Bender ISOMETER isoMIL685W-D-P User manual

Manual
EN
isoMIL685W-D-P_D00263_04_M_XXEN/03.2021
ISOMETER®
isoMIL685W–D–P
Insulation Monitoring Device
with integrated locating current injector
for IT AC systems with galvanically connected
rectifiers and inverters and for IT DC systems
Software version: D440 V 1.28

Bender GmbH & Co. KG
P.O. Box 1161 • 35301 Grünberg • Germany
Londorfer Straße 65 • 35305 Grünberg • Germany
Tel.: [phone]
Fax: [phone]
Email: [e-mail]
Web: www.bender.de
© Bender GmbH & Co. KG
All rights reserved.
Reproduction only with permission
of the publisher.
Subject to change.
Customer service:
Service hotline: 0700-BenderHelp (Telephone and Fax)
Carl-Benz-Straße 8 • 35305 Grünberg • Germany
Tel.:[phone]
Fax:[phone]
Email:[email protected]
PLEASE READ THIS MANUAL AND ANY ACCOMPANYING DOCUMENTS CAREFULLY
AND KEEP THEM IN A SECURE PLACE FOR FUTURE REFERENCE.

Table of contents
3isoMIL685D-D-P_D00263_04_M_XXEN/03.2021
1. Important information ................................................................................7
1.1 How to use this manual. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
1.2 Technical support . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
1.2.1 End customer support and advice . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
1.2.2 Repair . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
1.2.3 Customer service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
1.3 Training courses. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
1.4 Delivery conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
1.5 Storage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
1.6 Warranty and liability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
1.7 Disposal. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
2. Safety instructions .......................................................................................9
2.1 General safety instructions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
2.2 Work activities on electrical installations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
2.3 Device-specific safety information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
2.4 Intended use . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
3. Function .......................................................................................................10
3.1 Features. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
3.1.1 Features EDS44x . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
3.2 Product description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
3.3 Function description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
3.4 Insulation fault location. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
3.4.1 Compatibility with EDS-devices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12
3.5 Interfaces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
3.6 Self test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
4. Device overview .........................................................................................13
4.1 Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
4.2 Device variants . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
4.3 Connection and panel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
4.4 Display elements and device buttons . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
4.4.1 Display elements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
4.4.2 device buttons . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
4.5 Operating and navigating . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
4.5.1 Menu selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16
4.5.2 List selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16
4.5.3 Parameter selection and value adjustment . . . . . . . . . . . . . . . . . . . . . . . . .16
4.5.4 Character input . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16
4.5.5 Multiple selection in the device menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16
5. Mounting ..................................................................................................... 17
5.1 Common information. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17
5.2 Mounting spaces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17
5.3 Screw mounting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18
5.4 DIN rail mounting. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18
6. Connection .................................................................................................. 19
6.1 Connection conditions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19
6.2 Connection to a 3(N)AC system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20
6.3 Connection to an AC system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20
6.4 Connection to a DC system. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21
6.5 Connection to the supply voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21
6.6 Connection to the X1 interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22
6.7 Connection to the Ethernet interface ETH. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22
6.8 Connection of the relay interfaces 1 and 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22
6.9 Terminal covers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23
6.10 Connection to the BB bus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23
6.11 Connection of EDS44x/IOM441 to the ISOMETER® . . . . . . . . . . . . . . . . . . . .24
6.11.1 Connection example ISOMETER® to EDS . . . . . . . . . . . . . . . . . . . . . . . . . . .25
6.11.2 Connection to a 3(N)AC system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .26
6.11.3 Connection to an AC system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .27
6.11.4 Connection to a DC system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .28
6.11.5 System structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .29
7. Commissioning .......................................................................................... 30
7.1 General initial commissioning process. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .30
7.2 Initial commissioning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31
7.2.1 Setting language . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31
7.2.2 Setting date and time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31
7.2.3 Setting system type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31
7.2.4 Setting profile . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31
7.2.5 Setting EDS mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31
7.2.6 Setting EDS current . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .32
7.2.7 Setting response value Ran1 for alarm 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . .32
7.2.8 Setting response value Ran2 for alarm 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . .32
7.3 Commissioning of EDS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .32
7.4 Recommissioning. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33
7.5 Configuring password protection for the ISOMETER® iso685. . . . . . . . . . . .33

