Thermcraft XST-6-0-36-3V - Manual (Page 88)

Programmer Operation Installation and Operation Handbook
5-4 2408 and 2404 Controller
PROGRAMMER STATES
The programs have five states: Reset, Run, Hold, Holdback and End.
State Description Indication
Reset In Reset, the programmer is inactive and the
controller behaves as a standard controller, with the
setpoint determined by the value set in the lower
readout. Both the RUN and
HOLD lights are OFF
Run In Run, the programmer varies the setpoint
according to the active program. RUN light on
Hold In Hold, the program is frozen at its current point. In
this state you can make temporary changes to any
program parameter (for example, a target setpoint, a
dwell time, or the time remaining in the current
segment). Such changes will only remain
effective until the program is reset and run
again, when they will be overwritten by the
stored program values.
Note: When a program is running, you cannot alter
a
cALLed program until it becomes active within
that program.
HOLD light on
Holdback Holdback indicates that the measured value is
lagging the setpoint by more than a preset amount
and that the program is in Hold, waiting for the
process to catch up. See Holdback in the section
on Automatic behaviour later this chapter. HOLD light flashes
A master controller can re-transmit a setpoint value
to a number of slave units using PDSIO setpoint
retransmission. Any of the slave units can generate
a holdback signal which will also flash the HOLD
light. Holdback will also occur if the PDSIO output is
open circuit. This can be disabled in configuration
by selecting the
PdS output as SP.nH - ‘setpoint
retransmission without holdback’
HOLD light flashes
End The program is complete. RUN light flashes
Table 5-2 Program States