5, 10, and 30 kVA stabilizers: what each size can carry.
Compare 5, 10, and 30 kVA voltage stabilizers: real kW at 0.8 PF, typical loads, single-phase and three-phase options, and input range requirements.
- 5 kVA at 0.8 PF
- 4 kW
- 10 kVA at 0.8 PF
- 8 kW
- 30 kVA at 0.8 PF
- 24 kW
- Servo output
- ±2%
The 5, 10, and 30 kVA sizes cover most small and medium stabilizer applications. The difference is not just capacity: the 5 kVA unit is often single-phase and sits in a shop or a lab; the 30 kVA unit may be three-phase and sits at the incoming supply of a small factory or a commercial floor.
At a 0.8 power factor, a 5 kVA stabilizer delivers 4 kW, a 10 kVA delivers 8 kW, and a 30 kVA delivers 24 kW. Add 20–30% margin for growth and motor starting, and confirm the input window before choosing.
How do the three sizes compare?
5 vs 10 vs 30 kVA stabilizer
| Criterion | 5 kVA | 10 kVA | 30 kVA |
|---|---|---|---|
| Real power at 0.8 PF | 4 kW | 8 kW | 24 kW |
| Typical phase | Single-phase | Single-phase | Single or three-phase |
| Typical load | Shop, lab, small office | Home, clinic, office floor | Factory line, hotel, building |
| Input window (servo) | 160–260 VAC | 160–260 VAC | 160–260 / 304–456 VAC |
| Output accuracy | ±2% | ±2% | ±2% |
| Mounting | Floor cabinet | Floor cabinet | Floor cabinet |
What can each size actually run?
A 5 kVA stabilizer can run a small shop with a fridge, a freezer, lights, a POS, and a computer. A 10 kVA unit can run a clinic with a small air conditioner, a lab bench, and office equipment. A 30 kVA unit can run a production line, a hotel floor, or a water-treatment panel.
Do not run a motor load at the full stabilizer rating. A 3 kW motor with a direct-on-line start can draw 15–20 kW for a few seconds. Use a soft starter or oversize the stabilizer after a load study.
Which size should I choose?
Measure the load, not the nameplate. Add 20–30% margin. If the load is single-phase and below 8 kW, a 10 kVA unit is usually the practical choice. If the load is three-phase and above 16 kW, a 30 kVA three-phase unit with independent phase regulation is the better fit.
If the input voltage regularly falls below 160 V single-phase or 304 V three-phase, a servo stabilizer will not hold the output. Fix the upstream supply or choose a wide-input UPS.
Which standards and documents are referenced on this page?
The table lists the model-specific standards and conformity documents a project buyer should ask for. Availability depends on the frame, the battery, and the destination market; request the document that names your model.
Voltage stabilizer and AVR standards
| Reference | What it covers |
|---|---|
| IEC 61558-1 | Safety of power transformers and supply units |
| IEC 61000-3-2 | Harmonic current emission limits |
| IEC 61000-3-3 | Voltage fluctuation and flicker limits |
| IEC 62040-3 | Interface performance when feeding a UPS input |
| JB/T 10089 | Contact-type AC voltage stabilizer standard |
| GB/T 12325 | Voltage deviation limits for supply systems |
| CE / RoHS | EU conformity and restricted-substance declaration |
| ISO 9001 | Manufacturing quality management system |
| RS485 / MODBUS-RTU | Remote monitoring interface |
| IP20 / IP21 | Enclosure protection for indoor installation |
Certificates are issued against the exact model and configuration. See the certifications page for how to confirm scope and revision, or send the model to request the current document.
Confirm the inputs and documents before quoting.
Project inputs to confirm
| Item | What to confirm | Why it matters |
|---|---|---|
| Load | Running kW, largest motor, load step | Sets kVA, overload and topology |
| Runtime | Minutes, generator availability, battery room | Sets battery bank and charger |
| Supply | Voltage, frequency, phase, input current | Sets model, breaker and cable |
| Site | Country, altitude, ambient temperature, dust | Sets derating, IP and documents |
| Battery | VRLA, LiFePO4, footprint, weight limit | Sets chemistry and room layout |
| Documentation | Conformity route, test report, language | Sets document package and lead time |
Match the page to a platform.
SVC Series · 0.5–100 kVA
Servo Voltage Stabilizer
±2% output from a 160–456 V input swing.
KPD Series · 10–30 kVA
Contact-Type Voltage Stabilizer
±1% precision from a carbon-brush autotransformer.
SVC-T Series · 10–100 kVA
Three-Phase Voltage Stabilizer
Independent phase regulation for unbalanced three-phase loads.
Questions from project buyers.
Project-specific answers. If your question is not here, send the load list and the site conditions.
Talk to an engineer What is the real power of a 10 kVA stabilizer?
At a 0.8 power factor, 10 kVA delivers 8 kW. At 0.9 PF, it delivers 9 kW. Confirm the load PF before sizing.
Can a 5 kVA stabilizer run an air conditioner?
A small 1–1.5 HP air conditioner may run within a 5 kVA stabilizer, but the starting current can be high. Check the starting current and the stabilizer overload capability.
Is a 30 kVA stabilizer three-phase?
It can be single-phase or three-phase. For a three-phase supply or a three-phase load, choose the three-phase SVC-T with independent phase regulation.
How much margin should I add?
Add 20–30% for growth and motor starting. For a load with a large motor, do a starting-current study instead of a fixed margin.
Can I use a 10 kVA stabilizer for a whole house?
If the measured load is below 8 kW and the largest motor start is manageable, yes. Add the air conditioners, pump, fridge, and electronics, and confirm the starting current of the largest motor.
Send the load list. We will return the configuration.
Tell us the kW, the backup time, the phase, and the site country. You will get a capacity recommendation, a battery configuration, and the model sheet.
- Capacity and topology recommendation
- Battery bank and runtime estimate
- Model sheet and commercial offer
Request a configuration and quotation
Send the load list, backup time, and site conditions. We will return a capacity recommendation, battery configuration, and commercial offer.