Table of contents
4isoMIL685D-D-P_D00263_04_M_XXEN/03.2021
8. Display ..........................................................................................................34
8.1 Standard display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .34
8.2 Fault display (active). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
8.3 Fault display (inactive) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
8.4 Acknowledging a fault message . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
8.5 Data-isoGraph. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
8.6 History memory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .36
8.7 ISOnet operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .36
8.8 ISOloop operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
8.9 Automatic test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
8.10 Insulation fault location . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
9. Settings ........................................................................................................38
9.1 Menustructure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .38
9.2 Settings in the device menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
9.2 (1.0) Alarm settings 39
9.2 (1.1) Insulation alarm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
9.2 (1.1.1) Alarm 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
9.2 (1.1.2) Alarm 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
9.2 (1.1.3) Fault memory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
9.2 (1.2) DC alarm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
9.2 (1.2.1) Alarm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
9.2 (1.2.2) U(DC-E) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
9.2 (1.3) Profile . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
9.2 (1.4) System type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
9.2 (1.5) ISOnet. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
9.2 (1.5.1) ISOnet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
9.2 (1.5.2) Number of devices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
9.2 (1.6) ISOloop . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
9.2 (1.6.1) ISOloop . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
9.2 (1.6.2) Measured value subscription . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
9.2 (1.7) (Start) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
9.2 (1.8) Coupling monitoring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
9.2 (1.9) Behaviour when inactive . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
9.2 (1.10) Inputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
9.2 (1.10.1) Digital 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
9.2 (1.10.2) Digital 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
9.2 (1.10.3) Digital 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
9.2 (1.11) Outputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
9.2 (1.11.1) Relay 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
9.2 (1.11.2) Relais 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
9.2 (1.11.3) Digital 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
9.2 (1.11.4) Digital 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
9.2 (1.11.5) Buzzer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
9.2 (1.11.6) Analogue . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
9.2 (2.0) EDS (insulation fault location) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
9.2 (2.1) General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
9.2 (2.1.1) Current. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
9.2 (2.1.2) Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
9.2 (2.1.3) Using a portable EDS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
9.2 (2.1.4) EDSsync. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
9.2 (2.1.5) Scan for channels: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
9.2 (2.2) Scanning channels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
9.2 (2.3) Activating channels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
9.2 (2.4) Group settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
9.2 (2.4.1) Channel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
9.2 (2.4.2) Outputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
9.2 (2.4.3) Dig. input . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
9.2 (2.4.4) Device settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
9.2 (2.5) Channel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
9.2 (2.5.1) Name . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
9.2 (2.5.2) CT monitoring. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
9.2 (2.5.3) Response value I∆L . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
9.2 (2.5.4) Response value I∆n . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
9.2 (2.6) Outputs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
9.2 (2.6.1) Common relays. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
9.2 (2.6.2) Channel relays. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
9.2 (2.6.3) Buzzer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
9.2 (2.6.4) Digital output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
9.2 (2.7) Inputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
9.2 (2.7.1) Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
9.2 (2.7.2) t(on) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
9.2 (2.7.3) t(off) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
9.2 (2.7.4) Function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
9.2 (2.8) Device . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
9.2 (2.8.1) Trigger . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
9.2 (2.8.2) Fault memory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
9.2 (2.9) Service. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
9.2 (3.0) Data measured values . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52

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5isoMIL685D-D-P_D00263_04_M_XXEN/03.2021
9.2 (4.0) Control. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
9.2 (4.1) TEST. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
9.2 (4.2) Reset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
9.2 (4.3) Start initial measurement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
9.2 (4.4) EDS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
9.2 (4.5) Device: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
9.2 (4.6) ISOnet priority . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
9.2 (5.0) History . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
9.2 (6.0) Device settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
9.2 (6.1) Language . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
9.2 (6.2) Clock . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
9.2 (6.2.1) Time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
9.2 (6.2.2) Format (time) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
9.2 (6.2.3) Summer time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
9.2 (6.2.4) Date . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
9.2 (6.2.5) Format (date) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
9.2 (6.2.6) NTP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
9.2 (6.2.7) NTP server . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
9.2 (6.2.8) UTC. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
9.2 (6.3) Interface. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
9.2 (6.3.1) Write access. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
9.2 (6.3.2) Ethernet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
9.2 (6.3.3) BCOM. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54
9.2 (6.3.4) Modbus/TCP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54
9.2 (6.3.5) RS-485 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54
9.2 (6.3.6) Modbus RTU . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54
9.2 (6.4) Display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54
9.2 (6.4.1) Brightness . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54
9.2 (6.4.2) Automatic dimming. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
9.2 (6.5) Password . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
9.2 (6.5.1) Password . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
9.2 (6.5.2) Status. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
9.2 (6.6) Commissioning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
9.2 (6.7) Data backup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
9.2 (6.8) Activation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
9.2 (6.9) Factory settings. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
9.2 (6.10) Software . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
9.2 (6.10.1) Update via interface. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
9.2 (6.10.2) Update . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
9.2 (6.11) Service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
9.2 (7.0) Info . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
10. Device communication ........................................................................... 56
10.1 Ethernet interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .56
10.2 BCOM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .56
10.3 Modbus/TCP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .56
10.4 Web server . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .56
10.4.1 Conventions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .56
10.4.2 Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .56
10.4.3 User interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .57
10.4.4 Menu structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .57
10.4.5 Parameter changes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .58
10.4.6 Changing parameters in the web browser . . . . . . . . . . . . . . . . . . . . . . . . .59
10.4.7 Changing parameters in the device menu when the
web browser is open . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .59
10.4.8 Write access for parameter changes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .59
10.5 BS bus. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .60
10.5.1 Master-slave principle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .60
10.5.2 Addresses and address ranges on the BS bus . . . . . . . . . . . . . . . . . . . . . . .60
10.5.3 RS-485 specifications/cables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .60
10.5.4 Cable routing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .60
10.6 Modbus RTU . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .60
10.7 isoData protocol. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .61
10.7.1 isoData-protocol table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .62
11. Insulation fault location ......................................................................... 65
11.1 General description. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .65
11.2 Required settings for insulation fault location . . . . . . . . . . . . . . . . . . . . . . . .65
11.3 Indication on the display. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .65
11.4 Starting and stopping the insulation fault location. . . . . . . . . . . . . . . . . . . .65
12. Special functions for coupled IT systems ............................................66
12.1 Particularities when monitoring coupled IT systems . . . . . . . . . . . . . . . . . .66
12.2 System isolation via digital input
with two coupled systems. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .66
12.3 System isolation via ISOnet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .67
12.3.1 Systempictures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .67
12.3.2 Configuration and function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .68
12.3.3 ISOnet priority . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .68
12.4 ISOloop . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .68
12.4.1 Preparing the devices in an interconnection . . . . . . . . . . . . . . . . . . . . . . .69
12.4.2 Creating groups with the BCOM Group Manager . . . . . . . . . . . . . . . . . . .69
12.4.3 Configuration and function on the ISOMETER® . . . . . . . . . . . . . . . . . . . . .71

