Function
20
IRDH575_D00089_05_M_XXEN/01.2020
R1/R2 bridged + Memory: on fault memory activated
R1/R2 bridged + Memory: off fault memory activated
R1/R2 not connected + Memory: on fault memory activated
R1/R2 not connected + Memory: off fault memory deactivated
*) measuring principle "adaptive measuring pulse", a measuring
principle developed by Bender.
3.5.1 Current output for external measuring instrument
The current output of IRDH575 provides 0(4)…20 mA. The current output is
electrically isolated from the device electronics and the RS-485 interface. The
ISO SETUP menu, on page 54, allows to switch over between 0…20 mA and
4…20 mA.
3.5.2 Real-time clock
The real-time clock serves as a time base for the historical memory and self
test function. At first the correct time and date must be set in the menu
"ISO ADVANCED". 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 thirty days. If the 24 h self test is activated in the ISO ADVANCED me-
nu, a special time of day can be selected for the execution of the self test in the
menu "TEST: 12:00". 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.
3.5.3 Insulation fault location
Another function of the IRDH575 is selective insulation fault location. If the va-
lue of the insulation resistance falls below the set response values ALARM 1
and ALARM 2, a certain test current is generated by the IRDH575. The maxi-
mum value of the test current is determined by the maxPuls parameter, see
page 60. In combination with an insulation fault evaluator EDS47…and the
associated measuring current transformers connected to it, the insulation
fault is selectively detected. The detected insulation fault is signalled to the
To Next Page
Loading...
Need help?
General
