Siemens SIMATIC 505 User Manual

Troubleshooting

Series 505 High Speed Counter 
and Encoder Module User

’s Manual

Troubleshooting

Re-seat board

Check jumper position
and condition of jumper (metal insert intact)

Input LED is
not on
and 
Output LED is
not on

Signal wire noise

Module not configured
in controller I/O 
configuration table

Module configured 
incorrectly in controller

Module has failed 
self-diagnostics

Nonfatal error
as a result of the
module

See wiring considerations ( Section 2.1.4)

Configure module

Return module for repair

Reconfigure the module

Check your base power supply

Check wiring

Check encoder or field inputs

Incorrect count

Connections wrong

Counts in wrong
direction

Connections wrong

Counts erratically

Wrong quadrature mode
or 2 jumpers on same chan-
nel

Pulse too narrow, or
frequency too high

Use slower gear ratio and 
higher resolution count

Reverse wiring for inputs A and B

Trace wiring connections

Counts too fast
or too slow

Check quadrature mode

Check signal wire noise

Marginal input signal

Does not count

Count being reset or in-
hibited

Check Reset and Inhibit signals from field

Controller does 
not communicate
with module

Broken wire

Check continuity

Broken wire

Check continuity

Broken wire

Check continuity

Input wires substantially
different lengths

Check that wires are as short as possible, and make
wires the same length (if possible)

Input wires substantially
different lengths

Check Reset and Inhibit bits in Setup word (WY4)

Check for bent pins on board connector

No power to board

Problems with input 
signals, or output being
reset or inhibited

Check that wires are as short as possible, and make
wires the same length (if possible)

Check Reset and Inhibit bits in Setup word (WY4)