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6isoMIL685D-D-P_D00263_04_M_XXEN/03.2021
12.5 EDSsync . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71
12.5.1 Preparing the devices in an interconnection . . . . . . . . . . . . . . . . . . . . . . .72
12.5.2 Creating groups with the BCOM Group Manager . . . . . . . . . . . . . . . . . . .72
12.5.3 Activating the function on the ISOMETER® . . . . . . . . . . . . . . . . . . . . . . . . . 73
13. Alarm messages .......................................................................................74
13.1 Measured value alarms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74
13.2 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74
13.3 ISOnet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75
13.4 ISOloop . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76
13.5 EDS44x alarm messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76
13.6 EDSsync . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77
14. Technical data ...........................................................................................78
14.1 Device profiles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78
14.2 Diagrams . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79
14.2.1 Response time profile power circuits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .79
14.2.2 Response time control circuits profile . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79
14.2.3 Response time generator profile . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .79
14.2.4 Response time high capacitance profile . . . . . . . . . . . . . . . . . . . . . . . . . . .79
14.2.5 Response time inverter > 10 Hz profile . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80
14.2.6 Response time inverter < 10 Hz profile . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80
14.2.7 Response time DC alarm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .80
14.2.8 Relative uncertainty . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .80
14.3 Factory settings isoMIL685W-D-P . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81
14.4 Tabular data isoMIL685W-D-P . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82
14.5 Standards and certifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84
14.6 Ordering details . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .85
14.6.1 Device . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .85
14.6.2 Accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .85
14.6.3 Insulation fault locator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .85
14.6.4 Suitable system components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .85
15. Glossary .....................................................................................................86
15.1 Document revision history. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86

isoMIL685D-D-P_D00263_04_M_XXEN/03.2021
7
Important information
1. Important information
1.1 How to use this manual
To make it easier for you to understand and revisit certain sections in this manual, we
have used symbols to identify important instructions and information. The meaning of
these symbols is explained below.
This manual is intended for qualified personnel working in electrical
engineering and electronics!
Read the manual before you begin to mount, connect, and commission
the unit. Always keep the manual within easy reach for future reference
following commissioning.
DANGER
This signal word indicates that there is a high risk of danger that will re-
sult in electrocution or serious injury if not avoided.
WARNING
This signal word indicates a medium risk of danger that can lead to
death or serious injury if not avoided.
CAUTION
This signal word indicates a low-level risk that can result in minor or
moderate injury or damage to property if not avoided.
This symbol denotes information intended to assist the user in making
optimum use of the product.
1.2 Technical support
1.2.1 End customer support and advice
Technical support by phone or e-mail for all Bender products
• Questions concerning specific customer applications
• Commissioning
• Troubleshooting
Telephone: [phone] (365 Tage von 07:00 - 20:00 Uhr [MEZ/UTC +1])
Fax: [phone]
0700BenderHelp (Tel. and Fax in Germany only)
E-mail: [email protected]
1.2.2 Repair
Repair, calibration, update and replacement service for Bender products
• Repairing, calibrating, testing and analysing Bender products
• Hardware and software update for Bender devices
• Delivery of replacement devices
• Extended guarantee, in-house repair service, replacement devices at no extra cost
Telephone: [phone]* (technical issues)
[phone]*, -785* (sales)
Fax: [phone]
E-mail: [email protected]
Please send the devices for repair to the following address:
Bender GmbH, Repair-Service,
Londorfer Straße 65,
35305 Grünberg
1.2.3 Customer service
On-site service for all Bender products
• Commissioning, parameter setting, maintenance, troubleshooting
• Analysis of the electrical installation in the building (power quality test, EMC test,
thermography)
• Training courses for customers
Telephone: [phone]*, -762* (technical issues)/
[phone]* (sales)
Fax: [phone]
E-mail: [email protected]
Internet: www.bender.de
* Mo-Thu 07:00 a.m. - 16:00 p.m. , Fr 07:00 a.m. - 13:00 p.m.

