kVA To Amps Single Phase Converter
Convert single-phase kVA to current in amps using voltage, with real-power, load margin and electrical safety notes kept separate from the arithmetic.
Convert Single-Phase kVA To Amps
Single-Phase Current Result
21.74 A
5 kVA at 230 V single phase is 21.74 amps.
This converter is for arithmetic and planning. Electrical installation work must be checked by a competent person.
Formula For Single-Phase kVA To Amps
VA = kVA x 1,000amps = VA / voltsamps = kVA x 1,000 / voltskW = kVA x power factorFor a single-phase apparent-power rating, current is kVA multiplied by 1,000 and divided by voltage. Power factor is not needed for that current conversion because kVA already includes apparent power. Power factor becomes relevant when you want an approximate kW value for real power.
Do not use a single-phase formula for a three-phase supply. Three-phase current uses the square-root-of-three relationship and line-to-line voltage. If a generator or transformer plate is unclear, read the full nameplate or ask a qualified electrician before using the result.
Common 230 V Single-Phase Values
| kVA | Amps At 230 V | Approx kW At PF 0.8 | Planning Note |
|---|---|---|---|
| 1 | 4.35 A | 0.8 kW | Small UPS, controls or light equipment. |
| 3 | 13.04 A | 2.4 kW | Near a common plug-load discussion, but plug rating is not the only limit. |
| 5 | 21.74 A | 4.0 kW | Small generator or workshop load planning. |
| 10 | 43.48 A | 8.0 kW | Larger single-phase supply or generator output. |
| 15 | 65.22 A | 12.0 kW | Needs careful cable, protection and installation review. |
Electrical Checks Before Using The Number
Nameplate Ratings
Check whether the equipment plate shows kVA, kW, volts, amps, duty cycle and phase. A motor starting current can be much higher than running current.
Cables And Protection
Cable size, installation method, grouping, temperature, voltage drop and protective device type all matter. This page does not size a cable or select a breaker.
Generators And UPS Units
A generator may have separate continuous and surge ratings. A UPS may have runtime limits as well as kVA limits. Compare the load profile with the equipment manual.
Worked Examples
A 3 kVA single-phase load at 230 V draws 13.04 A. With a 25% display margin, the planning current is 16.30 A. That margin does not automatically mean a 16 A circuit is suitable, because load type, duration, cable route and protection must be checked.
A 10 kVA single-phase generator at 230 V can supply 43.48 A by the apparent-power calculation. At a power factor of 0.8, the equivalent real power display is 8 kW. If a load has high starting current, the generator may still struggle even when the running kVA looks acceptable.
Planning Boundaries For Single-Phase Loads
The result is useful for first-pass checks, but it should not be treated as permission to connect equipment. A circuit has more limits than steady current. The protective device must suit the cable and fault conditions. The cable must suit the installation method, length, grouping, insulation, ambient temperature and voltage drop. The equipment may also have starting current, leakage current, duty-cycle limits or manufacturer instructions.
For generators and UPS units, compare both kVA and kW. A load with poor power factor can use a large share of the kVA capacity while delivering less kW. Motor loads, compressors and pumps may also need a short surge that is much larger than the running current. If the supply trips or the generator voltage sags at start-up, the running-current calculation was not enough.
For site notes, write the voltage used in the calculation. A current calculated at 230 V will differ from one calculated at 240 V or 110 V. If the supply is three-phase, do not adapt this answer by guesswork. Use the correct three-phase formula and the right line voltage.
Where the load is continuous, heat can become a practical limit. A cable, plug, socket, extension lead or enclosure that is acceptable for a short test may not be suitable for long operation near its rating. Check duty cycle, ventilation and manufacturer instructions, and get competent help where the load is fixed, high value or safety-critical.
For hire equipment, confirm whether the rating is input, output, standby, prime or continuous. Generators and UPS units often advertise more than one rating, and the safest comparison uses the rating that matches the planned use. Keep the hire sheet with the calculation, and record any stated surge limit. Include the cable and connector rating in the note. Add ambient temperature where relevant.
FAQ
What is the formula for single-phase kVA to amps?
Amps equals kVA multiplied by 1,000, then divided by volts.
Do I need power factor to convert kVA to amps?
No. For kVA to amps, kVA already represents apparent power. Power factor is used if you also want to estimate kW.
Can I use this for three-phase?
No. Three-phase current uses a different formula. Use a three-phase converter with the correct line voltage.
Is 230 V always correct in the UK?
230 V is a common nominal calculation value. Equipment labels, site conditions and permitted voltage variation may differ.
Does this choose a breaker size?
No. Breaker and cable selection needs design checks for current, fault protection, installation method, voltage drop and regulations.
Why is kW lower than kVA when PF is below 1?
kW is real power. kVA is apparent power. At a power factor below 1, real power is lower than apparent power.
Sources
- Health and Safety Executive. (n.d.). Electrical safety at work. HSE. https://www.hse.gov.uk/electricity/
- Institution of Engineering and Technology. (n.d.). Wiring Regulations. IET. https://electrical.theiet.org/bs-7671/
- International Bureau of Weights and Measures. (2019). The International System of Units (SI), 9th edition. BIPM. https://www.bipm.org/en/publications/si-brochure