SIEMENS Digital modules SM 1221 digital input modules

Overview

  • Digital inputs as supplement to the integral I/O of the CPUs
  • For flexible adaptation of the controller to the relevant task
  • For subsequent expansion of the system with additional inputs
 SM 1221 digital input modules

Application

Digital input modules allow the connection of the controller to digital signals of the process.

This provides users with the following advantages:

  • Optimum adaptation:
    With signal modules which can be mixed as desired, users can adapt their controllers exactly to the relevant task. This avoids superfluous investments. Modules with 8, 16, and 32 input/output channels are available.
  • Flexibility:
    If the task is expanded subsequently, the controller can be upgraded. Updating of the user program is extremely simple.

Function

The SM 1221 digital input signal modules convert the level of the external digital signals from the process into the internal signal level of the S7-1200.

SIEMENS I/O modules SM 1221 digital input modules Ordering data

Product No. / Product Description Listprice / Your price
6ES7221-1BF32-0XB0
SIMATIC S7-1200, DIGITAL INPUT SM 1221, 8DI, 24V DC, SINK/SOURCE INPUT
6ES7221-1BH32-0XB0
SIMATIC S7-1200, DIGITAL INPUT SM 1221, 16 DI, 24VDC, SINK/SOURCE INPUT

Technical specifications

Article number

6ES7221-1BF32-0XB0

6ES7221-1BH32-0XB0

DIGITAL INPUT SM 1221, 8DI, 24V DC

DIGITAL INPUT SM 1221, 16DI, 24V DC

Supply voltage

Rated value (DC)

  • ● 24 V DC

Yes

Yes

permissible range, lower limit (DC)

20.4 V

20.4 V

permissible range, upper limit (DC)

28.8 V

28.8 V

Input current

from backplane bus 5 V DC, max.

105 mA

130 mA

Digital inputs

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

4 mA; per channel

4 mA; per channel

Output voltage

Power supply to the transmitters

  • ● present

Yes

Yes

Power loss

Power loss, typ.

1.5 W

2.5 W

Digital inputs

Number of digital inputs

8

16

  • ● in groups of

2

4

Input characteristic curve in accordance with IEC 61131, type 1

Yes

Yes

Number of simultaneously controllable inputs

all mounting positions

  • — up to 40 °C, max.

8

16

horizontal installation

  • — up to 40 °C, max.

8

16

  • — up to 50 °C, max.

8

16

vertical installation

  • — up to 40 °C, max.

8

16

Input voltage

  • ● Type of input voltage

DC

DC

  • ● Rated value (DC)

24 V

24 V

  • ● for signal “0”

5 V DC at 1 mA

5 V DC at 1 mA

  • ● for signal “1”

15 V DC at 2.5 mA

15 V DC at 2.5 mA

Input current

  • ● for signal “0”, max. (permissible quiescent current)

1 mA

1 mA

  • ● for signal “1”, min.

2.5 mA

2.5 mA

  • ● for signal “1”, typ.

4 mA

4 mA

Input delay (for rated value of input voltage)

for standard inputs

  • — parameterizable

Yes; 0.2 ms, 0.4 ms, 0.8 ms, 1.6 ms, 3.2 ms, 6.4 ms and 12.8 ms, selectable in groups of four

Yes; 0.2 ms, 0.4 ms, 0.8 ms, 1.6 ms, 3.2 ms, 6.4 ms and 12.8 ms, selectable in groups of four

for interrupt inputs

  • — parameterizable

Yes

Yes

Cable length

  • ● shielded, max.

500 m

500 m

  • ● unshielded, max.

300 m

300 m

Interrupts/diagnostics/status information

Alarms

  • ● Diagnostic alarm

Yes

Yes

Diagnostics indication LED

  • ● for status of the inputs

Yes

Yes

Potential separation

Potential separation digital inputs

  • ● between the channels, in groups of

2

4

Degree and class of protection

Degree of protection acc. to EN 60529

  • ● IP20

Yes

Yes

Standards, approvals, certificates

CE mark

Yes

Yes

CSA approval

Yes

Yes

UL approval

Yes

Yes

cULus

Yes

Yes

FM approval

Yes

Yes

RCM (formerly C-TICK)

Yes

Yes

Marine approval

Yes

Ambient conditions

Free fall

  • ● Fall height, max.

0.3 m; five times, in product package

0.3 m; five times, in product package

Ambient temperature during operation

  • ● min.

-20 °C

-20 °C

  • ● max.

60 °C

60 °C

  • ● horizontal installation, min.

-20 °C

  • ● horizontal installation, max.

60 °C

  • ● vertical installation, min.

-20 °C

  • ● vertical installation, max.

50 °C

  • ● permissible temperature change

5°C to 55°C, 3°C / minute

5°C to 55°C, 3°C / minute

Ambient temperature during storage/transportation

  • ● min.

-40 °C

-40 °C

  • ● max.

70 °C

70 °C

Air pressure acc. to IEC 60068-2-13

  • ● Storage/transport, min.

660 hPa

660 hPa

  • ● Storage/transport, max.

1 080 hPa

1 080 hPa

Relative humidity

  • ● Operation at 25 ℃ without condensation, max.

95 %

95 %

Connection method

required front connector

Yes

Yes

Mechanics/material

Enclosure material (front)

  • ● Plastic

Yes

Yes

Dimensions

Width

45 mm

45 mm

Height

100 mm

100 mm

Depth

75 mm

75 mm

Weights

Weight, approx.

170 g

210 g