12
Configuration
- Ki:
Integral PI adjustment. This parameter acts on the accumulated error and enables reading stabilisation
once the setpoint value has been achieved. It is only valid for in-line controls. For recirculating controls it
must be Ki=0.
- T delay (seconds):
T delay is the time between two consecutive controller orders to position the regulating output. For a
proper regulation, this time has to be greater than it takes fro a drop of dosed product to travel from the
injection point to the point where the pH or EC sensor is located.
- Q test:
Reference flow rate for T delay that allows for automatic adjustment of T delay with changes in water flow
rate, so that T delay is always at an optimal value. To keep T delay fixed, leave Qtest = 0.
Example: In a 8" pipe through which water passes at 100 m3/h, the water speed is approximately 1 m/s.
If the distance between the injection point and the sensor is 10 metres, the installation delay time is 10
seconds.
The sensor will have a reaction time (approximately 10 seconds for the pH sensor), which must be added
to the installation delay time. Therefore, a T delay = 20 seconds should be set.
Bear in mind that if there are any filters between the injection point and the sensor, the calculation of 10
metres x 1m/s = 10 seconds will no longer be valid.
4.5 Alarms
4.5.1 EC and pH alarms
To set the alarms, enter the upper and lower tolerance values with respect to the value entered as the
setpoint and the time from which, with the reading outside tolerance range, the alarm must be activated. If
the value = 0, the alarm is disabled. The alarms will activate only if the Control is ON.
T delay
Injection
point
Sensor
m/s
Summary of Contents for WTRTEC Green
Page 1: ...WTRTEC ENGLISH...
