Electricity: Specification for the Approval of Type of 80mA and 100mA class Measuring Current Transformers

Consultation period starts on January 5, 2010 and ends on February 15, 2010.

This consultation initiative will be of primary interest to Electricity sub-metering stakeholders, electricity meter owners and electricity meter manufacturers.

Recently, Measurement Canada (MC) has consulted with the Multi Customer Metering System (MCMS) manufacturers to discuss problems related to the re-verification of MCMS. Historically, the milliamp current transformers (mA CT) used with MCMS have always been considered as integral to the system, and therefore each mA CT was characterized with a specific MCMS input. This makes the re-verification of such systems very difficult and expensive because the mA CT must be removed and taken to the meter shop with the MCMS during re-verification. With the recent improvements in CT manufacturing technologies, high accuracy class mA CTs (0.1%) are now available on the market. A consensus during the consultation with MCMS manufacturers was that it is now time to approve mA CTs as a stand alone devices to enable them to be interchangeable and interoperable with MCMS which would be type approved as mA MCMS.

In developing this new standard, Measurement Canada has worked with manufacturers of mA CT and manufacturers of MCMS to identify characteristics that could best meet the needs of the submetering industry and the metrological requirements of MC.

In October 2009 the collaboration between Canadian Industry and Measurement Canada on the mA secondary class CT was presented to the IEEE SC Instrument Transformers (IT) Committee. This submission was well received and the current draft specification was submitted for consideration as an IEEE standard. The submission has been accepted as a base draft for development work. The project was assigned standard designation IEEE Std C57.13.7, an extension of the main C57.13 standard for IT taking into account its non conventional characteristics.

Hereby, Measurement Canada is seeking comments from industry stakeholders on the proposed standard. Please send your written comments to the undersigned before February 15, 2010.

View the consultation document

Luc Tessier
Senior Program officer
Measurement Canada | Industry Canada
2665 rue King ouest
Room 606
Sherbrooke, QC J1L 2G5
Telephone: 819-564-5737
Fax: 819-564-5740
luc.tessier@ic.gc.ca