ATEX Pressure Data Loggers help keep Latvians Warm
09 July 2008
Over 250 ATEX certified pressure data loggers supplied by Signatrol are playing a crucial role in ensuring effective natural gas distribution to almost half a million homes, offices and buildings throughout Latvia.
The SL963X logger units have been supplied to Joint Stock Company “Latvijas Gâze, the largest energy supply company in Latvia. Latvijas Gâze, (LG) deals in the import, transmission, storage and sales of natural gas, which accounts for over 30% of all energy used in Latvia. Pressure monitoring throughout the network is a vital part of LG’s ongoing maintenance of their gas distribution system to ensure optimum supply of gas for their consumers. Given the working environment, any pressure data loggers need to be suitable for use in certified hazardous areas and originally LG used mechanical devices with paper charts to monitor the pressure fluctuations out in the field.
These units however, had a number of drawbacks, typically requiring time consuming and expensive ongoing maintenance. To keep them operational, it was necessary to send maintenance engineers to wind up the loggers’ clocks every seven days and change charts and ink as necessary. In addition, given the loggers’ very compressed time scale, it was difficult to identify pressure changes on the charts. Taking these factors into consideration, together with increasing prices for the mechanical loggers and ancillary components, LG took the decision to upgrade to electronic devices.
Signatrol’s ATEX certified SL963X data loggers were chosen based on their ruggedness and superior technical specification, including memory capacity, battery life and ease of data download. Featuring a fully welded 316 stainless steel pressure element, the data loggers are available in both gauge and absolute versions with pressure ranges up to 0-1000 bar.
The proprietary design of the piezoresistive measuring element provides exceptional long term stability and the high over-pressure capability prevents problems caused by pressure spikes. The self contained data-logger is fully sealed in aluminium housing together with its own battery, which unlike competitive units is user-replaceable, eliminating the need to return the unit to the supplier. Measurement intervals can be set from 2 seconds to 24 hours and this means that with a memory capacity of 130,000 readings and a maximum ten year battery life, the units can be used for very long term monitoring.
The SL963 units are installed on the downstream side of the pressure regulators in gas regulating stations to monitor the regulator performance and also at distribution system points where pressure fluctuation problems are known to exist. Pressure data is downloaded onto a computer on a regular basis using the RS232 interface cable. After evaluation of this information, any corrective technical measures are taken to improve the operation of the distribution system.
LG’s Technical Engineer Andris Polmanis is very pleased with the Signatrol units and as he concludes: “Pressure monitoring is an essential part of our maintenance program and we need to ensure data is recorded accurately and reliably throughout the year. The Signatrol units are very robust and have proved themselves to be more than capable of operating in our severe winter conditions. They offer significant advantages over our original mechanical units, allowing easy download and storage of pressure data.”
