Bender ISOMETER IRDH575, Руководство пользователя

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Operation and setting
61
IRDH575_D00089_05_M_XXEN/01.2020
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10, 25 and 50 mA for EDS470 / 460 / 490 systems, preferably 25 mA.
10 mA is recommended when sensitive equipment such as control
relays is supplied by the system. 50 mA should only be used in case of
systems involving a lot of parallel faults (factory setting 25 mA).
The test current of the IRDH575 is factory set to 25 mA.
Resulting from the type of supply system, the real test current in AC systems
is lower than the setting. The reduction factor is 0.5 in AC-Systems and 0.67 in
3AC systems. Therefore, the test current setting 1 mA for EDS473 and 10 mA
for EDS470 devices is not admissible in AC systems.
A list of possible test current settings for IRDH575 in relation to the type of
supply system and insulation fault evaluators is given in the table below:
Do not use these settings for supply voltages > 575 V.
Otherwise test currents up to 7 mA can occur, which can
damage sensitive equipment.
Please note that the test current is to be set according to the
type of supply system.
Type of supply
system
EDS460/490
min. max.
EDS461/491
min. max.
DC
AC
3AC
10 mA 50 mA
10 mA* 50 mA
10 mA* 50 mA 1 mA 2.5 mA
1 mA** 2.5 mA
1 mA** 2.5 mA