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C4 Manual Rev 7.5.2
Autostart is enabled, moving the mode from OFF to LOCAL will cause the
controller to begin controlling to the last set local mode setpoint without the
necessity of pressing <START/STOP>. If the system includes mechanical
refrigeration, and the last local control session had the compressor turn on, it will
be turned on for the Autostart session as well.
8.5 Blower Shut-off Mode (Setup field 15)
Normally at the end of a program execution, or in the event of a Fail-Safe
shutdown condition, the blowers in an chamber will continue to run. If this is not
desired, the blowers can be set to shut off under these conditions by enabling the
blower shut-off mode by setting the value of setup parameter F15 to 1. Blower
shut-off mode does not apply to Local mode.
8.6 Temperature Control Terms (PID) (Setup fields 0, 10, 11, 12)
The PID control terms that the C4 uses for temperature control are available in
setup fields 0, 10, and 11. Do not change field 12. If you are not familiar with PID
terms and their effects, a non-theoretical discussion can be found in Section 9.7.7
in the troubleshooting appendix of this manual.
8.7 Software Probe Correction (Calibration)
The C4 will allow you to enter data via Setup or Remote mode that will correct
any anomalies in the temperature readings and control at two points. Such
adjustments are sometimes necessary to optimize accuracy at a particular
temperature, or to compensate for differences between raw probe temperature
data and actual temperatures.
Note: The purpose of this feature is to allow precise calibration at two points near
the critical points of the user’s testing scheme. It does not replace the hardware
calibration process, nor should it. A number of system health checks as well as
process limits are based upon the raw, or uncorrected, temperatures reported by
the probes. It is important to optimize the hardware level calibration before using
this software calibration method.
Software probe correction is achieved by entering four temperatures, U1, C1, U2,
& C2, for each probe into the setup parameter table. U1 & U2 are the
uncorrected, or displayed, temperatures at two points. C1 & C2 are the corrected,
or actual, temperature at those same two points. Thus to make a correction using