Which accessories does a VFD need
A variable frequency drive out of the box is just the foundation. For proper operation on site you need additional components: protection, filtering, control, communication. Which ones depends on the application. We have split everything into a minimum kit (do not power on without it) and a recommended kit (for reliable operation over years).
Minimum kit: essentials
- Circuit breaker — mandatory before the VFD. Rating 1.5-2x the VFD rated current. C or D curve.
- Contactor (if needed) — when the VFD must be disconnected remotely or by a safety signal.
- Cables of correct cross-section — power cable from mains to VFD and from VFD to motor.
This is the minimum. Do not power on a VFD without a circuit breaker.
Recommended kit
| Accessory | Purpose | When needed | Approx. price |
|---|---|---|---|
| Braking resistor | Fast motor braking | Cranes, conveyors, centrifuges | 800-5,000 UAH |
| Braking module | External chopper for VFDs from 11 kW | VFDs without built-in chopper | 3,000-15,000 UAH |
| EMC filter | Protect mains from VFD noise | Residential, medical sites | 1,500-15,000 UAH |
| Line reactor | Protect VFD from voltage spikes | VFDs from 15 kW, unstable mains | 1,200-8,000 UAH |
| Remote panel | Control VFD from a distance | VFD in locked cabinet | 800-5,000 UAH |
| Shielded cable | Reduce EMC radiation | Sensitive equipment nearby | 150-300 UAH/m |
What to choose by application
Pump / fan
Simplest case. Minimum kit plus line reactor (for VFDs from 15 kW). Braking resistor usually not needed. EMC filter if the pump room is in a residential basement.
Conveyor / packaging line
Minimum plus braking resistor. EMC filter if scales or sensors are nearby. Remote panel if the operator is far from the cabinet.
Crane / elevator / hoist
Full kit: braking resistor + braking module + line reactor + EMC filter + shielded cable.
Woodworking / cutting machines
Braking resistor is mandatory. Line reactor if several VFDs share one cabinet. EMC if CNC is nearby.
Kit costs: real numbers
| VFD power | Minimum kit | Recommended | Full |
|---|---|---|---|
| 4 kW | ~500 UAH | ~3,000 UAH | ~6,000 UAH |
| 15 kW | ~1,200 UAH | ~6,000 UAH | ~14,000 UAH |
| 37 kW | ~2,000 UAH | ~12,000 UAH | ~25,000 UAH |
A full accessory kit typically adds 15-30% to the VFD cost.
Frequently Asked Questions
Can a VFD run without any accessories?
With just a circuit breaker — yes, for simple tasks like a fan. But even then a line reactor is recommended for VFDs from 15 kW.
Which accessories sell most?
Braking resistor and remote panel lead. EMC filter is third — often installed after the first interference complaints.
Can accessories be added later?
Yes, all accessories are retrofittable. But shielded cable is better laid from the start.
Do you sell ready-made kits?
We select individually by application. Call or message us — we will recommend the right set.
Is a fuse needed if there is a circuit breaker?
For VFDs up to 30 kW a circuit breaker is usually enough. For higher power — a semiconductor fuse is recommended.
Summary
Minimum is a circuit breaker and cables. Recommended — add what your application needs: braking resistor, EMC filter, reactor, panel.
All accessories for variable frequency drives are in our catalogue. Contact us and we will put together a kit for your site.
