30 C4 Manual Rev 7.5.2
3.5 System Operating (Temperature) Range
The C4 controller operates within the limits of the system devices. There are 3
pairs (low-high) of temperature limits that constrain the range of operations.
1. The range of the C4 as it is set at the factory
2 The range of the controlled device (chamber or platform) as
described by setup parameters F25 & F26.
3 The range of the UUT (unit under test) as described by
setup parameters F27 & F28.
Each of these ranges is characterized by a low limit and a high limit. The highest
of the 3 low limits is the low temperature System Operation Limit. The lowest
of the 3 high limits is the high temperature System Operation Limit. In other
words, the controller will respect the most restrictive limits that are described by
the combination of the 3 ranges listed above.
The low and high temperature System Operating Limits define the System
Operating Range. The controller will not accept setpoints outside the System
Operating Range and will report error conditions and stop controlling if the
controlling probe(s) report a temperature too far outside that range.
Note: Probe 1 is always in the chamber airstream or platform and is always
monitored for conformance with the System Operating Range. Probe 2 is
monitored for conformance only if it is being used for control.
3.6 Probe Out of Range Shutdown
When the C4 is actively controlling the temperature of a chamber or platform, it
frequently checks to be certain that the control temperature, as reported by any
active control probe, is within the System Operating Range.
In the event that the temperature reported by the active control probe is more
than 20/C, and less than 50/C, outside the controller’s System Operating Range,
then the controller will presume that a “run away” condition exists. The controller
will turn off all heating and cooling and stop controlling. Blowers will be left in
the condition determined by setup parameter F15 (Blower shut-off mode). The
controller display will show
p1 lo p1 hi