Summary of judgment method of elevator fault

Summary of judgment method of elevator fault

If we want to quickly and accurately determine the elevator fault, firstly we need to understand the basic structure of the elevator equipment ,understand the working principle of the components, and also familiar with working principle and the operation principle of elevator system.

First,we need to know the basic operation principle of traction elevator.

All we know, elevator need the power supply to run.The basic power is 3 phase 380V AC power supply and single phase voltage 220V,Plus or minus 7%.

One of the necessary conditions for the elevator operation

When the safety circuit is switched on, the safety circuit is disconnected, and the elevator safety signal is cut off, and the elevator can not be operated.

Elevator safety circuit includes:

1.Inside the machine room：

Safety circuit breaker;speed governor;machine room emergency stop.

2.Car top：

Safety gear,Door machine switch;car top inspection box,Safety window switch

3.Pit：

Car buffer switch(S1),counterweight buffer switch(S2),Tension device switch,pit inspection box.

4.Shaft：

Upper limit (upper end station), lower limit (lower end station).

Safety circuit voltage is generally AC110V, and some elevators are not the same, can be identified in the electrical schematic.

The second necessary conditions for the elevator operation

Door lock loop:

1.Door lock parts

Hall door lock hook depth 7mm; when electrical interlock is normal working,under the condition of the door hook not started, the doors lift should not stop.

2.Car door lock

After the door is closed, the door lock should be guided.

3.Door closing switch

After the door is closed, the door closing switch should be closed, and the door should not be operated when the door is closed.  

Elevator door lock loop can not be shorted, otherwise it may cut accidents in our elevator maintenance is completed, such as short seal line, must put the seal plug after short can restore the elevator. Recovery test method for elevator has to check again the door lock circuit is normal, disconnect the lock loop,if the elevator does not move, which is normal.

The third necessary conditions for the elevator operation

Brake circuit and drive circuit

Brake circuit ：

The traction machine operation, we mentioned safety loop and lock loop in the above.When meet these two conditions above, the brake to begin work, when the door lock and the safety circuit of relay, as long as the board receives the start signal, immediately issued at the same time, start the brake and traction machine orders, then the main contactor (contactor control the motor power supply) and brake contactor should also pull the power supply to the brake and traction machine.

The fourth necessary conditions for the elevator operation

Flat layer and position system:

Flat layer sensor,Door area switch,upper/lower forced change,limited switch.

Flat layer sensor and door area switch is installed in the elevator car top.

Upper/lower forced change and limited switch are installed in the top and bottom of elevator shaft.

The fifth necessary conditions for the elevator operation

Communication system: Is basic in elevator design

The elevator car display, button and call display, then back to the main board. 

1.Communication cable must be used twisted pair shielded wire(with plastic and copper wire)

2.The signal of the car communication board must be connected with the main board at all times.

3.Communication lines should be far away from the 220V power to prevent interference.

In case of communication failure, we can start from the car to check, the first observation car board communication signal is normal (indicator general Chang Shan), if not normal can pull off one by one button or the display board to exclude, so is the call.Should also check commercial elevator 

installation position and the communication line is damaged, check communication voltage.

The reason why the elevator can't be closed   

1. Elevator into protection state

2.The light curtain or safety board fault

3.Door opening button or call button stuck

4.Mechanical clamping

5.Main-board can not output closing signal

6.Over loading

7.Switch door in place is not normal

8.Door operator faulty

   

When we buy escalator and elevators,we need to have a preliminary understanding of the above.And all professional elevator companies must know all these technologies.