SIEMENS S7-300 Ex analog input modules Product Information

OverviewEx analog input modules

  • Analog inputs for signals from the Ex field
  • For the connection of intrinsically safe analog equipment from the Ex field
  • 8 or 4 analog inputs in 4 channel groups (single-channel isolation)
  • Measurement type and range can be selected for each channel
  • Diagnostics and diagnostics alarm programmable
  • Programmable threshold alarm
  • HART-compatible inputs (only 6ES7331-7RD00-0AB0)

Application

Ex analog input modules are used for the connection of intrinsically-safe analog equipment from the Ex field.


Design

The Ex analog input modules have the following mechanical features:

  • Compact configuration;
    The rugged plastic housing contains:

    • A single red group fault LED for all circuits
    • One red LED each per channel for displaying channel-specific faults/errors, e.g., wire break or load break
    • Slot for front connector or cable guide, protected by the front cover
    • Labeling area on the front cover.
  • Easy installation:
    The module is mounted on the DIN rail and connected to the adjacent modules via bus connectors. There are no slot rules; the addresses of the inputs are predetermined by the slot.
  • User-friendly wiring:
    The modules are wired by means of a plug-in front connector. When they are first plugged in, a coding element clicks into place so that the connector will only fit into modules of the same type. The front connector contains a special barrier for covering the module’s 24 V load current supply. When the module is replaced, the front connector can be used in its fully wired state for the new module of the same type.

Function

The Ex analog input modules convert the analog signals of the intrinsically-safe equipment of the Ex field into digital values for further processing.


Technical specifications

Article number

6ES7331-7RD00-0AB0

6ES7331-7SF00-0AB0

SIMATIC S7, SM 331 ANALOG INPUT

SIMATIC S7, SM 331 ANALOG INPUT

Supply voltage

Load voltage L+

  • ● Rated value (DC)

24 V

24 V

  • ● Reverse polarity protection

Yes

Input current

from load voltage L+ (without load), max.

250 mA

from backplane bus 5 V DC, max.

60 mA

120 mA

Output voltage

Power supply to the transmitters

  • ● Rated value (DC)

13 V; at 22 mA

  • ● No-load voltage (DC)

25.2 V

Power loss

Power loss, typ.

3 W

0.6 W

Analog inputs

Number of analog inputs

4

8; 8x thermocouples; 4x RTD thermoresistors

permissible input current for current input (destruction limit), max.

40 mA

Input ranges

  • ● Voltage

No

Yes

  • ● Current

Yes

No

  • ● Thermocouple

No

Yes

  • ● Resistance thermometer

No

Yes

  • ● Resistance

No

Yes

Input ranges (rated values), currents

  • ● 0 to 20 mA

Yes

  • ● Input resistance (0 to 20 mA)

50 Ω

  • ● 4 mA to 20 mA

Yes

  • ● Input resistance (4 mA to 20 mA)

50 Ω

Input ranges (rated values), thermocouples

  • ● Type B

Yes

  • ● Input resistance (Type B)

10 MΩ

  • ● Type E

Yes

  • ● Input resistance (Type E)

10 MΩ

  • ● Type J

Yes

  • ● Input resistance (type J)

10 MΩ

  • ● Type K

Yes

  • ● Input resistance (Type K)

10 MΩ

  • ● Type L

Yes

  • ● Input resistance (Type L)

10 MΩ

  • ● Type N

Yes

  • ● Input resistance (Type N)

10 MΩ

  • ● Type R

Yes

  • ● Input resistance (Type R)

10 MΩ

  • ● Type S

Yes

  • ● Input resistance (Type S)

10 MΩ

  • ● Type T

Yes

  • ● Input resistance (Type T)

10 MΩ

  • ● Type U

Yes

  • ● Input resistance (Type U)

10 MΩ

Input ranges (rated values), resistance thermometer

  • ● Ni 100

Yes

  • ● Input resistance (Ni 100)

10 MΩ

  • ● Pt 100

Yes

  • ● Input resistance (Pt 100)

10 MΩ

  • ● Pt 200

Yes

  • ● Input resistance (Pt 200)

10 MΩ

Cable length

  • ● shielded, max.

