Specifications

ST900 Family General Handbook
667/HB/32900/000 Issue 11 Page 224 of 265
 Instigation of Flash Amber Mode due to Fault
 Holding a stage with a Special Conditioning timer
31.4 Reading Controller Timers
It is possible to read whether certain controller timers are active, held or expired,
and also what the count value is. Following is a list of timers that have the above
facility:
Minimum Green Call/Cancel
Green Extension Priority Extension
Maximum Green Priority Maximum
Phase Delay Priority Inhibit
Lamp Sequence, such as R/A, ped clearance
Compensation
Inter-green Fixed Time
Hurry Delay Window Times
Hurry Hold Hold Inter-green Maximum
Hurry Prevent Hold Inter-green Extension
Conditioning
Note the timers cannot be loaded with a value in conditioning and the actual count
value cannot be read. Only logical expressions can be performed, i.e. count equal to
‘x’ or count greater than ‘x’.
Example
If a side road phase is extending towards its maximum and a demand is inserted for
the main road, providing the side road max timer has exceeded 20 seconds, the
extensions may be prevented, to allow the main road phase to gain ROW
immediately.
Phase B at green and demand present for phase A?
YES NO
Phase B max timer > 20? Do nothing
YES NO
Prevent phase B
extensions
Allow phase B
extensions
END
MAIN ROAD = PHASE A
SIDE ROAD = PHASE B
31.5 Special Conditioning Libraries
Within the controller configuring system (The IC4 Configurator), files containing
special conditioning code can be stored and used as a library. These allow
commonly used items of special conditioning to be recalled for use at any time. For
further details see the Configurator Handbook.