Honeywell 900U02-0100 User And Installation Manual page 181

Cold Start
A Cold Start clears the data in battery backed RAM, turns all outputs off, transfers the configuration file
from flash memory to RAM and reinitializes all dynamic data.
The Cold Start procedure is flowcharted in Figure 96. The controller initiates the Cold Start procedure:

After a power outage, when diagnostics indicate that the controller hardware and software
program are intact, but the content of the RAM database is incorrect. (See Figure 95.)

On a Mode transition from PROGRAM to RUN. (This Mode transition can be initiated by
operating the Mode switch on the controller or RSM, or by exiting the Program mode at a
Control Station.)

When initiated by the user (after download with Cold Start selected, or any transition from
PROGAM Mode to RUN Mode.)
CAUTION
During controller restart (during cold start or hot insertion of controller/scanner) local IO module
will get reset and all outputs will go to un-power state regardless of configured failsafe state.
Revision 10 ControlEdge HC900 Process & Safety Controller User and Installation Manual
May 2019
Figure 96 – Cold Start Operation
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