Paragraph 4.2 Effect of disturbances of long durationF1
Table 3
| Critical change values for disturbances of long duration | |||
|---|---|---|---|
| Disturbance | Critical change values in percent for meters of class | ||
| A | B | C | |
| Reversed phase sequence | 1.5 | 1.5 | 0.3 |
| Voltage unbalance (only applicable to polyphase meters) | 4 | 2 | 1 |
| Harmonic contents in the current circuits | 1 | 0.8 | 0.5 |
| DC and harmonics in the current circuit | 6 | 3 | 1.5 |
| Fast transient bursts | 6 | 4 | 2 |
| Magnetic fields; HF (radiated RF) electromagnetic field; Conducted disturbances introduced by radio-frequency fields; and Oscillatory waves immunity | 3 | 2 | 1 |
In the case of electromechanical electricity meters, no critical change values are defined for harmonic contents in the current circuits and for DC and harmonics in the current circuit.
Annotations
Textual amendments
- F1
Schs. 1A-1K inserted (E.W.S.) (31.12.2020) by The Product Safety and Metrology etc. (Amendment etc.) (EU Exit) Regulations 2019 (S.I. 2019/696), reg. 1, Sch. 27 para. 49 (with Sch. 27 para. 50(a)) (as amended by S.I. 2020/676, regs. 1(1), 2); 2020 c. 1, Sch. 5 para. 1(1)