Parameter setting and wiring of the inverter in different operating modes - Database & Sql Blog Articles

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There are many operating modes of the inverter, and its parameters are also very many. In order to make the inverter run efficiently and serve us better, we must select a suitable operating mode according to our actual situation and control requirements. Our company has a number of inverters produced by different companies, such as: Fuji, Siemens, Mitsubishi, Panasonic, etc. According to the experience in the work, I found that although their shapes vary widely, the control methods are similar. Let's take Fuji's FRN0.4~220G11S-4CX series inverter as an example to talk about its operation mode.
In order to make the inverter run, one must have a start signal, and the other must have a speed signal. Both are indispensable. According to whether the signal is taken from the outside of the inverter or from itself, it can be divided into the following three types:
1. E mode: the signal is taken from the outside of the inverter;
2. PU mode: the signal is taken from the inverter itself;
3. PU+E mode: The signal is both external to the inverter and the inverter itself.
In the PU mode, the operation is performed through the panel of the inverter. Use the ∧ and ∨ keys to set the frequency, press the FWD key to rotate the motor forward, press the REV key to rotate the motor in reverse, and press the STOP key to decelerate to stop. In the operation, use the ∧ and ∨ keys to change the frequency to achieve the purpose of changing the speed. This method is very effective when the wiring is completed and commissioned, but it is not commonly used in normal work, because its signal is not controlled by us, it is given by the inverter itself.
In PU+E mode, if the start signal is given by the panel's FWD button, REV button and STOP button, the frequency setting signal is from the outside. This mode is not very meaningful in actual operation because each run and It is extremely inconvenient to open the electrical control cabinet and press the corresponding button on the panel. If the speed is not frequently switched during normal operation, we can control it like this: the start signal is given by the external switch contact or control system. Press ∧, ∨ keys to enter the digital frequency setting, set a suitable frequency to store, and then run at that speed every time after running. When you need to change the speed, press ∧, ∨ keys to increase or decrease the speed. In this mode, there are two parameters that are critical: parameter F01 (ie frequency setting mode) is set to 0 (ie set by the panel's FWD key, REV key); parameter F02 (running mode) is set to 1 (Through the external terminals [FWD], [REV] as the start signal), in fact, the E mode is commonly used in practical work. The following discussion focuses on this mode. In this mode, a number of subclasses can be separated depending on the signal mode of the speed adjustment. These speed adjustment signals can be either voltage or current, or can be a switching signal, a digital input, or a pulse train input. The following description will be combined with different settings of the parameters and hardware wiring.
The speed adjustment signal is analog voltage and is input from the inverter's 12th terminal. The voltage can be 0 to +10V, or it can be -10V to +10V. The former parameter F01 is set to 1, and the latter is set to 4. In addition, if reverse action is required, that is, +10V corresponds to low speed, 0V corresponds to high speed, and F01 needs to be set to 6.
The speed adjustment signal is analog current and is input from the C1 terminal of the inverter. The current signal is 4 to 20 mA. When the forward motion is required, the parameter F01 is set to 2; when the reverse motion is set to 7. Sometimes, the voltage signal and the current signal can be combined to control the set frequency, that is, the sum of the No. 12 terminal + C1 terminal is used as the set value. At this time, parameter F01 is set to 3. Note the effects of parameters F17 and F18 in the above two modes. F17 is the frequency gain and F18 is the frequency offset.
The speed adjustment signal uses a combination of external switch signals. The inverter has nine contact input terminals that can be freely defined by parameters. The parameters E01, E02, E03, and E04 are defined as 0, 1, 2, and 3 respectively, and the contact inputs X1, X2, X3, and X4 are assigned as switch signals SS1, SS2, SS4, and SS8, which have 24=16 combinations. There are 15 kinds of combinations that are all zero, so that 15 speeds can be set.
A potentiometer is connected between the terminals of terminals 11, 12 and 13 of the inverter. With the internal 24VDC power supply, the speed can be continuously adjusted, and the potentiometer can be mounted on the control panel, which is very convenient.
Using the ∧ and ∨ keys of the panel, the frequency can be changed quickly and easily. In fact, by parameter definition, we can bring these two signals to the terminals of the inverter. We define the parameters E05=17, E06=18, so that the contact input terminals X5 and X6 are assigned as the speed increase command (UP) and the deceleration command (DOWN). Of course, we can define any terminal between X1 and X9 as UP or DOWN. Then set the parameter F01 to 8 (acceleration/deceleration mode 1) or 9 (acceleration/deceleration mode 2). In this way, the motor is lifted and lowered by jogging the button connected to X5 and X6.
In the above various control modes of E mode, the control signals are weak analog signals, which are easily subject to external interference, and the inverter itself is a large noise source. It is necessary to strengthen anti-interference measures. The following measures are necessary. It is worth considering:
1. The control line is as short as possible, and the shielded wire is used, paying attention to good grounding;
2. Use a twin contact that handles weak signals;
3. A capacitor and a ferrite core are connected to the analog signal device side.
Mastering the various operating modes of the inverter is of great benefit to us in selecting the appropriate working mode of the inverter, and also helps us to take the work to a new level.