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  • 300S+

321-1BH70 - Signal modules digital | Digital input modules

Order no.


TypeSM 321S - SPEED-Bus

General information

Features16x fast DI
Parameterizable as Alarm/ETS
For 20 pole front connector

Current consumption/power loss

Current consumption from backplane bus390 mA
Power loss5 W

Technical data digital inputs

Number of inputs16
Cable length, shielded1000 m
Cable length, unshielded600 m
Rated load voltageDC 20.4...28.8 V
Current consumption from load voltage L+ (without load)15 mA
Rated valueDC 24 V
Input voltage for signal "0"DC 0...5 V
Input voltage for signal "1"DC 15...28.8 V
Input voltage hysteresis-
Signal logic inputSinking input
Frequency range-
Input resistance-
Input current for signal "1"7 mA
Connection of Two-Wire-BEROs possible
Max. permissible BERO quiescent current1.5 mA
Input delay of "0" to "1"parameterizable 2.56µs - 40ms
Input delay of "1" to "0"parameterizable 2.56µs - 40ms
Number of simultaneously utilizable inputs horizontal configuration16
Number of simultaneously utilizable inputs vertical configuration16
Input characteristic curveIEC 61131-2, type 1
Initial data size2 Byte

Status information, alarms, diagnostics

Status displaygreen LED per channel
Process alarmyes, parameterizable
Diagnostic interruptyes, parameterizable
Diagnostic functionsyes
Diagnostics information read-outpossible
Supply voltage displaygreen LED
Group error displaynone
Channel error displaynone


Between channels-
Between channels of groups to16
Between channels and backplane bus
Insulation tested withDC 500 V


Input bytes2 / 48
Output bytes0
Parameter bytes0 / 66
Diagnostic bytes16


MountingDIN rail SPEED-Bus

Mechanical data

Dimensions (WxHxD)40 mm x 125 mm x 120 mm
Net weight190 g
Weight including accessories-
Gross weight-

Environmental conditions

Operating temperature0 °C to 60 °C
Storage temperature-25 °C to 70 °C


UL certificationyes
KC certification-