Siemens ET 200S Manual page 468

Analog Electronic Modules
Use of PTC Resistors
PTCs are suitable for temperature monitoring and as thermal protective devices for
complex drives and transformer windings.
S Select "Two-conductor resistor" and "PTC" at parameter assignment:
S Connect the PTC in accordance with the two-conductor connection method.
S Apply PTC resistors of type A (PTC thermistors) in accordance with DIN /
VDE 0660, Part 302.
S Sensor data for the PTC resistor:
Feature
Switching points
(TNF–5) _C
(TNF+5) _C
(TNF+15) _C
Measuring voltage
Voltage on the
PTC
12-112
Technical
specifications
On/reset Measured resistance < response
threshold
Max. 750 Ω
S
S
Off Temperature increase
From 1650Ω to 4000Ω Measured resistance > response
threshold
S
S
On/reset Temperature decrease
From 1650Ω to 750Ω Measured resistance < response
threshold
S
S
Max. 550Ω TNF= rated operating temperature
Min. 1330Ω
Min. 4000Ω
Max. 7.5 V
Remarks
SIMATIC S7: bit 0 = "0" (in the PII)
SIMATIC S5: bit 3 = "0" (in the PII)
SIMATIC S7: bit 0 = "1" (in the PII)
SIMATIC S5: bit 3 = "1" (in the PII)
SIMATIC S7: bit 0 = "0" (in the PII)
SIMATIC S5: bit 3 = "0" (in the PII)
Distributed I/O System ET 200S
EWA 4NEB 780 6024-02 07