How can I use a ABB converter and a pressure sensor to be a constant pressure water supply system?
The signal terminal is arranged in an independent cabin of the electric box. When connecting, unscrew the watch cover on the wiring side. The above is the terminal signal terminals, the terminal is connected to the terminal indicator (see below). The current on the terminal below is the same as the current on the signal terminal. It is 4-2OmADC. It can be used to connect the indicator. The power supply is connected to the transmitter through the signal wire, and no additional wiring is required.Shielded wire is preferred for signal line. The signal line shall not pass through the metal tube with other power lines, or in the same line slot, nor through the vicinity of the strong current.The threading holes on the electrical housing of the transmitter shall be sealed or plugged (with sealant) to prevent moisture accumulation in the electrical housing. If the threading hole is not sealed, the threading hole should be made downward so that the liquid can be easily removed when the delivery device is installed.The signal line may be floating or in the signal loop in any one point grounding, the transmitter housing can be grounded or ungrounded. The power supply does not have to be regulated. Even if the supply voltage fluctuates lV, the influence on the output signal is almost negligible.Because the transmitter is connected to the ground through the capacitor, it is not possible to use a high impedance meter higher than 1OOV when checking the insulation resistance. The circuit shall check for voltage not greater than 1OOV.The maximum output current of the transmitter shall not exceed 3OmADC
closed loop control system4 to 20mA sensor feedback signal connected to the inverter, frequency given channel selection is set to VCI (don't know the ABB converter is not the same set of Kazakhstan, the truth), according to the change of pressure sensor of converter can adjust the frequency of the output feedback signal can be automatically made of a constant pressure water supply system.
The scene using 3 ABB inverter induction motor, a DC010V range for remote pressure 1Mpa table, a 010v range potentiometer, a liquid level sensor, pressure signal to set the desired by the potentiometer, the feedback signal to the HD31 the actual pipe network pressure remote pressure gauge, the reservoir water level sensor monitoring information. HD31 information from the liquid level sensor determines whether the current system continues pumping water from the reservoir. When the reservoir is full of water, the ABB converter operates the potentiometer signal and the remote pressure meter signal through the built-in PID function to achieve the desired pipe network pressure.Adjustment method:(1) wiring in accordance with the above;(2) enabling the water supply expansion function and enabling the water supply expansion card;(3) setting the rated current of water pump 1 according to the motor nameplate;(4) set the command given channel;(5) setting acceleration and deceleration time, analog function and terminal function;(6) ABB frequency converter adjusts two analog signals, and adjusts PID parameters according to actual performance.Adjusted effect:Set the desired network pressure after the start of constant pressure water supply system, through the PID function pump built-in HD31 1 soon change from 0Hz to PID at the upper frequency of operation, has not reached the expected network pressure, more than the pump detection time after the inverter according to the deceleration time preset immediately by the PID on frequency is reduced to a lower frequency, ABB converter at the same time to pump 2 frequency mode is put into use, and then pump 1 again according to PID regulation of the frequency of operation, the observation signal remote pressure gauge feedback stable pressure in the pipe network within the scope of our set in advance.
