Did the elevator get heatstroke? Do you know why you are trapped in the elevator on a hot day?

Elevator failures occur frequently in many communities across the country.

In Enshi, Hubei, an elevator broke down.

9 people were trapped 1 hour, and the elderly and children fainted;

In Pingxiang, Jiangxi, the elevator in a residential area broke down.

Causing 10 residents to be trapped.

Similar sleepy events often occur in Hangzhou.

A few days ago, an elevator maintenance worker in Hangzhou was doing maintenance work.

Stuck between the elevator car and the elevator shaft and died.

Later, after investigation and preliminary analysis by the quality supervision department,

It is suspected that it is caused by illegal operation of elevator workers.

According to the data analysis of Hangzhou 96333 Emergency Disposal Center,

Most people trapped in elevators occur in July and August, which is the dog days.

So, what is the relationship between temperature and elevator accidents?

Curious laboratory of Hangzhou quality supervision bureau,

With the cooperation of Hangzhou 96333 Emergency Disposal Center

Do an experiment.

There is a control cabinet in the computer room.

The normal operation of the elevator and all protective measures,

All instructions are issued through the frequency converter in the control cabinet.

And signals sent by the circuit motherboard.

There is also a drive host and a speed limiter in the computer room.

For the elevator, the computer room is like a headquarters.

It is the core to control the safe operation of elevators.

The elevator runs frequently,

The temperature of elevators and components will continue to rise.

The experimenter beat an egg on the brake resistor box.

In three minutes, it will be cooked.

So, what will happen when you take the elevator at this time?

The answer is trapped. ...

Wang Libin, engineer of Hangzhou 96333 Emergency Disposal Center, said,

When the ambient temperature is too high,

The temperature of the electronic components of the control cabinet will also increase,

When the temperature rises to a certain extent,

When its thermal protection switch is activated,

The elevator will stop to protect itself.

If that elevator is operate in a continuously high temperature state,

The circuit board and some electronic components of the elevator controller,

There may be some exceptions in the program.

This will cause, for example, the elevator to stop suddenly during normal operation,

Or when operating in a flat layer,

The phenomenon of not opening or closing the door.

Wang Gong said:

The control temperature of thermistor in the driving host is about 85℃

The temperature control switch of the control cabinet is about 65℃.

When the temperature of the electronic component exceeds these two temperature limits,

The elevator will be thermally protected and stop.

Therefore, national standards require that,

The air temperature in the elevator machine room is kept between 5~40℃

If the temperature exceeds 40℃, the temperature control device must be turned on to help dissipate heat.

Hangzhou 96333 emergency management center

A sample survey of more than 9,000 elevators found that,

Only about 1800 elevators are equipped with air conditioning.

Less than 20%?

In addition, the general computer room location is on the roof.

The space is small and stuffy,

The recent outdoor temperature in Hangzhou has reached 40℃.

It is difficult for the computer room to meet the requirement of 5-40℃ without air conditioning.

In addition to the elevator "heatstroke" fault,

The elevator suddenly lost its temper,

In fact, it is more about the passengers themselves.

For example, some people like to ride an electric car into the elevator.

What will happen if the electric car hits the elevator?

The elevator was running normally, and the electric car on the first floor hit the elevator.

The elevator door is slightly concave inward,

The elevator is stuck between the first floor and the second floor.

The uncivilized behavior of the passengers downstairs,

Actually caused the elevator upstairs to malfunction,

Why is this?

Zhang Hongbing, director of ofo Elevator Development Center, said,

The elevator doors on each floor actually have safety switches.

Once there is an abnormality, it will trigger the elevator to stop.

The elevator is sleepy

In fact, the control system detects an abnormal signal,

Triggering a protective device is like stopping a brake.

There are many similar situations in life.

For example, forcibly tearing open the door of the car,

If the circuit is broken, the elevator will be forced to stop.

Causing people to be trapped.

Another example is the renovation of the new community.

Decoration garbage frequently enters and exits the elevator and leaks into the door.

The elevator hall door is not closed properly. After opening and closing the door three times in succession,

The elevator will stop.