Timer OMRON PLC application in two-speed lift station to protect
http://www.factoryautmation.comPLC is a Timer application lift protect OMRON specially Timer application lift protect OMRON designed for application in industrial environment of digital computing operations electronic systems, in its internal storage to perform logical operations, sequential control, timing, counting and arithmetic operations such as instruction, and through the digital or template type of input and output to control various types of machinery or production process.
PLC because of its tool has reliable work, simple programming and easy to use, design and debug cycle short, etc has been the widely application of the elevator industry. According to incomplete statistics, in tianjin in 4100 kinds of the elevator, elevator PLC control has 562 units, including ac double-speed elevator adopts Japan OMRON C series PLC in the majority. According to the site safety inspection have lift drag part adopts ac contactor, concatenated motor stator winding impedance method with the contactor switch to add, deceleration control, end station security protection by mechanical force change speed switch, limit switch and the limit switch, etc. Despite of this kind of design can meet the needs of the operation, but in the use of possible contactor contact adhesion, spring failure, contact position, electrical components misoperation, switch failures such as mechanical damage is still "header or squat down bottom" accidents will happen. To prevent such failure, in addition to improve the quality of construction quality and components, we can use PLC underused in the timer and relay, with the help of PLC fault diagnosis function, application implementation end station protection, make up for the shortage, so as to improve the safety and reliability of the elevator.
When the elevator on the directional lines, auxiliary contactor KF upward direction relay SFJ0015, express, express operation contactor KY0501, door lock relay MSJ, more or less both in uplink contactor SX0502 electric suction, brake is opened, the elevator up. When met on force change speed switch SQH0016 capsules, PLC internal latch relay KRRP1001 to suck, timer Tim10, Tim11 start timing, length of time of the timing of the visible end station layer spacing and a ladder speed setting. Force change on speed switch, the elevator running into local train run by express, under normal circumstances, the upward flat layer elevator should stop. If did not stop capsules and to continue upward, when Tim10 value reduced to zero, the normally closed off, local train contactor MY0503 and uplink contactor SX0502 losing electricity, the elevator stops running. On the arrogant cars run into force after the change speed switch SQH0016, due to some reason the elevator to the local train running, running and express contactor KY0501 failed to release, when Tim11 value reduced to zero, the normally closed off, express run contactor KY0501 and uplink contactor SX0502J are losing electricity, the elevator stops running. Therefore, whether local train running or express, as long as the forced change speed switch SQH signal, whether other end station protection switch action, with the aid of Tim10 and Tim11 can make elevator stops running, so that the end station protection more reliable.
When the elevator need downward, as long as there is the selected command, downward direction relay XFJ0014 closed to the normally open point, keep latching relays are reset, Tim10 and Tim11 are losing electricity, the normally closed closed ready for elevator normal line. Bottom protection protection principle and the upper stand similar to not repeat.
This method had no effect on the normal operation of elevator, the use of running in good condition. Instructions as a result of the various types of PLC system are exactly the same, different function, depending on the specific situation, but is roughly in the same meaning.