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  • 300S+

321-1FH00 - Signal modules digital | Digital input modules

Order no.


TypeSM 321

General information

Features16x DI, in groups of 4
AC 120/230 V
For 20 pole front connector

Current consumption/power loss

Current consumption from backplane bus35 mA
Power loss5 W

Technical data digital inputs

Number of inputs16
Cable length, shielded1000 m
Cable length, unshielded600 m
Rated load voltageAC 120/230 V
Current consumption from load voltage L+ (without load)-
Rated valueAC 120/230 V
Input voltage for signal "0"AC 0...40 V
Input voltage for signal "1"AC 79...264 V
Input voltage hysteresis-
Signal logic inputSinking input
Frequency range47...63 Hz
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"25 ms
Input delay of "1" to "0"25 ms
Number of simultaneously utilizable inputs horizontal configuration16
Number of simultaneously utilizable inputs vertical configuration16
Input characteristic curve-
Initial data size2 Byte

Status information, alarms, diagnostics

Status displaygreen LED per channel
Process alarmno
Diagnostic interruptno
Diagnostic functionsno
Diagnostics information read-outnone
Supply voltage displaynone
Group error displaynone
Channel error displaynone


Between channels
Between channels of groups to4
Between channels and backplane bus
Insulation tested withDC 4000 V


Input bytes2
Output bytes0
Parameter bytes0
Diagnostic bytes0


MountingRail System 300

Mechanical data

Dimensions (WxHxD)40 mm x 125 mm x 120 mm
Net weight240 g
Weight including accessories-
Gross weight-

Environmental conditions

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


UL certificationyes
KC certificationyes