Connecting Logo!'S Inputs - Siemens LOGO! Series Manual

Installing and wiring LOGO!

2.2.2 Connecting LOGO!'s inputs

Requirements
You connect sensors to the inputs. The sensors may be switches, photo-
electric barriers or daylight control switches, for example.
Sensor attributes for LOGO! 230R and LOGO! 230RC
S
LOGO! recognizes the switch state 0 (switch open) at  40 V AC. The
maximum input current is 0.24 mA (switches with glow lamps can
cause problems if the closed-circuit current of the glow lamps is
greater than 0.2 mA. Connect these switches to LOGO! via a relay, or
use switches where the glow lamp is connected via an additional n-type
conductor).
S
LOGO! recognizes the switch state 1 (switch open) at  79 V AC
(switch closed).
S
You cannot connect 2-wire proximity switches to LOGO! directly be-
cause of their high closed-circuit current.
S
When the switch state changes from 0 to 1, switch state 1 must exist
for at least 50 ms for LOGO! to recognize it. The same applies to state
0 when the change is in the opposite direction.
Sensor attributes for LOGO! 24 and LOGO! 24 R
S
LOGO! recognizes the switch state 0 (switch open) at  5 V DC. The
input current is typically 3 mA.
S
LOGO! recognizes the switch state 1 (switch closed) at  15 V DC.
S
You can connect 3- and 4-wire proximity switches with a separate volt-
age supply to LOGO!. You cannot connect 2-wire proximity switches
to LOGO! directly because of their high closed-circuit current.
S
When the switch state changes from 0 to 1, switch state 1 must exist
for at least 50 ms for LOGO! to recognize it. The same applies to state
0 when the change is in the opposite direction.
6 LOGO! manual
EWA 4NEB 712 6006-02