Soak And Event Timers - Extech Instruments 48VTR User Manual

Soak and Event Timers

The Alarm Relays can be used as Soak timers or Event timers as detailed below and in the
Appendices.
A Soak timer starts counting when the PV reaches the SV and switches the alarm relay ON.
When the timer stops, the alarm relay switches OFF.
An Event timer starts counting when the PV reaches SV also but does not switch the alarm
relay ON yet. The alarm relay switches ON only after the timer stops.
Soak Timer
The Soak Timer starts counting when the control setpoint (SV) is reached and stops counting
after a programmed time value. The alarm relay switches ON when the timer starts and
switches OFF when the timer stops, allowing a 'Soak' at a desired process point for a
programmed time value.
1. Set the 'A1Fu' parameter to either '10' (Soak ON-Timer) or '11' (Soak OFF-Timer); On-
timers start from an energized state and change to a de-energized state at the switch
points. Off-timers start from a de-energized state and change to an energized state at
the switch points. Refer to the Appendices for more information.
2. Set the Soak time in parameter 'timE' in the 1
3. The ALM status LED flashes while the timer is counting and stops flashing when the
timer stops.
4. In the diagram below, the Alarm relay is available on terminals 4 and 5, the control
relay on terminals 8 and 9, and the AC power on 6 and 7. In this example, the Alarm
relay switches power to the Control relay ON and OFF allowing the Soak timer to
control the process unhindered for the programmed Soak time.
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Menu.
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48VTR User Manual v6.0 10/1/20