Hants SP11 7AR
Two Systems Unlimited Posibilities
Veolia Waste Transfer Station using a fast response LISTEC addressable heat sensor cable which can monitor temperatures between -40°C and +85°C with a resolution of 0.1° and at the same time provide pin point accuracy from each measuring point within the cable.
“It‘s flexible, robust, maintenance free and easy to install which is highly suited to these type of environments”
The waste transfer site at Andover initially had an existing air sampling system installed, which proved to be problematic causing false alarms due to the environment and the nature of the day to day running operations.
Cables Britain Ltd are unaware of the in depth factual details that caused the building to have considerable fire damage, however we do know that it had severe consequences which led to commercial implications and disruption to the site operating conditions.
What was needed was a fast response fire detection system which could accurately identify the location where heat abnormalities were emanating, it needed to be stable, reliable and provide all the benefits of a programmable addressable fire system with false alarms being reduced to a minimum.
To be beneficial to the client it also needed to identify the temperature inside the building together with its waste contents as well as being able to set the alarm temperatures to suit the site conditions.
It was at this time when Cables Britain Ltd was first introduced to Core Investments and Veolia, where we demonstrated a product called LISTEC. A fast response addressable linear heat sensor cable which could be installed in dusty, dirty and aggressive environments and could be easily linked into the existing system.
In January 2010, Cables Britain Ltd were summoned to propose a solution to the fire strategy problems at site and design a system which would not be affected by the normal day to day site operations and at the same be robust, operate effectively and be sensitive enough to differentiate between normal and abnormal site conditions, with open protocols to link into the existing site system.
At this time Cables Britain Ltd did not have any specification so the picture was a blank canvas.
The system which we proposed was the Cables Britain LISTEC system, which consists of digital temperature measuring points each of which operates as a grade
1 heat detector, encapsulated in a robust cable at
pre determined positions along its entire length, these measuring points once in service monitor the temperature at 10 second intervals and are maintenance free.
One of the main unique advantages of this type of system is that the measuring points operate between -40°C to +85°C with a resolution of 0.1° and they can be individually programmed to operate at specific alarm temperatures giving pre alarm, fire alarm and fault outputs.
The sensor cable can operate as fixed temperature and fast response rate of rise in compliance with EN54 part 5. Both the rate of rise and fixed temperature elements of the system are adjustable and programmable outputs available making it ideally suited for this type of environment.
Should you wish to view our 10 minute LISTEC video in our Client Area. Please request a user name and password if you don’t already have one.
03 Trial Testing
In August 2010 we carried out various LISTEC trial tests, the client wanted to know what the temperature was at various levels within the transfer station and also what the temperature was within the waste itself.
It was agreed by all parties that we take temperature measurements at 4m and 8m levels within the transfer station. This was achieved by rolling a 20’ container full of waste materials into the station which had been fermenting under cover for approx 10 days. Tests were made 4m & 8m above the container and sensors were embedded within the waste to a depth of 1m with the station roller shutter doors open and closed respectively.
As soon as the LISTEC system was made active the average temperature above the container in each case was evident i.e. with the doors open; 23.3°C ,with the doors closed; 25.2°C and the waste was reading 34.4°C creating a differential (rate of rise) alarm within 40 seconds.
A mechanical heat source was then introduced with the roller shutter doors closed at minimum heat setting and within 40 seconds a differential (Fast response rate of rise heat temperature alarm) was given at both 4m & 8m levels respectively.
￼￼Also available for viewing is our full trial test report Ref: NB/MSIG/Veolia 001/Rev 0 dated 2nd August 2010 which can be sent upon request.
￼￼￼￼￼During the trial test various differential alarms settings were used. It was proved that for condensed monitoring the use of the SEC15/01 (Sensor cable with 1m sensor spacing ) be used and that the loading area form part of the protected area. This unique product can not only tell the engineer the specific temperatures anywhere in the transfer station but pin point to a measuring point in the cable whilst also providing the building’s average temperature.
It was noted that although the sensor cable was mounted at the 4m and 8m levels there was no significant difference between the temperature response time at both levels.
This proved to be a valuable tool as after the installation was carried out the the engineer could look for any trends i.e. changes in the seasonal temperature/inputs of different waste materials and adjust the alarm temperature threshold settings accordingly to suit the building conditions.
03a Trial Testing Installation
- The tests were completed at the 4m level and then repeated at 8m level.
- It was found that when LISTEC sensor cable was installed at both the 4m and 8m levels, there was no discernible difference in the response between the two levels when a heat source was introduced.
- The temperature data was recorded and logged onto a pc for future reference to enable the client to use within his fire strategy.
04 System Soak Testing
During the system soak testing period LISTEC had been subjected to a number of abnormalities for example, in July 2011 the system was producing pre alarms over the waste materials and on one occasion a fire alarm was generated.
This was easy identified, as when the system was originally installed and put into service during November 2010 the max. Alarm temperature level was set at 50°C and the differential fast response alarm level was set at 2.8°C as agreed with all parties concerned.
The system pre alarm temperature levels were set as:
- Absolute temperature pre alarm setting was set at 90% of the fixed temperature of 50°C
- Differential temperature pre alarm setting was set at 50% of the differential alarm of 2.8°C
04a The Solution
The fixed temperature pre alarms were produced due to the fact that the temperatures within the station had reach 90% of the actual fixed temperature alarm setting and on one occasion the temperature exceeded 50°C.
After consultation with all parties the maximum alarm temperature setting was increased to 60°C and the differential fast response alarm was left at 2.8°C which cured the problem.
LISTEC addressable linear heat sensing cable has been active at the Andover site for over 12 months and we can confirm that the system has been absolutely stable in all aspects and all the information collated is fully logged which can be down loaded to a pc for maintenance and service records.
All areas covered by LISTEC have pinpoint temperature accuracy, allows temperature variants for the seasonal weather conditions and enables the client to look for any temperature trends within the building making LISTEC ideally suited to dusty, dirty, humid working environments of this kind.
Case Study carried out on behalf of Core Investments Ltd for Veolia Waste Transfer Site at Andover using LISTEC Addressable Heat Sensor Cable.