Before You Begin; Understand Short Circuit Detection - Allen-Bradley POINT I/O 1734-IB4D Installation Instructions Manual

POINT I/O 24V DC 4-channel Discrete Input Module with Diagnostics
POINT I/O Input Module with 1734-TOP or 1734-TOPS Base
Module locking
mechanism
Module wiring diagram
DIN Rail locking
screw (orange)
Mechanical
Keying (orange)
Interlocking
side pieces

Before You Begin

The module supports remove and insert under power, auto-address, and auto-baud in
compliance with the POINTBus™ backplane. Each input is a sinking DC input with short
circuit and open-wire detection. The sensor source voltage is derived from the user
auxiliary power and used as I/O power.

Understand Short Circuit Detection

The sensor source voltage (SSV) for each input is protected against short circuits. For
currents above 200 mA, a fault signal is issued and the input LED indicator is illuminated
solid red. A thermally actuated smart-power device or PTC is used as the protection
means. On a per-input basis, the circuit and produced data automatically reset and SSV
energizes upon removal of the short circuit. An individual fault signal is issued for each
shorted SSV condition.
The shorted input LED indicator illuminates red to denote short circuit fault status.
See the section on interpreting LED indicators for related information.
Slide-in writable label
Publication 1734-IN029B-EN-E - July 2018
Insertable
I/O module
Handle
One-piece
terminal
base with
screw or
spring
clamp
44221
7