Rockwell Automation 1771-IJ_IK IK ENCODER/COUNTER MODULES User Manual

Page 10

1–2

Introduction

Publication 1771ĆUM006B-EN-P - June 2002

Figure 1.1

Encoder Counter Module (cat. no. 1771ĆIJ/IK)

Slotted for I/O

Insertion Only

Protective Cover

Label Identifies User

Output Connections

Brown

Identification

Label

Field Wiring Arm

Connects Here

Status

indicators

15942

The module will count in either BCD or binary numbers. In the
BCD mode, the range is 000 to 999 with carry and borrow bits
provided to cascade counters in the program. The binary mode
allows a higher count total, with a range of 0000 to 4095

, but the

number appears at the processor in binary. Additionally, the module
can improve the accuracy of certain quadrature type of encoders by
adding the count at both channel A and channel B (times 2 mode), or
by counting the rising and falling of both channel inputs to give a
fourfold increase in the count (times 4 mode).

The encoder/counter module is available in two versions:

•

cat. no. 1771-IJ - uses a 5V dc external power supply that allows
inputs to be TTL compatible. Outputs can either be driven from
the 5V dc supply through the module or from a separate load
supply of a different voltage.

•

cat. no. 1771-IK - uses a 12-24V dc external power supply. Input
devices should be compatible with the voltage of the external
power supply. Outputs can be driven either from the external
supply through the module or from a separate load supply.