model 2704 controller installation and operation handbook - Soliton

Totaliser, Timer. Clock, Counter Operation
2704 Controller
12.2.3. One Shot Timer Mode
This timer behaves like a simple oven timer.
• When the Time is edited to a non-zero value the Output is set to On
• The Time value is decremented until it reaches zero. The Output is then cleared to Off
• The Time value can be edited at any point to increase or decrease the duration of the On
time
• Once set to zero, the Time is not reset to a previous value, it must be edited by the
operator to start the next On-Time
• The Input is used to gate the Output. If the Input is set, the time will count down to zero.
If the Input is cleared to Off, then the Time will hold and the Output will switch Off until
the Input is next set.
Note: since the Input is a digital wire, it is possible for the operator to NOT wire it, and
set the Input value to On which permanently enables the timer.
• The Triggered variable will be set to On as soon as the Time is edited. It will reset when
the Output is cleared to Off.
Figure 12.3 illustrates the behaviour of the timer under different input conditions.
Input
Time Edited
Time Edited
Output
Time
Time
Time
Elapsed Time
Triggered
This diagram shows how the Input can be used to gate the Timer as a type of hold
Input
Output
Time Edited
A
B
C
D
A+B+C+D =
Figure 12-3: One Shot Timer
12-6 Installation and Operation Handbook. Part No HA026502 Issue 1.0 Apr-00