Important informationImportant information
isoMIL685D-D-P_D00263_04_M_XXEN/03.2021
8
1.3 Training courses
Bender is happy to provide training regarding the use of test equipment.
The dates of training courses and workshops can be found on the Internet at
www.bender-de.com -> Know-how -> Seminars.
1.4 Delivery conditions
Bender sale and delivery conditions apply.
For software products, the "Softwareklausel zur Überlassung von Standard-Software als
Teil von Lieferungen, Ergänzung und Änderung der Allgemeinen Lieferbedingungen für
Erzeugnisse und Leistungen der Elektroindustrie" (software clause in respect of the li-
censing of standard software as part of deliveries, modifications and changes to general
delivery conditions for products and services in the electrical industry) set out by the ZVEI
(Zentralverband Elektrotechnik- und Elektronikindustrie e.V.) (German Electrical and
Electronic Manufacturers' Association) also applies. Amending the “General Conditions
for the supply of Products and Services of the Electrical and Electronics Industry” (GL)*
Sale and delivery conditions can be obtained from Bender in printed or electronic format.
1.5 Storage
The devices must only be stored in areas where they are protected from dust, damp, and
spray and dripping water, and in which the specified storage temperatures can be
ensured.
1.6 Warranty and liability
Warranty and liability claims in the event of injury to persons or damage to property are
excluded if they can be attributed to one or more of the following causes:
• Improper use of the device.
• Incorrect mounting, commissioning, operation and maintenance of the device.
• Failure to observe the instructions in this operating manual regarding transport,
commissioning, operation and maintenance of the device.
• Unauthorised changes to the device made by parties other than the manufacturer.
• Non-observance of technical data.
• Repairs carried out incorrectly and the use of replacement parts or accessories not
approved by the manufacturer.
• Catastrophes caused by external influences and force majeure.
• Mounting and installation with device combinations not recommended by the
manufacturer.
This operating manual, especially the safety instructions, must be observed by all person-
nel working on the device. Furthermore, the rules and regulations that apply for accident
prevention at the place of use must be observed.
1.7 Disposal
Abide by the national regulations and laws governing the disposal of this device. Ask
your supplier if you are not sure how to dispose of the old equipment.
The directive on waste electrical and electronic equipment (WEEE directive) and the di-
rective on the restriction of certain hazardous substances in electrical and electronic
equipment (RoHS directive) apply in the European Community. In Germany, these poli-
cies are implemented through the "Electrical and Electronic Equipment Act" (ElektroG).
According to this, the following applies:
• Electrical and electronic equipment are not part of household waste.
• Batteries and accumulators are not part of household waste and must be disposed
of in accordance with the regulations.
• Old electrical and electronic equipment from users other than private households
which was introduced to the market after 13 August 2005 must be taken back by the
manufacturer and disposed of properly.
For more information on the disposal of Bender devices, refer to our homepage at
www.bender-de.com -> Service & Support.

isoMIL685D-D-P_D00263_04_M_XXEN/03.2021
9
Safety instructions
2. Safety instructions
2.1 General safety instructions
Part of the device documentation in addition to this manual is the enclosed "Safety in-
structions for Bender products".
2.2 Work activities on electrical installations.
If the device is used outside the Federal Republic of Germany, the applicable local stand-
ards and regulations must be complied with. The European standard EN 50110 can be
used as a guide.
Read the operating manual before starting to install, connect and com-
mission the device. After successful commissioning, keep the manual
within easy reach for future reference.
Only qualified personnel are permitted to carry out the work necessary
to install, commission and run a device or system.
DANGER
Risk of electrocution due to electric shock!
Touching live parts of the system carries the risk of:
• A fatal electric shock
• Damage to the electrical installation
• Destruction of the device
Before installing and connecting the device, make sure that the in-
stallation has been de-energised. Observe the rules for working on elec-
trical installations.
2.3 Device-specific safety information
2.4 Intended use
The ISOMETER® iso685… monitors the insulation resistance of unearthed AC/DC main
circuits (IT systems) with nominal system voltages of AC 0…690 V or DC 0…1000 V.
DC components existing in AC/DC systems do not influence the operating characteristics.
A separate supply voltage allows de-energised systems to be monitored too. The maxi-
mum permissible system leakage capacitance is 0…1000 µF, depending on the profile.
Intended use also implies:
• Reading and observing all information in the operating manual
• Compliance with test intervals
In order to meet the requirements of applicable standards, customised parameter set-
tings must be made on the equipment in order to adapt it to local equipment and oper-
ating conditions. Please heed the limits of the area of application indicated in the
technical specifications.
Any other use than that described in this manual is regarded as improper.
Installation inside a control cabinet
If the ISOMETER® is installed inside a control cabinet, the insulation fault
message must be audible and/or visible to attract attention.
IT systems with several ISOMETER®s
Make sure that only one active ISOMETER® is connected in each intercon-
nected system. If IT systems are interconnected via coupling switches,
make sure that ISOMETER®s not currently used are disconnected from the
IT system and deactivated. For IT systems coupled via diodes or capaci-
tances a central control of the different ISOMETER®s is required.
Prevent measurement errors!
When a monitored IT system contains galvanically coupled DC circuits, an
insulation fault can only be detected correctly if the rectifier valves (e.g.
rectifier diode, thyristors, IGBTs, frequency inverters, …) carry a minimum
current of > 10 mA.
Unspecified frequency range
When connecting to an IT system with frequency components below the
specified frequency range, the response times and response values may
differ from the indicated technical data. However, depending on the ap-
plication and the selected measurement method, continuous insulation
monitoring is also possible in this frequency range.

