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Programmable Relay: Difference between ZEN's 8E1 and 4E/8E Expansion I/O Units

FAQ No. FAQ04287

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ZEN Programmable Relays: What is the difference between 8E1 and 4E/8E Expansion I/O Units?


ItemZEN-8E1[]ZEN-4E[] and ZEN-8E[]
Type8 inputs/outputs4 inputs, 4 outputs, and 8 inputs/outputs
ShapeWidth: 35 mm, no heat dissipation slitsWidth: 70 mm
Screw mounting methodM3 (mounting holes on DIN Track)M4 (holes on Expansion I/O Units)
Power supplyZEN-8E1AR, -8E1DR: Required.
ZEN-8E1DT: Not required.
Not required.
AC input
Input impedance680 kΩ83 kΩ
Isolation methodNot isolatedPhotocoupler
Input commonConnected internally to power supply terminal.Separated as COM terminal.
DC input
Input voltage10.8 to 28.8 VDC20.4 to 26.4 VDC
ON voltage8 V16 V
Input impedance6.5 kΩ4.7 kΩ
Isolation methodZEN-8E1DR: Not isolated
ZEN-8E1DT: Photocoupler
Input commonZEN-8E1DR: Connected internally to power supply terminal.
ZEN-8E1DT: Separated as COM terminal.
Separated as COM terminal.
Contact current for Models
with Relay Outputs
8 A/contact
The total for all outputs must be as follows for each Unit: 20 A
8 A/contact
Maximum voltage for Models
with Transistor Outputs
28.8 VDC26.4 VDC
Connectable CPU UnitsV2 CPU UnitsV1 and Pre-V1 CPU Units