Rockwell Automation 900 Temperature Controller Communications Functions - Series B - Manual (Page 38)

Publication 900-UM004D-EN-E - July 2010
2-22 Bulletin 900 Communications Procedures 900-TCx (CompoWay/F)
area 0 and setup area 1. An operation error will occur in the following
situations.
– When AT is being executed.
– When the Multi-SP Uses parameter is set to OFF.
– When the Multi-SP Uses parameter is set to ON but multi-SP is set
for an event input (Number of Multi-SP Uses > 0).
• AT Execute/Cancel
Set AT (auto-tuning) to “execute” or “cancel” with the related
information setting. This command can be accepted in setup area 0 only.
An “operation error” will be generated in the following instances:
– When the RUN/STOP parameter is set to “stop”
– When the command is executed in “setup area 1”
– When ON/OFF control is being used
– When 40% AT is specified during 100% AT execution.
– When 100% AT is specified during 40% AT execution.
In addition, a parameter error will occur if 40% AT is specified during
heating and cooling control.
Note: If the same type of AT execution is specified during AT execution
(e.g., if 100% AT is specified during 100% AT execution), the AT will
not be restarted and the operation will end in normal completion with
no processing.
• Write Mode
Set either the backup mode or RAM write mode with the related
information setting. The setting can be accepted in both setup area 0
and setup area 1.
The number of EEPROM (non-volatile memory) write operations is
limited. Therefore, use RAM write mode when frequently overwriting
data.
Table 2.30
Write Mode Description
Backup mode
The data is written to EEPROM when the parameters in the
operation/adjustment levels (excluding read-only parameters)
are written by communications.
RAM write mode
The data is not written to EEPROM when the parameters in the
operation/adjustment levels (excluding read-only parameters)
are written by communications. Parameters can be changed by
operating the keys on the front panel of the controller.