G

G-66

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CM Series Safety Interlock Switches

2-Wire Single Channel Controllers

CM-S41 Control Unit

The CM-S41 is a combined Safety Switch and E-Stop control

unit. Along with the ability to monitor up to four, 2-wire CM Series

safety switches, it can also monitor the normally closed contacts

of emergency stop buttons or mechanical safety switches in dual

channel control circuits.

The CM-S41 has 2 normally open safety contact outputs and 1

normally closed auxiliary output, an external reset/proving circuit

and LED indication for “Power”, “Run” and the status of each

activated gate switch.

CM-S21 Control Unit

The CM-S21 control unit is a 24 VAC/DC system that can moni-

tor up to 2 CM Series safety switches.

The CM-S21 has 2 normally open safety contact outputs and 1

normally closed auxiliary output, an external reset/proving circuit

and LED indication for “Power”, “Run” and the status of each

activated gate switch.

CM-SE Extender Module

The CM-SE expansion module is a 24 VAC/DC unit that can be

added to either the CM-S41 or CM-S21 to monitor an additional

5 CM Series safety switches. Connection to the main control

unit is by a simple 2-wire bus connection. The status of each

guard switch is shown by the YELLOW LED’s. Additional CMS-E

modules can be added to monitor larger systems.

Applications

CM-S21 Application Diagram

CM-S41 Application Diagram

CM-SE Application Diagram

RUN

POWER

GATE 4

GATE 3

4

3

2

1

GATE 4

GATE 3

GATE 2

DE-SELECT

A1 S13 S23 X1 BL DR BL DR 31 13 23

A2 S14 S24 X2 BL DR BL DR 32 14 24

GATE 2

GATE 1

GS3GS4

GS1GS2

K1

K2

MECHANICAL

SAFETY

SWITCHES

or

EMERGENCY

STOP

K1

K2

MANUAL

RE-SET

L (+ve)

N (-ve)

K1

K2

A1

BL

DR

GATE 1

GS1

24 V

+ve

0 V

-ve

BL

DR

BL

DR

GATE 2GATE 3

GS2 GS3

A2

BL

DR

GATE 4

GS4

BL

DR

BL

DR

GATE 5BUS

GS5

IND 1

IND 2

IND 3

IND 4

IND 5

2-WIRE BUS CONNECTION

POWER

BL DR

A2

A1

ISIS-4 or ISIS-2

CONTROL UNIT

Connect the ISIS-E

Bus connection to

Extender Module

Control Unit

CM-S41 / CM-S21 Control

Units:

Connect the CM-SE Bus

connection to an active

gate input.

GATE 2

A1 X1 BL DR 31 13 23

A2 X2 BL DR 32 14 24

GATE 1

GS2

GS1

K1

K2

K1

K2

24V

(+ve)

0V

(-ve)

K1

K2

POWER

IND 1

IND 2

RUN

MANUAL

RE-SET