Hi guys,
I've come across an some application, but not too sure what is the suitable method to use.
Scenario 1
I'd like to control/maintain the flow in a pipeline. There is a flow meter (4-20mA) & a pump control by inverter (4-20mA). When we set the pipeline flow to (for example) 50 liter/hour, the pump must run 50%, when we set the pipeline to 80 l/h, the pump must run 80% automatically. For this scenario, it's more suitbale to use a PID or use some SCL/SCP instructions?
Current system design: They manually set the pump to run and monitor the flow (l/hr) at the RSView32.
Scenario 2
To control the temperature of a tank. There is a hot water pipeline feeding hot water into the tank, if we set 500 deg C for the tank, a control valve will open (for example) 50% to allow the hot water to flow into the tank. Once the tank reached the setpoint temperature, i'll close the control valve. When the tank temperature starts to drop, the control valve will open slighlty to allow the hot water to flow into the tank automatically. For this scenario, it's more suitbale to use a PID or use some SCL/SCP instructions?
Current system design: The system is using a digital valve (open or close), so the temperature in the tank will tend to overshoot/undershoot a lot (sometimes until temp high/low alarm is activated and shutdown their system).
Hope to hear from you guys who is more experience.
I've come across an some application, but not too sure what is the suitable method to use.
Scenario 1
I'd like to control/maintain the flow in a pipeline. There is a flow meter (4-20mA) & a pump control by inverter (4-20mA). When we set the pipeline flow to (for example) 50 liter/hour, the pump must run 50%, when we set the pipeline to 80 l/h, the pump must run 80% automatically. For this scenario, it's more suitbale to use a PID or use some SCL/SCP instructions?
Current system design: They manually set the pump to run and monitor the flow (l/hr) at the RSView32.
Scenario 2
To control the temperature of a tank. There is a hot water pipeline feeding hot water into the tank, if we set 500 deg C for the tank, a control valve will open (for example) 50% to allow the hot water to flow into the tank. Once the tank reached the setpoint temperature, i'll close the control valve. When the tank temperature starts to drop, the control valve will open slighlty to allow the hot water to flow into the tank automatically. For this scenario, it's more suitbale to use a PID or use some SCL/SCP instructions?
Current system design: The system is using a digital valve (open or close), so the temperature in the tank will tend to overshoot/undershoot a lot (sometimes until temp high/low alarm is activated and shutdown their system).
Hope to hear from you guys who is more experience.