Through the PFC1020 built-in "microcontrol CPU" to prevent rapid increase in the pressure within the tube, effectively achieve constant pressure quantitative, fixed speed
The function is applicable to control equipment such as water supply, air conditioning, and flow. Strong function, high efficiency, high precision, turn ratio and position
Signal conversion function.
Function and control: This unit is based on the pressure change detected by the pressure sensor on the pipeline, through the calculation of the microcomputer constant voltage controller with the micro-control CPU, and the sensing signal value and the set value are displayed in the position of the second position (small position). After comparing and calculating, the output DC 0~10V turns ratio signal to the inverter, and the inverter changes the running frequency according to this DC 0~10V change, and then the pump motor changes the rotation speed with the change of frequency to achieve constant. Pressure function.
1. Pressure adjustment: According to the performance of the pump and the water pressure demand, coordinate with the set key in the touch mode, and the set value at the same time is displayed on the screen (the second bit of the small defect).
2. No water stop: The pressure of the pipeline detected by the pressure sensor changes, and the state of the pressure is displayed on another screen (the second bit of the small fault). If the pressure of the pipeline is greater than or equal to that of the constant pressure controller, When the pressure is set, it enters the stop frequency range and continues to detect for 20 seconds. In this case, if no water is used, the PFC1020 will send a stop command and the inverter output frequency will start to decrease until the operation stops. It can be freely adjusted (usually set for 15 seconds) to achieve the purpose of buffer stop, avoiding the impact of water hammer, and the pressure after stopping is stable to ±5% of the set pressure.
3. Operation with water: In case of water use, PFC1020 contains PID auto-calculation, compares the pressure change with the set value, and outputs the appropriate DC 0~10V turn ratio signal to reach the constant pressure, if it is in the stop condition, When the water pressure is lower than a certain percentage of the set pressure, the PFC1020 commands the inverter to start and drive the pump motor to avoid frequent start-up. The above percentage is 0 to 100% free adjustment.
4. Water leakage detection stop compensation function: In the case of very small water consumption, such as pipe leakage and drip conditions lead to pressure drop, then PFC1020 will command the pump motor to stop running (this off pressure change range is adjustable from 0 to 0.6kg), If the pressure continues to drop to a certain percentage of the set value, the PFC1020 will command the pump motor to start and make up the pressure to the set value. A certain percentage of this segment is still 0~100% adjustable.
5. Loss of water and voltage loss protection function: When the pump is running at full speed, but it has not been able to reach the set value, if 20 seconds after the point of failure, PFC1020 will interrupt the output to stop the pump motor, and the fault light is on (the fault is The setting value of 0~100% can be adjusted.) After confirming the reason and eliminating the reason, press the RESTE button or restart the operation.
6. Constant pressure setting: Simply press the increase key or decrement key on the PFC1020 panel to set the desired pressure, which is easy to operate. After the pressure is set, the water pressure does not dip or use water, and the line pressure is stable at ±5% of the set value.
7. Pressure alarm output: Alarm1, Alarm2, 2 alarm output points can be used for alarm application.
8. Alternating parallel control:
(1) Parallel mode: In the micro-control CPU control mode, the first operation starts with a single unit. If a single unit is not enough to meet the water demand, the first machine to run will run at 100% full speed, and then start another parallel system. The juxtaposition machine meets the constant pressure demand by means of frequency conversion, and the unit is operated in the best state, effectively preventing back pressure from being generated.
(2) Alternating operation: 2 pumps are assigned to the lead pump according to the task, and the supporting pump is only added when the parallel operation is performed. However, after each alternate time, the original lead pump becomes the branch pump and the branch pump performs the pilot. The mission of the pump, this alternating time now needs to be adjustable 0~24 hours.
(3) Separate operation: It is also possible to select a single fixed operation without alternate operation.
(4) Failure replacement: If the guide pump malfunctions before operation, the guide pump will immediately switch off.
(5) Machine operation change: When no operation is performed alternately or side-by-side, or when the fault is replaced, the pump motors are all connected smoothly and the pressure in the pipeline is not changed.
※ How to calculate the dehydration, pressure loss failure pressure point, and ABNP set value?
(1) (SV) × (ABNP) = pressure point for water loss and pressure failure, SV = 2.0kg, ABNP = 70% = 0.7
2.0 × 0.7 = 1.4kg is the pressure point for loss of water and pressure.
(2) If the minimum political pressure at the site is 0.59kg, how much should the failure pressure point be set?
(minimum normal pressure value) × (SV) = What is the minimum normal pressure value in percent of the set value?
0.59kg ÷ 2.0 = 0.295 = 29.5% is the minimum normal pressure value,
So the fault pressure point should be set lower than 29.5%, so the set value should be 25%.