Inverter fan pump control program in the pump application

1. Senlan pump with frequency converter performance profile

(1) BT12S series inverter

Senlan BT12S series of frequency converter, is the company for fans, pumps and mechanical design of a dedicated digital converter, in addition to a common inverter function, there are variable frequency pump cycle, variable frequency pump fixed two ways of timing rotation function (Access relay expansion board can be realized, see instructions).

The PI regulator is equipped in the inverter. There are two sensor feedback signal input terminals, VPF (voltage signal) and IPF (current signal), as well as the fire operation signal terminal FA, the high water level signal terminal LA2 and the low water level terminal LA1, Upper and lower alarm output terminals 30PA, 30PB and 30PC.

BT12S series inverters have unique settings of sleep value and wake value (parameters F66 and F67). When the water supply system has two or more pumps, according to user requirements set the appropriate sleep value and wake value. When the pressure is lower than the sleep value, the pump works; when the pressure is lower than the awakening value, the main pump works; on the contrary, when the pressure is higher than the awakening value, the main pump stops working and the small pump works; when the pressure is higher than the sleep value, The pump also stopped working and went to sleep.

Senlan BT12S series inverter can also be used as a universal frequency converter.

(2) SB60P and SB61P series inverter

The two Senlan inverter circuit structure is the same, but different capacity range. Are using digital processor DSP vector control inverter, better performance. Inverter equipped with PID regulator, but also an external expansion board for multi-pump cycle.

2. Fan pump frequency control program

There are many kinds of control methods for fan pumps, which can be selected according to specific situations. Here are some commonly used programs.

(1) manual adjustment

This is one of the easiest methods of control, in which the operator manually adjusts the frequency of the frequency converter to change the air volume or flow to meet the production requirements based on the instrumentation instructions. This method is suitable for any type of frequency converter, commonly used in the technical transformation of old equipment. FWD is the forward signal input terminal, CM is the common terminal of input signal, SB is the changeover switch. When SB is closed, motor M is started in the forward direction; when SB is off, the motor is stopped. To retain the original device starting device, the baffle, the valve completely open, usually make KM1, KM3 connected, the use of inverter drive. If the frequency converter malfunctions or needs the overhaul, then disconnect KM3, make KM2 turn on, adopt original equipment starting device and flapper valve to operate. In order to ensure safety, KM2 and KM3 two contactors to interlock (including electrical and mechanical interlocking).

(2) double-frequency control inverter

This method is simple, reliable, easy to grasp, the accuracy can basically meet the requirements, is widely used in many less demanding field.

X4 and X5 two terminals, according to the inverter manual according to its provisions for the appropriate preset, it has the function of controlling the inverter speed and deceleration. SP for the electrical contact pressure gauge, SP1 and SP2, respectively, the pressure of the lower limit contacts and the upper limit contacts. Direct control of the state of X4 and X5. That is, when X4 is connected to CM, the output frequency fx of the inverter rises and stops rising when it is disconnected. When X5 and CM connected, fx down, fx stop falling off.