Operation For Component Communications - Omron E5C-T Series Communications Manual

7 Component Communications
7-2 Operation for Component
Communications
Only two items can be sent from the master to the slaves: the fixed SP or program SP, and the
RUN/RESET status.
If the set point or the RUN/RESET status is changed at the master, the new value is sent to the slaves
starting with the slave with communications unit number 1 and continuing on to the slave with the high-
est communications unit number. The master sends values only during operation. Values are not sent
while in the initial setting level.
If the RUN/RESET status is changed again while sending a previous value to the slaves, the original
value will not be transferred correctly. Always wait for a value to be sent to all of the slaves before you
change the RUN/RESET status again.
Operation level, program setting level, adjustment level, PID
setting level, manual control level, monitor/setting item level,
and protect level
Initial setting level, communications setting level, advanced
function setting level, and calibration level
For component communications, the master sends the value in order starting from slave 1. There will
be a delay of up to 30 ms between when the set point or RUN/RESET status is sent to all of the slaves.
However, in a control system with a fast response, the slaves may not be able to response as quickly as
the master. If you transfer the program SP with component communications, be prepared for a delay in
operation due to a difference in timing.
If communications with a slave fail, the master will retry communications twice. If communications still
fail, it will move to processing the next slave. To see if the value was sent correctly, check the display of
the Set Point or STOP parameter on each slave.
 Exception Processing
Slaves
7 - 6
Levels
• SPs are not calculated when operation is stopped.
• The value from the master is not received in the following cases.
• When the set point from the master or the results of set point calculation exceeds the set
point limiter of the slave.
• When Communications Writing parameter is set to "OFF"
• When RUN/RESET is assigned to an event input (Changes in the set point will be
received.)
• When a communications error occurs three times in a row
E5C-T Digital Temperature Controllers Programmable Type Communications Manual (H186)
Component
communications
Setting area 0 Operates
Setting area 1 Stops