For an electrical core component of a printing press, rather than a one-time investment, to avoid the trouble caused by frequent failure in the future. Of course, if you have confidence in the other brand quality and performance indicators of the inverter, you can also choose to save some. After having the drive hardware, set its internal parameters. In terms of speed parameters, the jog frequency can be set to 2.5Hz, the initial printing speed is 25Hz, and the high speed is about 60Hz. The following uses the Mitsubishi A540 Series 400V and 11kW products as an example to describe its specific wiring and its connection with the old press. The two lines are shown in the attached drawings. The relevant precautions are as follows.
(1) The main drive of the original printing press is an electromagnetic speed control (slip) motor, a low-speed motor, clutches, brakes, etc. All are removed and replaced, and a special motor of frequency conversion speed control produced by Shanghai Tongtai Motor Co., Ltd. is used instead. Machine 11kW/380V comes with three-phase power brake and cooling fan. The mounting base of the original motor can be used, and the pulley of the original motor can also be removed and mounted on the new motor shaft.
(2) Since the original main motor and low-speed motor have been removed, the wiring of the main contacts of the contactors KM1, KM2, and KM3 in the distribution box can be removed. The rest of the available contacts are used in accordance with the new line as switching contacts for the drive control signals. Because the contacts of the original relay may have a longer use time and poor contact, it is better to replace it. Forward input terminal STF, reverse input terminal STR, medium speed terminal RM, low speed terminal RL, reset terminal MRS, common terminal SD wiring of the frequency inverter need to be combined in parallel with related contact strings to meet three-step speed regulation requirements.
(3) The original electromagnetic governor ZLK-11 was also removed, and it was possible to make a suitable speed gage display box using its mounting position, using a 1KΩ/ZW wire potentiometer to access the analog signal input port - 10E , 2.5, with a full-scale 10V DC voltmeter in parallel with the 2.5 side, change the indicator unit in the dial, you can indicate the command speed of the inverter.
(4) Inverter internal alarm normally closed contacts B, C connected to the serial circuit of the original control circuit KA1, so that after the action with the machine emergency stop function.
(5) Control the main motor contactor KMa and connect it to the original line KA1. If an alarm is released, the main motor circuit is disconnected and at the same time KA1 normally closed contact is closed, resetting the inverter and prohibiting output. Cooling fan, electromagnetic brake contactor KMb coil connection has two branches, one is in series KMa normally open contact with KMa in parallel, and the other is with the power supply in series into the car safety switch normally closed contact. Normally, the branch is disconnected. When a manual cranking is required, the power supply also energizes the KMb via the safety switch, and the brake is released to crank.
(6) There are two ways to install the inverter. The first is to make another control box, which is placed in the appropriate position on the bottom of the feeder plate. The other is that if the control cabinet is close to the wall or the column, the control box can be fixed on the wall or column, through the harness and the tube The original control cabinet is connected.
4 Conclusion
After the above steps, the author successfully reconstructed an old J2205 sheetfed two-color lithographic printing machine. After the transformation, the captain showed that the speed was stable, the speed was accurate, and the energy efficiency was high. The maintenance personnel also felt high reliability, and almost no extra maintenance was required. We actually measured the current consumed during the production of the printing press before and after the conversion, and made comparisons and calculations to conclude that at least 30% of energy was saved. As shown in the attached table: With 20 hours of production per day and 280 days per year, electricity consumption can be reduced to 16800kWh per year, at 0.7 yuan per kilowatt-hour electricity, and electricity savings can be saved by only 11,760 yuan per year. The electromagnetic clutch used for clutch and brake is easily damaged due to poor working environment. To replace 4 each year, each 250 yuan, and can save 1,000 yuan. We spent 7800 yuan for the inverter, 8,000 yuan for the inverter motor, plus a total of about 16,000 yuan for some wires and relays. Compared with investment and output, the entire investment can be recovered in less than a year and a half. Of course, this does not include the indirect benefits of improved productivity and improved print quality.
(1) The main drive of the original printing press is an electromagnetic speed control (slip) motor, a low-speed motor, clutches, brakes, etc. All are removed and replaced, and a special motor of frequency conversion speed control produced by Shanghai Tongtai Motor Co., Ltd. is used instead. Machine 11kW/380V comes with three-phase power brake and cooling fan. The mounting base of the original motor can be used, and the pulley of the original motor can also be removed and mounted on the new motor shaft.
(2) Since the original main motor and low-speed motor have been removed, the wiring of the main contacts of the contactors KM1, KM2, and KM3 in the distribution box can be removed. The rest of the available contacts are used in accordance with the new line as switching contacts for the drive control signals. Because the contacts of the original relay may have a longer use time and poor contact, it is better to replace it. Forward input terminal STF, reverse input terminal STR, medium speed terminal RM, low speed terminal RL, reset terminal MRS, common terminal SD wiring of the frequency inverter need to be combined in parallel with related contact strings to meet three-step speed regulation requirements.
(3) The original electromagnetic governor ZLK-11 was also removed, and it was possible to make a suitable speed gage display box using its mounting position, using a 1KΩ/ZW wire potentiometer to access the analog signal input port - 10E , 2.5, with a full-scale 10V DC voltmeter in parallel with the 2.5 side, change the indicator unit in the dial, you can indicate the command speed of the inverter.
(4) Inverter internal alarm normally closed contacts B, C connected to the serial circuit of the original control circuit KA1, so that after the action with the machine emergency stop function.
(5) Control the main motor contactor KMa and connect it to the original line KA1. If an alarm is released, the main motor circuit is disconnected and at the same time KA1 normally closed contact is closed, resetting the inverter and prohibiting output. Cooling fan, electromagnetic brake contactor KMb coil connection has two branches, one is in series KMa normally open contact with KMa in parallel, and the other is with the power supply in series into the car safety switch normally closed contact. Normally, the branch is disconnected. When a manual cranking is required, the power supply also energizes the KMb via the safety switch, and the brake is released to crank.
(6) There are two ways to install the inverter. The first is to make another control box, which is placed in the appropriate position on the bottom of the feeder plate. The other is that if the control cabinet is close to the wall or the column, the control box can be fixed on the wall or column, through the harness and the tube The original control cabinet is connected.
4 Conclusion
After the above steps, the author successfully reconstructed an old J2205 sheetfed two-color lithographic printing machine. After the transformation, the captain showed that the speed was stable, the speed was accurate, and the energy efficiency was high. The maintenance personnel also felt high reliability, and almost no extra maintenance was required. We actually measured the current consumed during the production of the printing press before and after the conversion, and made comparisons and calculations to conclude that at least 30% of energy was saved. As shown in the attached table: With 20 hours of production per day and 280 days per year, electricity consumption can be reduced to 16800kWh per year, at 0.7 yuan per kilowatt-hour electricity, and electricity savings can be saved by only 11,760 yuan per year. The electromagnetic clutch used for clutch and brake is easily damaged due to poor working environment. To replace 4 each year, each 250 yuan, and can save 1,000 yuan. We spent 7800 yuan for the inverter, 8,000 yuan for the inverter motor, plus a total of about 16,000 yuan for some wires and relays. Compared with investment and output, the entire investment can be recovered in less than a year and a half. Of course, this does not include the indirect benefits of improved productivity and improved print quality.
Dish Drainer Rack,Dish Rack,Dish Drying Rack,Kitchen Counter Cabinet
Qin Jian International Limited , https://www.luanbosmart.com