Parameters/address space
4.1 Measurement types and measuring ranges
Analog input module AI 4xRTD/TC 2-/3-/4-wire HF (6ES7134-6JD00-0CA1)
Manual, 02/2014, A5E03573289-AD
15
Special features when using PTC resistors
PTCs are suitable for monitoring temperature and/or as thermal protection devices of
complex drives or transformer windings.
● Choose "Thermal resistor (2-wire)" and "PTC" in the parameter assignment.
● Connect the PTC to the 2-wire connection technology.
● Use the PTC resistors, type A (PTC thermistor) in accordance with DIN/VDE 0660,
part 302.
● If "Underflow" diagnostic is enabled, a "Low limit violated" diagnostic is generated for
resistance values < 18 Ω, indicating a short-circuit.
● Sensor data for the PTC resistor:
Table 4- 2 Using PTC resistors
Property Technical
specifications
Comment
Switching points Behavior with rising temperature
< 550 Ω Normal range:
• SIMATIC S7: Bit 0 = "0", Bit 2 = "0" (in the PII)
550 Ω to 1650 Ω Prewarning range:
• SIMATIC S7: Bit 0 = "0", Bit 2 = "1" (in the PII)
> 1650 Ω Response range:
• SIMATIC S7: Bit 0 = "1", Bit 2 = "0" (in the PII)
Behavior with falling temperature
> 750 Ω Response range:
• SIMATIC S7: Bit 0 = "1", Bit 2 = "0" (in the PII)
750 Ω to 540 Ω Prewarning range:
• SIMATIC S7: Bit 0 = "0", Bit 2 = "1" (in the PII)
< 540 Ω Normal range:
• SIMATIC S7: Bit 0 = "0", Bit 2 = "0" (in the PII)
Reaction to short-circuit
< 18 Ω
• SIMATIC S7: Bit 7 (IB x+1) = "1", Bit 0 = "0" and
Bit 2 = "0"
(RRT-5) °C
(RRT+5) °C
(RRT+15) °C
Measuring voltage/
voltage at the PTC
Max. 550 Ω
min. 1330 Ω
min. 4000 Ω
Max. 7.5 V
1
TNF = Rated response temperature of the sensor
(according to DIN/VDE 0660)
1
Below 23 kΩ