小知识电梯电气维修常识（Small knowledge elevator electrical maintenance common sense）Small knowledge: elevator electrical maintenance common senseElevator portal, December 28thSafety circuitEffect：To ensure the safe operation of the elevator, many safety components are installed on the elevator. The lift can run only when each safety component is in normal condition, or the elevator will stop running immediately.The so-called safety loop, that is, in the elevator, each safety component is equipped with a safety switch, put all the safety switches in series, control a safety relay. Only when all the safety switches are connected, the safety relay is attracted and the elevator can be operated electrically.L common safety circuit switch:Engine room: control panel, emergency stop switch, phase sequence relay, thermal relay, speed limiter switchHoistway: upper limit switch, lower limit switch (some elevators place the two switches in the safety circuit, and others use these two switches to control the power supply directly)Pit: broken rope protection switch, emergency stop switch, maintenance pit box buffer switchCar: control box, emergency stop switchCar top: safety window switch, safety tongs switch, car top overhaul box, emergency stop switchFault state:When the elevator is stopped, all signals can not be registered, train traffic are not running, the first suspect is the safety circuit fault. You should observe the status of the safety relay in the control panel of the engine room. If the safety relay is in the release state, it shall be judged as a safety loop fault.Possible cause of failure:The phase sequence relay action of the 1. input power supply is caused by phase sequence errors or missing phases.2., the elevator for a long time in excess load operation or blocking, causing thermal relay action.3. speed limiter may cause overspeed switch action at overspeed.4. lift the lift or sink caused by limit switch.5. pit rope breaking switch. Maybe the speed limiter rope jumps out or over length.6. safety tongs action. Reasons should be found out. May be the overspeed limiter action, oil leakage misoperation, oil leakage, pit pit rope pulley rope wheel of a foreign body (such as mice), involved in the security clearance is too small a wedge.7. safety windows are raised, causing safety window switch action.8. some emergency stop switches are pushed down.9., if the switch is normal, should check whether the contact is good, the wiring is loose, etc.In addition, although now more elevator safety loop normal safety relay is also attracted, but usually in the safety relay takes a normally open contact and then sent to the micro payment (or a PC) were detected, if the bad safety relay itself, the state will cause the safety circuit fault.Lock circuitEffect：To ensure that the elevator must be closed after all doors to run, in each hall door and car doors are equipped with electrical interlocking door switch. Only when all the door electrical interlocking switches are fully connected, the door lock and relay of the control panel can be pulled in and the elevator can run.Fault state:When all the doors are closed, observe the status of the door lock relay on the control panel. If the door lock relay is in the release state, the door lock circuit should be judged to be disconnected.Maintenance method:Because most of the current lift off slow fast in the locks are not running, so although it is easy to lock fault judgment, it is difficult to find out which is the door fault.My maintenance suggestion:1., first of all, should focus on suspected elevator stop layer door lock is faulty.2. ask if there is a triangle key to open the cross door, and use the triangle key in the hall to switch the hall door again.3. to ensure that in the maintenance status, in the control screen separately from the short hall, door locks and office locks, the office is divided into the door part or car door part of the fault.4., if the door part of the fault, to ensure that the state of repair, short hall lock circuit, to speed up the operation of elevators, check every floor door interlock contact (do not forget the passive door).Note: after repairing the fault of the door lock circuit,We must take off the door short wiring, can lift back to express state.In addition, although now more elevator door lock loop lock relay is also normal, but usually pull the lock on a relay normally open contact and pay to the microcomputer (or PC) were detected, if the contact locking relay itself, the state will also cause the lock circuit fault.Safety contact plate (door door, photoelectric screen)Effect：In order to prevent the elevator door shut in the closing process of passengers, so the general safety in the elevator car door is provided with a touch panel (or photo or screen).Safety: clamping proo