Paragraph 7 Multi-rate meters
Induction meters
All multi-rate induction meters shall be tested on one rate in accordance with paragraphs 5 and 6. In addition, a further test shall be carried out on each and every other rate at a low load using Method A, Method B or Method C tests and at a high load using Method A test.
The difference in errors measured on one rate shall not differ from the errors measured on any other rate, for the same load conditions, by more than 1%.
Every rate change mechanism shall be tested for correct operation with an applied voltage of 90% of the marked voltage of the meter.
Static meters
All multi-rate static meters shall be tested on one rate in accordance with paragraphs 5 and 6.
On multi-rate static meters, where the total units is the sum of all the rates, a further test shall be carried out on each and every other rate at a high load using Method A.
On multi-rate static meters, where the total units is recorded on one register, only this register is required to be tested in accordance with paragraphs 5 and 6.