Introducing the Absolute Encoder Module
Chap
t
er 2
2Ć2
You can use the absolute encoder module with any Allen-Bradley
programmable controller that uses block-transfer programming in both
local and remote 1771 I/O systems. Processors that are compatible with
the module include:
Mini PLC-2 (cat. no. 1772-LN3)
PLC-2/20 (cat. no. 1772-LP1, -LP2)
PLC-2/30 (cat. no. 1772-LP3)
PLC-3 (cat. no. 1775-L1, -L2)
Mini-PLC-2/15 (cat. no. 1772-LV)
Mini-PLC-2/05 (cat. no. 1772-LS, -LSP)
You can use Allen-Bradley absolute encoders that use up to 12 bits with
the absolute encoder module. Allen-Bradley encoders with the following
bulletin numbers are compatible with the absolute encoder module:
Bulletin 845A
Bulletin 845B
Bulletin 845C
The module is also compatible with absolute encoders that have the
following specifications:
single-ended or differential encoder output signals
TTL-compatibility (output drivers)
capability of sinking 11mA (single-ended) or 18mA (differential) per
channel
BCD, natural binary, or standard Gray code format
You can select the state in which the outputs will be if the module loses
input power. A configuration plug on the right printed-circuit board
allows the outputs to:
turn off
remain in their state at loss of input power
Compa
t
ible Processors
Compa
t
ible Encoders
S
t
a
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e o
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Ou
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s Upon Loss o
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Inpu
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Power