isoMIL685D-D-P_D00263_04_M_XXEN/03.2021
10
Function
3. Function
3.1 Features
• ISOMETER® for IT AC systems with galvanically connected rectifiers or inverters and
for IT DC systems (IT = unearthed systems)
• Automatic adaptation to the existing system leakage capacitance
• Combination of AMPPLUS and other profile-specific measurement methods
• Two separately adjustable response value ranges of 1 k…10 M
• High-resolution graphical LC display
• Connection monitoring (monitoring of the measuring lines)
• Automatic device self test
• Graphical representation of the insulation resistance over time (isoGraph)
• History memory with real-time clock (buffer for three days) for storing 1023 alarm
messages with date and time
• Current or voltage output 0(4)…20 mA, 0…400 A, 0…10 V, 2…10 V (galvanically
separated), which is analogous to the measured insulation value of the system
• Freely programmable digital inputs and outputs
• Remote setting via the Internet or Intranet
(Webserver/Option: COMTRAXX® gateway)
• Remote diagnosis via the Internet (made available by Bender Service only)
• RS-485/BS (Bender sensor bus) for data exchange with other Bender devices via
Modbus RTU protocol
• BCOM, Modbus TCP und web server
• ISOnet: Internal separation of the ISOMETER® from the IT system to be monitored
(e.g. if several IT systems are interconnected)
• ISOnet priority: Permanent priority of a device within the network
• ISOloop: Special function for ring systems (all systems are coupled)
• isoData: Continuous uninterrupted data transmissionLocating current injection for
selective insulation fault location
• Indication of the insulation faults selectively located by the EDS system
• Parameter setting of EDS systems
• EDSsync: Synchronous distribution of trigger information in coupled systems
• Customer-specific texts for each measuring channel
3.1.1 Features EDS44x
• Insulation fault location in AC, 3AC and DC IT systems
• Up to 12 measuring current transformers of the W…, WR…, WS… measuring cur-
rent transformer series can be connected
• Response sensitivity insulation fault location:
EDS440 2…10 mA
EDS441 0.2…1 mA
• Response sensitivity residual current measurement:
EDS440 100 mA…10 A
EDS441 100 mA…1 A
Communication of the components via BS bus (RS-485) or BB bus
3.2 Product description
The ISOMETER® isoMIL685W-D-P is an insulation monitoring device for IT systems in ac-
cordance with
IEC 61557-8 and IEC61557-9.
It is universally applicable in AC, 3(N)AC, AC/DC and DC systems. AC systems may include
extensive DC-supplied loads (such as rectifiers, inverters, variable-speed drives).
3.3 Function description
The insulation monitoring device continuously monitors the entire insulation resistance
of an IT system during operation and triggers an alarm when the value falls below a pre-
set response value. To obtain a measurement the device has to be connected between
the IT system (unearthed system) and the protective earth conductor (PE). A measuring
current in the ?A range is superimposed onto the system which is recorded and evaluated
by a microprocessor-controlled measuring circuit. The measuring time is dependent on
the selected measurement profiles, the system leakage capacitance, the insulation re-
sistance and possible system-related disturbances.
The response values and other parameters are set using a commissioning wizard as well
as via different setup menus using the device buttons and a high-resolution graphical LC
display. The selected settings are stored in a permanent fail-safe memory. Different
languages can be selected for the setup menus as well as the messages indicated on the
display. The device utilises a clock for storing fault messages and events in a history
memory with time and date stamp. The settings can be password protected to prevent
unauthorised changes.
To ensure proper functioning of connection monitoring, the device requires the setting
of the system type 3AC, AC or DC and the required use of the appropriate terminals L1/+,
L2, L3/-.

