Siemens SIMATIC User Manual

Analog modules
6.10 Analog input module SM 331; AI 8 x TC; (6ES7331-7PF11-0AB0)
S7-300 Module data
Manual, 06/2017, A5E00105505-AJ
403
Technical specifications
Encoder selection data
Input ranges (rated values) / input impedance
• Thermocouples
Types B, C, N, E, R, S, J, L, T, K, U, TxK/xK (L)/ > 10
megaohms
Maximum voltage at voltage input (destruction limit) 20 V DC continuous; 75 V DC for the duration of max. 1 s
(duty factor 1:20)
Characteristics linearization programmable
Temperature compensation
• Internal temperature compensation
• External temperature compensation with Pt 100 (0.003850)
• Compensation for 0 °C reference junction temperature
• Compensation for 50 °C reference junction temperature
• Technical unit of temperature measurement
programmable
supported
supported
supported
supported
Degrees Centigrade / degrees Fahrenheit
Wiring of the signal transmitters
using a 40-pin front connector
** Wire-break monitoring in 4-channel mode (hardware filter) at intervals of three seconds.
** In 8-channel software mode (software filter), series-mode rejection is reduced as follows:
• 50 Hz > 70 dB
• 60 Hz > 70 dB
• 400 Hz > 80 dB
*** The operational limit comprises only the basic error of the analog input at Ta = 25 °C and the total temperature error.
The total error must include the compensation error of the cold reference junction. Internal compensation of the reference
junction = max. 1.5 °C
External compensation of the reference junction = accuracy of the used external RTD ± 0.1 °C.
External compensation of the reference junction at which the reference junction is maintained at 0 °C or 50 °C = accuracy
of the temperature control of the reference junction.
**** Du
e to its small slope of approx. 0 °C to 40 °C, a lack of compensation for the reference junction temperature only has
a slight effect with thermocouple type B. With missing compensation and set measuring type "Compensation to 0 °C", the
deviation with thermocouple type B at measuring temperatures between:
• 700 °C and 1820 °C is < 0.5 °C
• 500 °C and 700 °C is < 0.7 °C.
If the reference junction temperature is approximately that of the module temperature, "internal compensation" should be
set. As a result, the error for the temperature range from 500 °C to 1820 °C is reduced to < 0.5 °C.
***** In 4-channel mode, the converted value settles to 100 % within 80 ms. The value determined in this process is set at
intervals of 3.3 ms (max. 10 ms).
****** If internal or external reference junction compensation is configured, the measured values of all channels are not
updated for about 1 s in each minute. ###

Siemens SIMATIC Specifications

General

Product type designation	SIMATIC
CPU	Varies by model
Memory	Varies by model
Input/Output	Varies by model
Communication	Varies by model
Programming Language	STEP 7
Operating Temperature	0°C to 60°C (varies by model)
Protection Class	IP20
Category	Programmable Logic Controller (PLC)