Concrete pump electric system in accordance with the different control methods can be divided into the following two forms. The first is the early relay-controlled system, the most representative of which are Schwing and Putzmeiter trailing pumps in Germany; the second is a microprocessor-based program Control system, the majority of the system controlled by the PLC, such as Sany Heavy Industry and Zoomlion companies such as the production of tow pumps. In the drag pump electrical control system technology, at present some of the domestic manufacturers have more than foreign manufacturers of technology, are used with a microprocessor control system. Electric control system is the "nerve center" of the trailing pump, which is an important guarantee for the normal operation of the trailing pump. Due to the complexity of the system, the fault location is also relatively difficult. In order to minimize the loss of production, the rapid detection and positioning of the electrical system failure of the concrete drag pump must be realized. The general maintenance ideas are: to be familiar with the working principle of the towing pump and the electrical logic of various actions, in accordance with the correct fault detection process and the use of effective fault detection means for testing, combined with scientific logic analysis and judgment, continue to narrow the fault Range, eventually find the point of failure. Under the premise of not damaging the trailing pump, adopt reasonable solutions and contingency plans to maintain production and deal with them in time after the production is finished. In this combination of practical problems encountered in the work for everyone to provide some cases to share with you. 1 Nippon Nippon NCP7SH concrete pump auxiliary motor start does not switch fault handling 1.1 Symptoms and Failure Analysis Nippon Nippon NCP7SH concrete pump auxiliary motor starting circuit control schematic diagram shown in Figure 1 (Note: according to the original drawing). Y- â–³ switching principle is also very simple, when the start button PB-3, 88-2Y contactor pull, time relay T-2 start delay, when the delay time, 88-2Y contactor release, 88 -2 â–³ contactor suction and hold, a Y-â–³ conversion process is over. However, some people simply can not figure out the clue that such a simple system fails. One day in the middle of the night, a Niigata iron NCP7SH pump construction in the suburbs appeared auxiliary motor start does not switch fault, start to Y-state is normal, but when the delay time after any case does not switch, the electrician to see I do not know the circuit diagram of Japanese painting, I called to ask, I used the phone to guide him to check the fault, but because it can not understand the circuit diagram or not deal with the fault. After I went to the scene inspection found that when the 10 seconds after the start, 88-2Y contactor is not released, while the 12 line without electricity, 88-2 â–³ contactor coil is normal, indicating the time between 16 and 17 relay T- 2 delay closed does not release, to determine the delay on the relay T-2 closed-point adhesion, and other contacts and delay function is also normal. 1.2 Troubleshooting When the construction site was still waiting for the construction, in which situation, can not get a substitute time relay, had to substitute other devices, the site has no spin button, no button switch, and finally had agreed to the other equipment On the removal of a down switch, the circuit in the line 13,16 removed, the line leads to 17. Will reverse switch connected as shown in Figure 2, and then replace the part of the dashed line in Figure 1, the manual control inverted switch instead of time relay do Y- â–³ conversion. Solve the construction site emergency problems. 2 Sany HBT60C-1816 motor towed pump displacement is not controllable fault handling 2.1 Symptom A control with a proportional valve after the Sany HBT60C-1816 pump start the motor, regardless of remote control, near control and positive and negative pumps are Action, but the displacement can only rise to 50% or so, can only be adjusted downward, up to stop at this point does not move, in this displacement can barely work. 2.2 Failure Analysis and Inspection and Treatment The concrete drag pump is used with a more advanced PLC control system with soft-start, and charged proportional valve control. Pump displacement stepless speed regulation, by adjusting the control panel 2SA knob input to the PLC increase or decrease emission signal, PLC output signal through the transistor T1 control displacement proportional valve DT0, adjust the proportional valve opening, to achieve stepless Adjust the pumping speed, change the pumping capacity.
Machine Room Elevator,Elevator Machine,Lift With Machine Room,Roomless Elevator
Homefriend&FUJI Elevator Co.,Ltd , https://www.jfujilift.com