Voltage Transformer Accuracy Classes
Voltage Transformer Accuracy classes according to IEC 61689-3
Class | Range | Limits of errors | Application | ||
Burden % | Voltage % | Ratio % | Phase displacement Minutes | ||
0.1 | 25-100 *) | 80-120 | 0.1 | 5 | Laboratory |
0.2 | 25-100 *) | 80-120 | 0.2 | 10 | Precision and revenue metering |
0.5 | 25-100 *) | 80-120 | 0.5 | 20 | Standard revenue metering |
1.0 | 25-100 *) | 80-120 | 1.0 | 40 | Industrial grade meters |
3.0 | 25-100 *) | 80-120 | 3.0 | - | Instruments |
3P | 25-100 *) | 5-FV **) | 3.0 | 120 | Protection |
6P | 25-100 *) | 5-FV **) | 6.0 | 240 | Protection |
*) For burdens<10 VA, 0 - 100%, PF = 1
**) FV = Voltage factor
Voltage Transformer
Accuracy classes according to IEEE C57.13
Class | Range | Power error at metered load PF 0.6-1.0% | Application | |
Burden % | Voltage % | |||
0.15 | 0-100 | 90-110 | 0.15 | High-accuracy metering |
0.3 | 0-100 | 90-110 | 0.3 | Revenue metering |
0.6 | 0-100 | 90-110 | 0.6 | Standard metering |
1.2 | 0-100 | 90-110 | 1.2 | Relaying |
1.2R | 0-100 | 90 | 1.2 | |
25 | 3 | Relaying CCVT | ||
5 | 5 | |||
Standard burdens | VA | PF | |
M | 35 | 0.20 | |
W | 12.5 | 0.10 | |
X | 25 | 0.70 | |
Y | 75 | 0.85 | |
Z | 200 | 0.85 | |
ZZ | 400 | 0.85 |