This measuring principle allows for the precise monitoring of modern power supply
systems, pure DC systems, systems where AC/DC rectification and power conversion may occur,
systems with variable frequency drives (VFDs), and systems with high leakage capacitances.
1 - External supply voltage used to power device
2 - Wiring diagram for a three-phase system. Only two connections
to the system are necessary to monitor all three phases.
3 Wiring diagram for a single-phase system
4 - Wiring diagram for a DC system
5 - Equipment ground connections
6 - External test button (normally open contact)
7 - External reset button (normally closed contact). When the
terminals are open, the fault message will not be stored.
8 - Standby contact. When the contact is closed, no insulation
measurements take place.
9 - IRDH275: Analog output, electrically isolated: 0 - 400 µA
IRDH275B: Analog output, electrically isolated:
0 - 20 mA or 4 - 20 mA
10 - RS-485 interface:
IRDH275: One-way ASCII stream with measurement status
IRDH275B: Two-way communication with other BENDER
devices, including communication gateways
11 - Alarm relay 1, normally energized or de energized contact
12 - Alarm relay 2/System Fault Relay, normally energized or deenergized
contact
1 - INFO key: displays pertinent system information
ESC key: Goes back a step inside device's menu
2 - TEST button: Activates self-test
Arrow up key: Scrolls up inside device's menu
3 - LCD display
4 - RESET button: Resets device
Arrow down key: Scrolls down inside device's menu
5 - MENU key: Activates device's internal menu
Enter key: Confirm change inside device's menu
6 - Alarm LED 1 lights: Alarm, Prealarm
7 - Alarm LED 2 lights: Alarm, Main alarm
8 - System fault LED: Lights on connection or device error
