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7 Component Communications
E5@C Digital Temperature Controllers Communications Manual (H175)
7-3 Troubleshooting
7
7-3 Troubleshooting
Possible problems that can occur with component communications and corrective actions are given in
the following table.
Note: For information on other problems, refer to A-2 Troubleshooting.
Status Cause and corrective action Page
The set point or RUN/STOP status
will not change for a slave (i.e., a
Controller with a communications
unit number other than 0).
The wiring to the slave is not correct. 7-2
The communications settings for the slave are not
correct.
• The Protocol Setting parameter is not set to cmp.
• The Communications Unit No. parameter is set to
the same value as another slave.
• The setting of the Communications Baud Rate
parameter is not the same as the other slaves.
• The Highest Communications Unit No. parameter
is not set to the highest communications unit
number that is actually set.
• The Communications Writing parameter is set to
OFF.
7-3
When the RUN/STOP Does Not Change
RUN/STOP is assigned to an event input for the
slave.
7-6
When the Set Point Does Not Change
The set point from the master or the results of set
point calculations exceeds the set point limiter of the
slave.
7-5
7-6
The set points or the RUN/STOP
status will not change for any of the
slaves.
The wiring to the master (i.e., the Controller with
communications unit number 0) is not correct.
7-2
The communications settings in the master are not
correct.
• The Protocol Setting parameter is not set to cmp.
• The Communications Unit No. parameter is not set
to 0.
• The Communications Baud Rate parameter is not
set to the same value as the slaves.
• The Highest Communications Unit No. parameter
is not set to the highest communications unit
number that is actually set.
7-3
The set point is not calculated. • The SP Slope or SP Offset parameter is not set
correctly.
• The set point was changed at the master when the
slave was stopped (setting area 1).
7-5
It is sometimes not possible to
change the set points or
RUN/STOP status.
There may be noise interference. Connect
terminating resistance to both ends of the
communications line.
7-2