FunctionFunction
isoMIL685D-D-P_D00263_04_M_XXEN/03.2021
11
The insulation monitoring device iso685… is able to measure the insulation resistance
reliably and precisely in all common IT systems (unearthed systems). Due to various
applications, system types, operating conditions, application of variable-speed drives,
high system leakage capacitances etc., the measurement technique must be able to meet
varying requirements in order to ensure an optimised response time and relative
uncertainty. Therefore different measuring profiles can be selected with which the device
can optimally adjusted.
If the preset response value falls below the value of Alarm 1 and/or Alarm 2, the associa-
ted alarm relays switch, the LEDs ALARM 1 or ALARM 2 light and the measured value is
shown on the LC display (in case of insulation faults in DC systems, a trend graph for the
faulty conductor L+/L- is displayed). If the fault memory is activated, the fault message
will be stored. Pressing the RESET button resets the insulation fault message, provided
that the current insulation resistance displayed at the time of resetting is at least 25 %
above the actual response value.
As additional Information, the quality of the measuring signal and the time required to
update the measured value are shown on the display. A poor signal quality (1-2 bars) may
be an indication that the wrong measurement profile has been selected.
The ISOMETER® has an internal system isolating switch, which makes it possible to opera-
te several ISOMETER®s in coupled IT systems. For this purpose, the ISOMETER®s are con-
nected via an Ethernet bus. The integrated ISOnet function ensures that only one
ISOMETER® is actively measuring at a time, while the other devices are completely iso-
lated from the system and waiting in standby mode for measuring permission.
The ISOMETER® is able to synchronise itself with other ISOMETER®s. This makes it possible
to monitor capacitive coupled IT systems without interfering with each other.
3.4 Insulation fault location
An additional function of the ISOMETER® in combination with the EDS is the selective in-
sulation fault location. For this purpose, the ISOMETER® generates a periodic locating cur-
rent after the measured value has fallen below the set response value Ran2 ("ALARM 2"
LED). Thereby, the system conductors are alternately connected to earth via a defined re-
sistance. The resulting locating current depends on the size of the existing insulation fault
and the system voltage. It is limited by the ISOMETER® depending on the settings. The in-
sulation fault is selectively located by means of the EDS and the measuring current trans-
former connected to it. The locating current flows from the locating current injector via
the live lines to the insulation fault position taking the shortest way. From there, it flows
through the insulation fault and the conductor PE back to the ISOMETER®. This locating
current pulse is detected by the measuring current transformer on the insulation fault
path and signalled by the connected EDS.
For the duration of the insulation fault location, the function of the insulation monitoring
device is deactivated. If during the insulation fault location the locating current falls
below the value measurable by the EDS, the insulation fault location is ended by the
ISOMETER®.
Caution
Risk of malfunctions due to excessive locating current on sensitive
system parts!
The locating current flowing between the IT system and earth can cause
controller faults in sensitive parts of the system, such as the PLC or relay.
Ensure that the level of the locating current is compatible with the system
to be monitored.

FunctionFunction
isoMIL685D-D-P_D00263_04_M_XXEN/03.2021
12
3.4.1 Compatibility with EDS-devices
Full compatibility, communication with ISOMETER® via BS bus
Full compatibility, communication with ISOMETER® via BB bus
Full compatibility, no communication with ISOMETER®
3.5 Interfaces
• Communication protocol Modbus TCP
• Communication protocol Modbus RTU
• BCOM for communication of Bender devices via Ethernet
• BS bus for communication of Bender devices (RS-485)
• BB bus (Bender backbone bus)
• isoData for recording and managing measured values
• Integrated web server for reading out measured values and setting parameters
Device Notes Articleno.
EDS440-L EDS440-L
EDS440W-L
B91080202
B91080202W
EDS441-L EDS441-L
EDS441W-L
B91080205
B91080205W
EDS441-LAB EDS441-LAB
EDS441W-LAB
B91080207
B91080207W
EDS460/490L
Not recommended for new systems
EDS460/490D
EDS461/491L
EDS461/491D
Device Notes Articleno.
EDS440-S EDS440-S
EDS440W-S
B91080201
B91080201W
EDS441-S EDS441-S
EDS441W-S
B91080204
B91080204W
Device Notes Articleno.
EDS195P EDS195P B91082040
3.6 Self test
After switching on the supply voltage, the ISOMETER® automatically and continuously
checks all internal measuring functions, the components of the process control such as
the data and parameter memory, as well as the connections to the IT system and earth.
The self test can also be activated manually by means of the test button to check the func-
tions of the relays (depending on the configuration) or it can be selected via the "Control"
menu (refer to „Control“).
If the relays are checked during the self-test, they switch for 2 seconds.
The progress of the manual self test is shown on the LC display by a bar graph. Depending
on the conditions in the IT system being monitored, the self test is completed after 15...20
seconds. The device then returns to the standard mode (measurement mode) and the ac-
tual measured value will be displayed after the measuring time has expired. The display
shows the message
Initial measurement until the first valid value is measured (refer to
„Initial measurement“).
If a fault is detected during the self test, the respective LEDs of the device light (refer to
„Alarm messages“). In addition, the respective message will be indicated on the display
and a previously programmed output will provide the respective signal.
√
33 %
Test successful
Test unsuccessful
Test not available
(e.g. incorrect device settings).
Test is being carried out.
Measurement
technique
Coupling
Connection
TEST

isoMIL685D-D-P_D00263_04_M_XXEN/03.2021
13
Device overview
4. Device overview
4.1 Dimensions
Enclosure iso685…-device familiy – dimensions in mm
93
108
110
4.2 Device variants
iso685(W)-D…
isoxx685(W)-D…
The iso685 variant features a high-resolution graphic LC display and
operating controls for direct operation of the device functions.
It cannot be combined with an FP200.

