Every power cable carries a voltage rating written as two numbers, for example 450/750 V or 0.6/1 kV. This pair is called U0/U. Older standards and datasheets write the same thing as E0/E.
What the two numbers mean
- U0 is the voltage the cable is designed for between any conductor and earth (or the cable's metallic screen, where it has one).
- U is the voltage the cable is designed for between any two phase conductors.
Both are r.m.s. values at power frequency (50 or 60 Hz). In a balanced three-phase system, U is √3 times U0, so 230 V to earth gives 400 V between phases.
Ratings across the Goldberg range
| Cable | U0/U |
|---|---|
| H03VVH2-F | 300/300 V |
| H05VV-F | 300/500 V |
| H07RN-F | 450/750 V |
| H07V-K | 450/750 V |
| NSHTÖU-O/J | 0.6/1 kV |
How to use the rating
Choose a cable whose U0 is at least the supply's voltage to earth and whose U is at least the voltage between phases. Singapore's low-voltage supply is 230/400 V, so a cable rated 450/750 V or 0.6/1 kV covers it with margin to spare.
The rating is not the same as the test voltage on a datasheet, such as 2.5 kV or 3.5 kV. That is a higher voltage applied once in the factory to prove the insulation, not a voltage to run the cable at.
Not sure which rating your project needs? Ask our team and we'll recommend a cable.
