A Case Study Modernization yields good results for
Eastern Mumbai Residential Complexes
The elevators at the Gokul Gagan Chs. Ltd. residential tower in Kandiwali, East Mumbai, had become constant causes of complaints from those living in the 21-story building. Your author, as an elevator consultant, became involved in a project to modernize the approximately 20-year-old units.
The objective of this project was to both improve the performance and enhance the overall life of the elevators at the minimum possible expense, thus enabling users to enjoy the services of these elevators for years to come.
The building has four Otis units, two in each wing, installed in 1995-1996. Each unit has an eight-passenger capacity, automatic doors, 1-mps travel speed, collective down duplex and a servo drive system. They all serve ground to 21st floors. The units had undergone no major work or upgrades since they were installed, and the only large expenses incurred were for rope and pulley replacement, which were part of the service contract. These elevators were giving frequent problems. The number of calls were such that there was a complaint practically every other day. The users were frustrated, and the building society had begun considering the replacement of the original units.
The building society decided to hire a consultant to guide them as they sought the best solution, both in terms of durability and economical operation. This is where your author came into the picture.
Approach I circulated my article on the subject of upgrading an elevator, “How to Control Unexpected Major Elevator Repair/ Replacement Expenses” (ELEVATOR WORLD India, 1st Quarter 2013). The article provided the society a clear understanding of elevator systems, the lifecycle of the equipment and the necessity of replacing certain parts.The society committee members were very open minded, and most of them had a technical background, which made the job easier. A plan of action, which involved inspecting the elevators, studying the breakdowns and complaints, and working out the best solution that would satisfy the technical needs in an economical, long-lasting way without compromising safety, was formulated.
Along with the service provider, we carried out a detailed inspection of the equipment and its functioning. The major equipment, including the gear motors, brake systems, doors, wire ropes, safety gears and cabin frame assemblies, were determined to be in good condition and able to perform well for another eight to 10 years with regular service and adjustments. The controller was an old relay logic controller with carbon contact relays. The relays were beyond their lifecycle and no longer reliable. Uneven carbon contacts and contact tensions prevented the relays from functioning properly, which contributed to the frequent breakdowns. The relays were obsolete, and replacement with new ones was not possible. The other equipment in the machine room was in good condition and not a factor in the breakdowns. The shaft signaling system was also an old one. The electromechanical system used was obsolete and contributed to the breakdowns. The door locks and door operator were very old, also adding to the frequent breakdowns. The cabin frame and safety system were good and not in need of replacement. The cabin and platform flooring wereold and shabby, so we decided to go for a completely new stainless- steel cabin and double plate form to incorporate the latest requirement of an overload sensor. The car buttons and landing buttons were also obsolete, leading to breakdowns for lack of spares.
Study of the Breakdowns
Our study of the breakdowns and complaint records confirmed that the majority of the problems came from the controller, call buttons, door locks and shaft signaling system.
Our detailed study showed that the main reason these components were failing was technological obsolescence and expiration of lifecycle. We opted to upgrade the controllers,wiring, locks, door operators, landing and car buttons, and indicator system with the latest technology, which also came with a guaranteed 10-year availability from the supplier.
Various suppliers were contacted for quotations, and after some discussion and negotiation, the job was awarded to Otis. Work started in March 2016 and was completed by November 2016.
After the upgrade work was completed, the performance of the elevators was checked and found to be very encouraging:
- The start/stop was smooth because of the variable-voltage,Door opening/closing was smooth and reliable because of new operators with VVVF drives and new door locks.
- New stainless-steel cabin with false ceiling, concealed lighting, fan, music/announcement system and new flooring provided a decent ambiance inside the elevator.
- In addition, the new, microprocessor-based controller and VVVF drive system have resulted in substantial energy savings
In addition to the energy savings, the number of breakdowns was reduced to just six in six months among all four elevators. Waiting time at the ground floor is around 40 s., which is very good for residential apartments. A survey of users conducted after the upgrades were complete revealed a high level of satisfaction with the elevators’ performance. The building society was happy that, at reasonable expense, it will have good service from the elevators for another eight to 10 years.
Variable Frequency (VVVF) Drive System.
Written by : Rajnikant Lad
Founder Elevator Auditor | www.elevatorauditor.com
Watch Mr Lad and business leaders around the world talking about Elevator Safety and market trends on his our YouTube Channel : YouTube.
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