The Use Case

A cabinetry business operates in a remote location with only single‑phase 120/240 V service. Their equipment list includes a wide‑belt sander (≈18 HP), a large dust collector (≈12 HP), an air compressor (≈10 HP), and several CNC routers ranging from 15 to 20 HP each. The total simultaneous three‑phase load can approach 40 HP when multiple machines run together. The owner needs a converter that can handle this aggregate demand while maintaining voltage quality for the compressor and dust collector.

What Usually Matters for Sizing

  1. Sum of nameplate HP – add up all motors expected to run at once; in this case ≈ 40 HP.
  2. Full‑load amps (FLA) & locked‑rotor amps (LRA) – especially critical for the compressor and dust collector, which have high LRA values.
  3. Compressor‑duty considerations – Phoenix’s AutoLink or compressor‑duty NLA/PLA models provide better voltage regulation under fluctuating loads; avoid bare NL/PL SKUs for these applications.
  4. Starting sequence – staggered starts reduce surge demand, but the converter should still be sized for worst‑case simultaneous start of two large machines.
  5. Voltage level – most woodworking equipment runs on 230 V three‑phase; a converter that outputs this voltage directly simplifies wiring.

Common Mistakes to Avoid

  • Using only continuous HP for sizing – ignoring LRA can cause the converter to trip during compressor start.
  • Selecting a bare NL/PL unit for HVAC/compressor loads – leads to poor voltage balance and premature motor wear.
  • Undersizing transformer capacity – if you need to step up from 240 V single‑phase to 460 V three‑phase, the transformer must be rated for the full load current.
  • Forgetting future expansion – many shops add another router later; failing to include a margin forces a second converter purchase.

Practical Phoenix Recommendation

The support call (E102) shows the shop currently has a 40 HP converter but is hitting limits when adding more machines. The recommended upgrade is the GP100NLA, a 100 HP rotary phase converter with AutoLink/compressor‑duty capability. This model delivers ample headroom for the existing 40 HP load plus future expansion, and its built‑in voltage regulation protects the compressor and dust collector.

Install the GP100NLA on a dedicated 240 V, 200 A three‑phase input (using two 120 V legs) with appropriately sized conductors (#3/4 AWG copper). Use Phoenix’s AutoLink configuration to connect the air compressor and dust collector, ensuring stable voltage during start‑up. If any equipment requires 460 V, add a step‑up transformer downstream of the converter; otherwise, wire directly for 230 V three‑phase.

What to Have Ready Before Calling

  • Complete equipment list – nameplate HP, voltage, FLA, LRA for each machine.
  • Desired simultaneous load – which machines will run together during peak operation.
  • Single‑phase service capacity – available amperage and breaker sizes on the main panel.
  • Future purchase plans – any additional routers or sanders you anticipate adding.
  • Space and ventilation – dimensions for the GP100NLA and clearance for airflow.

> Final note: Always verify the final converter rating against each motor’s nameplate data (HP, voltage, LRA/FLA) and the expected starting behavior. Selecting a Phoenix rotary phase converter with AutoLink/compressor‑duty capability ensures reliable power for demanding woodworking shops without unnecessary downtime or costly upgrades.