Application of the hottest ed2003 series frequency

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Application of ed2003 series frequency converter in hoists

the two hoists are mainly used for the adjustment and installation of hot-dip galvanized workpieces in vertical zinc furnace. In the process of entering and exiting the furnace of the hoister, the speed is required to be slow and uniform. First, to prevent the zinc liquid from splashing out of the zinc immersion furnace when the workpiece enters the furnace, and second, to prevent the output and export volume of the workpiece from increasing day by day, too much zinc is hung in the furnace, which affects the zinc immersion quality of the workpiece and wastes the zinc liquid. The overall production process requires that the minimum speed is 1m/min, and the motor can be adjusted in both positive and negative directions. It also requires that the two hoists can operate synchronously when the main motor source of the experimental machine is not on, so that the two hoists can operate synchronously when the workpiece is too long. In order to meet the process requirements, we use frequency converter to control the motor, and use edt00110m and edt0150fp to control two hoists respectively, which we call car a and car B. The control schematic diagram is as follows:

in the figure: Q0 is the main air switch of the system, Q1 and Q2 are the air switches for the frequency converters of a hoist and B hoist respectively, F1 and F2 are the frequency display tables, which are used to display the operating frequency of the motor. S9 and S10 are the rising limit switches of a and B hoists respectively. K1, zd1, K2 and ZD2 form two braking components, which are matched with two frequency converters respectively to consume the energy feedback when the hoist falls and prevent the over-voltage tripping of the frequency converter. F1, F2, SA1, SA2, SA3, SA4, W1 and W2 are all set on the manual operation box. In addition, the operation box also has the following control buttons: Crane forward and backward, a hoist left and right, B hoist left and right, trolley linkage and emergency stop buttons. For this transformation, we only transformed its lifting equipment. SA1 and SA2 are used for the rising and falling of a hoist, SA3 and SA4 are used for the rising and falling of B hoist, and the frequency conversion and speed regulation section switches of W1 and W2 hoists have three layers. Each layer has eight gears, and terminals 1, 2 and 3 are the common terminals of each layer. Their internal wiring is shown in the following figure:

four wires are led out from W1, of which G1, G2 and G3 are terminated with di1, di2 and di3 of the frequency converter, G4 is terminated with com, which is equivalent to connecting three switches on the di1, di2 and di3 terminals of the frequency converter. Eight different speeds are formed by using the multi-stage speed function of ed2003. By rotating the gear shift of the segment switch, the operating frequency of the motor can be flexibly changed, that is, the falling speed can be increased. There are 7 speeds in the frequency converter, which are respectively corresponding to 2 ~ 8 positions of the section switch. The 1 and 9 positions are stop positions, the 2-position frequency is 5Hz, the 3-position frequency is 8Hz, and the 4-position plastic packaging material made of chemical polymer alone is difficult to degrade in the natural environment. The frequency is 10Hz, the 5-position frequency is 12Hz, the 6-position frequency is 20Hz, the 7-position frequency is 30Hz, and the 8-Position frequency is 50Hz. We found and corrected the following problems during the commissioning process:

first, frequency setting

the initial frequency setting was given by the potentiometer externally, and the operating frequency was monitored by the frequency meter. During the commissioning, we found that this setting method could not accurately locate the set frequency, especially could not ensure the synchronous operation of the two hoists. Therefore, we used the above-mentioned internal setting of multi-stage frequency. After adopting this method, we can control the operating frequency of the motor very accurately, which can fully ensure the coordinated operation of the two hoists, and meet the requirements that the process essentials will find the linear change trend of the measured output signal of the amplifier unit

II. Abnormal mechanical transmission of motor

repeated experiments during commissioning found the following problems:

abnormal motor sound when B hoist is running, and under no-load condition, the current of B hoist is 3A greater than that of a hoist

a hoist uses the frequency converter to drive a hoist with the same parameters to operate normally. When driving B hoist, it fails to start or starts overcurrent under the same load

under the same load and working frequency, the motor current of hoist B is more than 7a larger than that of a, and the related parameter setting value is also larger than that of A. According to the above situation, we confirm that there is a problem with the motor or its mechanical transmission part of B hoist, and the problem is solved after replacing the motor. After the above commissioning process, the working current of the motor with a load of 2D tons is 10a, and the hoist can also work normally at a minimum of 5Hz

the following is the setting of ed2003 parameters:

the reformed hoist fully meets the requirements of the production process, and has been put into use with good results

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