 24 h self test is activated in the ISO ADVANCED menu, it is possible
to set the time (hour) for carrying out the self test by means of the
"TEST: 12:00" menu. Then a self test will be started automatically once a day
exactly at the preset time. If the 1 h test has been selected, the self test is au-
tomatically carried out every full hour.
2.4.5
Coupled IT systems
When using ISOMETER®s in IT systems, make sure that only one active
ISOMETER® is connected in each interconnected system. If IT systems are in-
terconnected via coupling switches, make sure that ISOMETER®s not currently
used are disconnected from the IT system and deactivated. IT systems coup-
led via diodes or capacitances may also influence the insulation monitoring
process so that a central control of the different ISOMETER®s is required.