Device overview
isoMIL685D-D-P_D00263_04_M_XXEN/03.2021
14
4.3 Connection and panel
11 12 13 14
10
Top 10 A1/+, A2/- Connection to the power supply voltage Us
11 L1/+ Connector for the IT system to be monitored
12 L2 Connector for the IT system to be monitored
13 L3/- Connector for the IT system to be monitored
14 KE, E Connection to PE
5050505050505050505050
20 X4 REMOTE interface to connect the FP200(W) *
50 X3 Optional expansion interface for Bender products
Rear
Front
Connction bottom
Control panel
Connection top
iso685(W)-D… and isoxx685(W)-D…
242221141211RETHX1
1918
1716
15
15 X1 Multifunctional I/O interface (see „Connection of the X1 interface“)
16 ETH (X2) Ethernet interface
17 R Switchable terminating resistor for termination of the RS-485 interface
18 11 12 14 Connector for alarm relay 1
19 21 22 24 Connector for alarm relay 2
Bottom

Device overviewDevice overview
isoMIL685D-D-P_D00263_04_M_XXEN/03.2021
15
4.4 Display elements and device buttons
4.4.1 Display elements
1 ON The "ON" LED lights when the device is turned on.
2PGHON
The "PGH ON" LED flashes during insulation fault location. It indicates that
the locating current for the insulation fault location is generated.
3 SERVICE The "SERVICE" LED lights when there is either a device fault or a connection
fault, or when the device is in maintenance mode.
4 ALARM 1 The "ALARM 1" LED lights when the insulation resistance of the IT system
falls below the set response value Ran1.
5 ALARM 2 The "ALARM 2" LED lights when the insulation resistance of the IT system
falls below the set response value Ran2.
6Display
The device display shows information regarding the device and the meas-
urements. Other information is available in chapter „Display“.
1
3
4
5
6
78
910
11 12
PGH ON
2
4.4.2 device buttons
You can adjust the device settings in the respective menu using the menu buttons. De-
pending on the menu entry, one of the options displayed below is assigned to the but-
tons.
7EDS Manually starts the insulation fault location, which runs continuously.
Stops the insulation fault location immediately when it is pressed again.
Navigates up in a list or increases a value.
8
MENU Opens the device menu.
ESC Cancels the current process or
navigates one step back in the device menu.
9
RESET Resets alarms.
Navigates backwards (e.g. to the previous setting step) or
selects a parameter.
10
TEST Starts the device self test.
Navigates forwards (e.g. to the next setting step) or
selects a parameter.
11 DATA Indicates data and values.
Navigates down in a list or reduces a value.
12 INFO Shows information.
OK Confirms an action or a selection.

Device overviewDevice overview
isoMIL685D-D-P_D00263_04_M_XXEN/03.2021
16
4.5 Operating and navigating
4.5.1 Menu selection
4.5.2 List selection
4.5.3 Parameter selection and value adjustment
Activate the menu by pressing the
"MENU" button
IT system
230 k Ω
OK
R(an) 100k Ω /20k Ω
Commissioning
x.6
2/1x
date and time
Please set thr current
Use the button to select menu items.
Press "ESC" to return form the respective
menu level.
An overview of the device menu can be
found in chapter .
Use the buttons and to select values
from a predefined list (menu). The present
value is indicated by a black menu item.
Confirm the value with the "OK" button.
Exit the list selection by pressing "ESC".
System type
x.6.6
• DC
o AC
o 3AC
Date
x.6.4
28.07.2016
Min.
Max.
1
12
Use the and buttons to select a pa-
rameter. The present parameter is indicat-
ed by the symbols. Values can be
changed using the and buttons. Con-
firm input text by pressing "OK". Exit text
input by pressing "ESC".
4.5.4 Character input
4.5.5 Multiple selection in the device menu
Use the (forward) and (backward)
buttons to select a character from the dis-
play. To enter the next character, use the
button to select the next position.
To delete a character that has been en-
tered, use the and buttons to select
the position of the character to be deleted
and then select "del" using the and
buttons.
Confirm the entered text with "OK". Exit
the character input by pressing "ESC".
Ethernet
x.3.2
192.
ghijklmnopqrstuvwxyz
-.0123456789abcdef
Activate channel
2.3
Select all
Channel 1 (BS 2/1)
Channel 2 (BS 2/2)
No selection
Invert selection
Use the and buttons to select options
(Select all, No selection, Invert selection) and
channels. Every selection has to be con-
firmed by pressing "OK".
For the selected channels, press the but-
ton to activate OR to jump to the next sub-
menu.
Exit the menu by pressing "ESC".

