Heat meters will be upgraded from industry standards to national standards

Reading: On April 5, Lu Shijian, director of the Institute of Standardization of the China Urban Construction Research Institute, revealed that the heat meter national standards have been submitted for approval and submitted to the National Standardization Administration for approval. The revision of the heat meter industry product standard (CJ128-2007) means that the heat meter will be upgraded from an industry standard to a national standard and will be approved for release this year.

On April 5th, Lu Shijian, director of the Institute of Standardization of the China Urban Construction Research Institute, disclosed that the application for heat meter national standards has recently been completed and is ready for submission to the National Standardization Administration for approval.

“The revision of the heat meter industry product standard (CJ128-2007) means that the heat meter will be upgraded from an industry standard to a national standard and will be approved for release this year.” Lu Shijian said.

Upgraded to national standard Since 2009, Lu Shijian's China Urban Construction Research Institute and other units have begun to make a second revision to the heat meter standard. The reference standard is the European standard EN1314-2007, and the third edition will be formulated as a national standard. The reporter has inquired from the National Engineering Construction Standardization Information Network and the heat energy meter has been listed as a national standard for editing products.

Lu Shijian said in an interview with this reporter that upgrading the heat meter to a national standard is to attract attention from a perspective of energy conservation and cover a larger area.

Zhao Yongfang, general manager of Dalian Shida Technology Co., Ltd.'s Beijing office, believes that companies should adopt this standard, which indicates that the country has put forward higher quality requirements for the heat meter industry.

The two major changes, Lu Shijian, said that the revision has increased the terms and conditions in line with national conditions, and even some provisions are more stringent than the new version of EN1314, especially the two major problems of flow sensor durability test and communication protocol.

The heat meter is mainly composed of a flow sensor, a temperature sensor, and an integrator. The accuracy of the flow sensor is a key component for ensuring the quality of the heat meter. Practice shows that the main problem with the heat meter is that the flow sensor does not shut off.

The highlight of this standard revision is to increase the basic durability test of the flow sensor, from the original constant flow, 300 hours of testing, to variable flow, 2400 hours of testing, to ensure that the five-year life index. Unlike the European standard, the 2400 hour temperature is set at 95°C.

Another major change was the issue of unified communications protocols that had encountered numerous corporate disputes and increased the requirements for remotely transmitting meter readings and data communications for optoelectronic interfaces.

Lu Shijian explained that in view of the lack of an operational agreement in China, the Ministry of Housing and Urban-Rural Development proposed a unified communication protocol in the “Heat Meter” standard (CJ128-2007). “If the manufacturer’s agreement is not uniform, the heat company will face many difficulties in the future and it will cause great waste."

The testing organization is challenged. For the long-term reliability of the heat meter, a variable flow, 2400-hour test is proposed, which will be no small challenge for the testing organization.

Jin Zhijun, secretary general of the China Metering Association's Heat Meter Working Committee, said that the testing organizations will face challenges such as time uncertainty and cost increase, so currently only nine companies have been granted heat meter type evaluation authorization.

From the perspective of time, the enterprise application type evaluation (prototype test) must submit an application to the local quality supervision bureau, and then the inspection agency is responsible for technical data review, type evaluation, etc. until the production license is issued, generally requiring the testing agency to complete within 3 months. Type evaluation work. Among them, the variable flow, durability test of 2400 hours test is only a type of evaluation project, 2400 hours (100 days, 3 months, equivalent to 50% to 60% of the entire heating season) for the testing agency "more difficult."

2400 hours of experiment can shorten the time? Germany's metrology agencies and some companies are simplifying with analog methods, which have taken more than ten days to obtain experimental data, but it takes time to wait for European standards to be revised.

From the perspective of cost, most of the institutions for endurance testing cannot do it. Because there is no durability test bench, the cost of using standard equipment is high, and only one or two sets of detection devices of the testing organization still have daily identification work. In addition, the use of a wear-resistant test bench requires 20,000 yuan, and only 6 heat meters are installed.

"Only 2400 hours of electricity costs are very high, causing the problem of high operating costs in the latter part of the year," said Jin Zhijun.