200 m

200 m; TC: 50 m

Analog value generation for the inputs

Measurement principle

Sigma Delta

Sigma Delta

Integration and conversion time/resolution per channel

  • ● Resolution with overrange (bit including sign), max.

16 bit; 10 bit to 15 bit + sign

16 bit; 10 bit to 15 bit + sign

  • ● Integration time, parameterizable

Yes; 2.5 to 100 ms

Yes; 2.5 to 100 ms

  • ● Interference voltage suppression for interference frequency f1 in Hz

10 to 400 Hz

10 to 400 Hz

Encoder

Connection of signal encoders

  • ● for current measurement as 2-wire transducer

Yes

Yes

  • ● for current measurement as 4-wire transducer

Yes

Yes

Errors/accuracies

Temperature error (relative to input range), (+/-)

0.001 %/K; Temperature error: 0.001 to 0.002 %/K

Operational error limit in overall temperature range

  • ● Current, relative to input range, (+/-)

0.45 %

  • ● Resistance thermometer, relative to input range, (+/-)

0.04 %; 0.09 to 0.04%

Basic error limit (operational limit at 25 °C)

  • ● Current, relative to input range, (+/-)

0.1 %

  • ● Resistance thermometer, relative to input range, (+/-)

0.008 %; 0.018 … 0.008%

Interference voltage suppression for f = n x (f1 +/- 1 %), f1 = interference frequency

  • ● Series mode interference (peak value of interference < rated value of input range), min.

60 dB

60 dB

  • ● Common mode interference, min.

130 dB

130 dB

Interrupts/diagnostics/status information

Diagnostic functions

Yes

Yes

Diagnostic messages

  • ● Diagnostic information readable

Yes

Yes

  • ● Overrange

Yes

Yes

  • ● Wire-break in signal transmitter cable

Yes

Yes

  • ● Short-circuit of the signal encoder cable

Yes

Yes

Diagnostics indication LED

  • ● Group error SF (red)

Yes

Yes

  • ● Channel fault indicator F (red)

Yes

Yes

Ex(i) characteristics

Module for Ex(i) protection

Yes

Yes

Maximum values of input circuits (per channel)

  • ● Co (permissible external capacity), max.

90 nF

43 µF

  • ● Io (short-circuit current), max.

68.5 mA

28.8 mA

  • ● Lo (permissible external inductivity), max.

7.5 mH

40 mH

  • ● Po (power of load), max.

431 mW

41.4 mW

  • ● Ri, max.

50 Ω

  • ● Uo (output no-load voltage), max.

25.2 V

5.9 V

Potential separation

Potential separation analog inputs

  • ● Potential separation analog inputs

Yes

Yes

Permissible potential difference

between the inputs (UCM)

60 V DC/30 V AC when used in the hazardous area; 400 V DC/250 V AC when used in NON-hazardous area

60 V DC/30 V AC when used in the hazardous area; 400 V DC/250 V AC when used in NON-hazardous area

Between the inputs and MANA (UCM)

60 V DC/30 V AC when used in the hazardous area; 400 V DC/250 V AC when used in NON-hazardous area

60 V DC/30 V AC when used in the hazardous area; 400 V DC/250 V AC when used in NON-hazardous area

Use in hazardous areas

  • ● Type of protection acc. to EN 50020 (CENELEC)

[EEx ib] IIC

[EEx ib] IIC

  • ● Type of protection acc. to FM

Class I, Division 2, Group A, B, C, D T4

Class I, Division 2, Group A, B, C, D T4

  • ● Test number PTB

Ex-96.D.2092X

Ex-96.D.2108X

Ambient conditions

Ambient temperature during operation

  • ● max.

60 °C

60 °C

Connection method

required front connector

20-pin

20-pin

Weights

Weight, approx.

290 g

210 g