isoMIL685D-D-P_D00263_04_M_XXEN/03.2021
17
Mounting
5. Mounting
5.1 Common information
Only qualified personnel are permitted to carry out the work necessary
to install, commission and run a device or system.
Read the manual before you begin to mount, connect, and commission
the unit. Always keep the manual within easy reach for future reference
following commissioning.
DANGER
Danger of electrocution due to electric shock!
Touching live parts of the system carries the risk of:
• A life threatening electric shock
• Damage to the electrical installation
• Destruction of the device
Before installing and connecting the device, make sure that the
installation has been de-energised. Observe the rules for working on
electrical installations.
5.2 Mounting spaces
0 mm0 mm
20 mm
20 mm

MountingMounting
isoMIL685D-D-P_D00263_04_M_XXEN/03.2021
18
5.3 Screw mounting
1. Fix the three mounting clips delivered with the device (two of them packed
separately) manually or using a tool, as illustrated below.
2. Drill the mounting holes for the M4 thread according to the drilling template.
3. Fix the ISOMETER® using three M4 screws..
Dimensions in mm
108
107,3
100
72
54
Ø M4
5.4 DIN rail mounting
1. Fix the three mounting clips delivered with the device (two of them packed
separately) manually or using a tool, as illustrated below.
2. Mount the ISOMETER® onto the DIN rail.
3. Fix the ISOMETER® onto the DIN rail by pressing the mounting clips until they snap
into place
Dimensions in mm
Mounting clips
The installation of a third mounting clip is only required for "W variants".
108
54
18
click!
click!
click!

isoMIL685D-D-P_D00263_04_M_XXEN/03.2021
19
Connection
6. Connection
6.1 Connection conditions
In accordance with VDE 0100, only qualified personnel are permitted to
carry out the work necessary to install, commission and run a device or
system.
DANGER
Risk of electrocution due to electric shock!
Touching live parts of the system carries the risk of:
• A fatal electric shock
• Damage to the electrical installation
• Destruction of the device
Before installing and connecting the device, make sure that the ins-
tallation has been de-energised. Observe the rules for working on elec-
trical installations.
DANGER
Risk of electric shock!
High voltages may be present at terminals "L1/+" to "L3/-". Direct contact
with these will likely result in electrocution.
• Therefore, the device is only to be operated with mounted and locked
terminal covers.
• If the device is connected to a live IT system via terminals "L1/+", "L2",
"L3/-", do not disconnect terminals "KE" and "E" from the protective
conductor ("PE").
• Connect terminals "KE" and "E" individually to the protective earth con-
ductor "PE".
CAUTION
Provide line protection!
According to DIN VDE 0100-430, line protection shall be provided for the
supply voltage.
Risk of injury from sharp-edged terminals!
Risk of lacerations.
Touch the enclosure and the terminals with due care.
Ensure disconnection from the IT system!
When insulation or voltage tests are to be carried out, the device must be
isolated from the system for the test period. Otherwise the device may be
damaged.
Property damage due to improper installation!
Make sure that only one insulation monitoring device is connected in
each conductively connected system. If several devices are connected, the
device does not work and does not signal insulation faults. This can da-
mage the installation.
High load currents can result in property damage and injury. Therefore,
do not apply any load current to the terminals. The connecting lines "L1/
+", "L2", "L3/-" to the system to be monitored must be designed as spur li-
nes.
Failure to connect the device as illustrated in the manual leads to deviating
technical data and function restrictions.
Check proper connection!
Prior to commissioning the installation, check that the device has been
properly connected and check the device functions. Perform a functional
test using an earth fault via a suitable resistance.
Prevent measurement errors!
When a monitored AC system contains galvanically coupled DC circuits,
the following applies: An insulation fault can only be detected correctly
when the rectifier valves carry a minimum current of > 10 mA.
For UL applications:
Use 60/75 °C copper lines only!
For UL and CSA applications, the supply voltage must be protected via 5 A
fuses.

ConnectionConnection
isoMIL685D-D-P_D00263_04_M_XXEN/03.2021
20
6.2 Connection to a 3(N)AC system
WARNING
Injury, fire and damage to property due to a short circuit!
According to DIN VDE 0100-430, devices used to protect against short cir-
cuits when terminals "L1/+", "L2" und "L3/-" are coupled to the IT system to
be monitored can be omitted if the wiring is designed in such a manner
that the risk of a short circuit is reduced to a minimum. Ensure short-cir-
cuit-proof and earth-fault-proof wiring.
A1/+ A2/- L1/+ L2 L3/- KE E
US
Un
L3
N
L2
L1
E
KE
L3/-
L2
L1/+A2/–A1/+
Fback-up Fback-up
6.3 Connection to an AC system
WARNING
Injury, fire and damage to property due to a short circuit!
According to DIN VDE 0100-430, devices used to protect against short cir-
cuits when terminals "L1/+", "L2" und "L3/-" are coupled to the IT system to
be monitored can be omitted if the wiring is designed in such a manner
that the risk of a short circuit is reduced to a minimum. Ensure short-cir-
cuit-proof and earth-fault-proof wiring.
A1/+ A2/- L1/+ L2 L3/- KE E
US
UnL2
L1
L2
L1
E
KE
L3/-
L1/+A2/–A1/+
Fback-up Fback-up