Product category:
Smaller-Sized PLCs
News Release from: Mitsubishi Electric Automation Systems | Subject: FX0N PLC
Edited by the Engineeringtalk Editorial
Team on 01 September 2000
Smoke detection system controlled by
compact PLC
A Mitsubishi Electric FX0N PLC is at the heart of Keltron's KCL S90C addressable control system which works alongside the mandatory fire detection system at Whiteleys Shopping Centre in Bayswater
Millions of customers and visitors are lured to Whiteleys Shopping Centre in Bayswater every year by famous names such as Marks and Spencer, Gap and Vidal Sassoon, as well as by exhibitions, charity events, fashion shows and weekly concerts staged by Whiteleys The Grade II listed building, which was renovated in 1989, contains 77 shops, ten restaurants, an eight-screen multiplex cinema, a health club and a rooftop car park
High Wycombe based Keltron Controls has upgraded the smoke control system essential for safe evacuation of the shopping centre in the event of fire.
A Mitsubishi Electric FX0N programmable logic controller (PLC) is at the heart of Keltron's KCL S90C addressable control system which works alongside the mandatory fire detection system, sequentially switching motorised dampers and fans to provide optimal smoke clearance in 11 zones, each with four motorised smoke dampers.
Sixteen fans are used in either extract or supply modes to extract smoke from fire zones or supply make-up air to non-fire zones.
The PLC accesses via the KCL S90C communications interface as many as 100 field units which monitor or control the sensors, fire or smoke dampers and fans via a two-wire fieldbus network which is independent of the building management system.
A major benefit of the distributed design is reduced cabling costs in facilities such as shopping malls, offices, hotels, hospitals and factories.
This makes it particularly cost effective for retrofitting existing buildings.
The 'field units' can be up to 2km from the central controller, linked not only to fire and smoke dampers and fans, but also to lighting and motors, alarms and security points, where the cost of dedicated wiring is high.
The larger the building or site, the greater the saving.
Each field unit possesses a unique address to enable it to communicate with the central controller, and has inputs and outputs which are read or set by instruction from the controller.
A Mitsubishi FX0N PLC runs the application program with the KCL S90C interface simply acting as the link between the FX0N and the field units.
Many functions are available with the FX0N PLC, and the application software can be easily programmed or modified using Mitsubishi programming tools.
Steve Laughlin, sales manager at Keltron Controls, says "We are beginning to look at large installations where many PLCs will be used on a network.
The days of smoke control systems requiring bespoke hardware and software are a thing of the past.
We are very happy with the Mitsubishi FX0N because it is extremely reliable and software programming is easy.
Anyone can understand the ladder logic which facilitates ongoing maintenance." The Whiteleys installation designed by Keltron has two FX0N and KCL S90C controllers - one duty and one standby.
The status of the duty system is monitored by a 'watchdog' device and changed over to the standby system as soon as a fault is detected within the duty controller.
Communication with the field units is bidirectional, preserving the integrity of the system by creating tolerance of breaks and short circuits which, if they occur, are handled by line isolators installed in the communication loops. Request a free brochure from Mitsubishi Electric Automation Systems ...
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