EM – The incident happened on the afternoon of May 15th, when P.H apartment building (Vo Thi Sau street, Nha Trang city) used electrical generators to power the lighting systems and elevators. However, the generator suddenly caught on fire, causing the the elevator system to stop working, which consequently causedmany people to get trapped in the elevator.
On the morning of June 1st, the Management Board of P.H Apartment – P.H Nha Trang Investment Trading Joint Stock Company sent a letter of apology to residents about the generator fire incident in this apartment building and sincerely apologized for their failure to gain control over the situation as it arises, alongside their bad performance in ensuring that the elevator equipment is well maintained, which ultimately led to this incident.
Specifically, around 5 pm on May 15th, the substation of Le Hong Phong – Phuong Long Street (Nha Trang City) encountered a problem, therefore, the local electricity industry decided to cut off electricity supply on a large scale for reparation to take place. Immediately after the power went off, the P.H. apartment building operated the backup power generator to supply electricity to the elevator and light system in the apartment corridor.
However, after 15 minutes of operation, the backup power generator started to fail, emitting black smoke, thus causing the elevator system to come to a halt, many people inside the elevator were stuck. Numerous residents were concerned about a possible explosion in the apartment building, so they fled, creating a chaotic scene.
At 19:45 pm on the same day, the Investor and the Management Board of the P.H. apartment complex invited a technician to check and run another generator to supply electricity for the elevator and lighting system.
Image of black smoke rising from the P.H apartment building due to the electrical generator failure and the chaotic scene of residents fleeing (Photo: cut from video)
Today, the investor and the apartment management board have invited technicians to carry out an overall check on the backup generator to determine the exact cause of the problem and propose a timely maintenance plan.
In this situation, there are two core causes that need to be focused on.
To summarize the entire incident: when the power was cut off, the apartment building used a generator to allow the elevator system to carry on operating, then the generator caught on fire, causing the elevator to stop working, consequently, many people became trapped inside the lift.
After analysis, the first reason for this incident was that the elevator’s automatic rescue device was not working.
Usually, elevators are equipped with an ARD (Automatic Rescue Device) that provides backup power for the elevator system in case of a power failure using the stored energy for the battery. When there is a sudden power failure, this ARD automatically brings the elevator to the nearest floor and opens the door for people to exit. The total time from when the power goes out to the nearest floor door opening is approximately one minute given that the ARD operates on a backup battery source.
However, when the generator exploded and the power supply to the elevator was cut off, this ARD system did not work. Therefore, it is critical that this ARD system be re-examined.
Secondly, the use of an electrical generator as a backup power source to operate the elevator requires primary attention. It is essential to choose an electrical generator with an appropriate capacity (usually greater than 20-25% of that of the electrical equipment), and a stable output voltage, etc. Last but not least, regular maintenance and inspection are also required which helps the lift to be ready to operate without an error. The use of generators of poor quality, and unstable voltage causes electronic equipment (elevator boards, controls, computers, …) to easily lag or malfunction.
As an alternative to using electrical generators as a backup power source to operate the elevator, elevator manufacturers should research solutions to integrate backup power for elevators such as using batteries, storage batteries for electricity storage, etc.
