GBP 640,000 control system contract signed

An Industrial Technology Systems (ITS) product story

Edited by the Engineeringtalk editorial team Aug 9, 2007

National Grid is installing new facilities to enable the supply of natural gas from the Milford area of Wales to the National Transmission System.

Industrial Technology Systems (ITS) has won a contract worth over GBP 640,000 to implement a Siemens PCS 7 control system based on PCS 7 architecture for National Grid National Grid's Churchover site, which currently receives gas from the North only.

This gas is compressed and piped off the station for delivery to Wales and the South West via the National Transmission System.

National Grid is installing new facilities to enable the supply of natural gas from the Milford area of Wales to the National Transmission System.

Amec has won the overall contract to install the gas compressor unit, new gas metering and new multi-junction valves including upgrades to the fire and gas, station protection and station control systems to support the new bi directional flow of natural gas.

Amec has awarded Industrial Technology Systems (ITS), a Siemens solution provider, a GBP 640,000 contract to design, configure, implement and test the PLC and Scada hardware and software for the Siemens PCS 7 control system based on Siemens PCS 7 architecture.

The new control solution, designed by ITS' engineers, will be fully dual redundant and consist of the Fire and gas, station protection and station control systems.

The solution will consist of two Siemens PCS 7 servers, three Siemens dual-redundant PCS 7 controllers on a fault tolerant industrial Ethernet network, two operator stations, dual-redundant I/O and power supplies.

The fire and gas system will be required to monitor all air spaces where a fire or accumulation of a potentially flammable gas may occur, to detect any hazardous events, to alert personnel and initiate timely executive actions in order to minimise the consequences of an event.

Connected to a number of detectors, the fire and gas system will interface with the station protection system to initiate the automatic shutdown of the plant should a hazardous event occur.

The system will monitor and collect fire and gas activity data such as flame, gas, rate of rise of temperature, and smoke detectors and provide the facility to expand this data into a management information system for reporting purposes.

The new station protection system will shut down the gas compressors in the event of a hazardous situation being detected by the fire and gas system.

It will continue to operate independently regardless of failures of any individual compressors.

The purpose of the protection system is to place the plant into a safe condition when the potential exists for an event to escalate into a catastrophic incident.

The main hazard associated with gas compression facilities is loss of containment of the gas following an explosion.

The station protection system will act as a defence against such an occurrence by disposing of the gas inventory contained within the equipment via the control system.

The station control system will provide control and monitoring of the process gas flow between upstream and downstream stations, such that the operation of the whole station is controlled in a safe manner.

The station control system will also have executive control over the gas compressors and an interface with existing control systems, flow computers and a telemetry system.

The safety integrity level required for each function in the plant control, shut down and control systems will be assessed, designed and implemented in accordance with the IEC61508 and 61511 principles.

Malcolm Knott, Managing Director of ITS said, "We are delighted to have won this project and will be dedicated to delivering it successfully and strengthening our relationship with Amec".

"Our team is looking forward to further use of the technology, expanding our knowledge internally and applying our expertise in IEC 61508 to win more safety-related projects in the future".