A diode laser, a CO2 cutter or an ultrasound machine can cost more than a car. Yet we often see one plugged into a cheap relay stabilizer, or an old servo that takes two seconds to react. When something fails, the stabilizer gets blamed — but the real mistake was the type.
Why these machines are different
A fridge or a fan does not mind a dip of a second or two. A laser, a CNC or a medical device does. Inside are switch-mode power supplies, control boards, motion drives and laser sources. A sudden dip can make them reset in the middle of a job, abort a treatment shot, spoil a cut or throw an error. A surge can damage the power supply.
These machines do not care that your average voltage is 220V. They care what happens in the first few milliseconds of a change.
Why a servo is the wrong tool here
- Too slow. A servo corrects at about 25–30 volts per second. A sudden 60V drop takes about two seconds to fix. The machine sees the dip.
- It wears. The carbon brush and motor need service — and service means downtime for the machine.
- It hums. Not what you want in a treatment room.
A relay stabilizer is faster but corrects in coarse steps and clicks every time. For a valuable machine, both are false savings. Solid-state is the right tool.
SCR or IGBT? A guide by machine
| Machine | Our usual suggestion | Why |
|---|---|---|
| Aesthetic and hair-removal lasers, dental lasers | SCR (IGBT if voltage falls below 95V) | Fast and silent; most accept ±10% |
| RF, HIFU and body-contouring devices | SCR | Steady, spark-free, quiet |
| Ultrasound, ECG, patient monitors | SCR, or IGBT for the cleanest wave | Fast correction; check the manual's tolerance |
| Lab analysers, PCR, centrifuges | IGBT | ±2% and a pure sine for instruments |
| CO2 laser cutters and engravers | IGBT | Laser supply and motion drives like a clean, tight supply |
| Single-phase CNC routers | IGBT | Stepper and servo drives, spindle electronics |
| Servers, network racks, broadcast | IGBT, with a UPS | Clean wave, no dips |
| Fibre laser cutters, large CNC, X-ray, CT, MRI | Talk to us | Often three-phase with high start-up current; sized to the maker's power spec |
For three-phase machines, see our industrial systems — available in static IGBT or servo, made to your load.
Read your machine's manual first
Find the page called "power requirements" or "electrical specifications". Look for four things:
- Input voltage — for example 220–240V.
- Tolerance — for example ±10%. If it says ±10% or wider, an SCR (±5%) keeps it well inside. If it says ±5% or tighter, choose IGBT (±2%).
- Power — the maximum input in VA, kVA or W. This is what you size from.
- Any note about a "regulated", "stable" or "clean" supply — choose IGBT.
How to size it
- Take the machine's maximum input power, not its average.
- Add everything that runs with it. A laser often has a water chiller. A CNC router has a vacuum pump and a dust extractor. A clinic room has an AC. These motors pull a surge when they start.
- Add 25–50% headroom on top. More if there are motors.
- Pick the next size up.
Not sure? Send us a photo of every nameplate and we will do the sum for you.
A stabilizer is not a UPS
A stabilizer fixes bad voltage. It does nothing when the power goes off. If a machine must not stop mid-job — a treatment shot, an analyser run, a server — put a UPS after the stabilizer: mains, then stabilizer, then UPS, then machine. The stabilizer protects the UPS; the UPS covers the outage.
Install it right
- A dedicated circuit from the board, with the right cable size.
- A proper earth. This matters most for medical and laser equipment. A stabilizer cannot fix a missing earth.
- No extension boards between the stabilizer and the machine.
- Space and air around the unit, away from the machine's own heat outlet.
What Voltec offers clinics and workshops
Voltec imports both solid-state types: the SCR range from 1 to 10 kVA and the IGBT range from 550VA to 20 kVA, plus three-phase systems for larger machines. We size from your nameplates, quote in writing, and back what we sell with our own service team. Clinic owners can also see our medical power protection page. For background, read SCR vs IGBT and our solid-state guide.
