How Many Amps Does a JCW1325 CNC Machine Use?
A JCW1325 router is a 3-axis, 1300 × 2500 mm machine sold with several spindle options, so the current draw is not one fixed number. This guide shows how to read the nameplate, separate spindle amps from vacuum pump amps, and size the breaker and cable for your shop. It is written for maintenance engineers and shop owners who need a real figure before running conduit or buying a generator.
Key takeaways
What Determines JCW1325 CNC Machine Amps
A JCW1325 is a gantry router with a 1300 × 2500 mm working area. The frame, gantry and control cabinet are largely the same across builds. What changes is the spindle, and that is what moves the number most. A 3 kW air-cooled spindle at 380 V draws roughly 6 A at full load. A 9 kW unit at the same voltage draws roughly 16 A. Multiply by the voltage and you get the same kW figure, which is why the kW rating is the honest starting point.
Voltage matters as much as power. A 3 kW spindle on 220 V single-phase needs around 14 A. On 380 V three-phase it needs around 6 A per phase. If you are comparing quotes from two suppliers and one lists amps without stating voltage, the figure is meaningless. Ask for the full-load current at the supply voltage you actually have.
The nameplate on the spindle motor is the source of truth. It lists voltage, frequency, rated current and power factor. The machine's main data plate lists total connected load, which includes drives, servo motors, the control cabinet and any built-in pump. Use the main plate for breaker sizing, and the spindle plate when you are checking whether a specific spindle is available on your supply.
- 1Spindle kW ratingThe single biggest factor in current draw.
- 2Supply voltage and phaseSame power at higher voltage means lower amps.
- 3Auxiliary equipmentVacuum table, dust collector and chiller are often separate circuits.
Loads That Share the Circuit
Most JCW1325 installations are not a single plug. The router sits on one circuit, the vacuum pump on a second, and the dust collector on a third. On many shop floors all three land on the same subpanel, so the electrician sizes the feeder on the sum, not on the router alone. A 7.5 kW vacuum pump can draw 15 A at 380 V three-phase. A 3 kW dust collector adds another 6 A. That is 21 A of load that has nothing to do with the spindle.
Chillers are a quieter problem. A spindle chiller for a 9 kW water-cooled unit typically draws 1–2 A, which looks harmless. But it runs continuously, and it runs while the spindle is cutting. If you put it on the same circuit as the control cabinet, you have added a permanent load to a circuit that was sized for intermittent servo peaks.
The control cabinet itself is small. Servo drives, the controller, the VFD and the 24 V supply together usually draw under 5 A at 380 V. The servo motors peak during rapid moves and acceleration, and those peaks are short. They still count toward the breaker's instantaneous trip threshold, which is why an undersized breaker can trip during a fast G0 move even when the average current looks fine.
Single-Phase vs Three-Phase Supply
Small JCW1325 builds are sometimes ordered with a 220 V single-phase spindle for shops without three-phase power. That works, but the amps go up sharply. A 3 kW spindle at 220 V single-phase draws around 14 A at full load, and startup inrush can momentarily reach several times that. The wiring, breaker and plug all have to handle the inrush, not just the running current.
Three-phase is the better choice when it is available. At 380 V three-phase, the same 3 kW spindle draws around 6 A per phase. Cable sizes drop, heat drops, and the VFD runs cooler. If your shop has 415 V three-phase, current drops further. The machine's VFD usually accepts a range, but the spindle motor rating must match the nameplate voltage.
Do not assume a single-phase machine can be reconnected to three-phase later. The spindle motor, VFD and control transformer are all matched to the supply. Converting means replacing the spindle and the drive. If there is any chance you will move to a three-phase shop, order the three-phase build from the start.
How to Work Out the Amps for Your Machine
Follow these steps in order before you order cable or a breaker.
- 1Photograph the main data plateFind the plate on the control cabinet or machine frame. Record voltage, phase, frequency and total connected load in kW. If the plate is missing, ask the supplier for the electrical drawing.
- 2Record the spindle nameplateNote the spindle kW rating, voltage and rated current. A 3 kW unit at 380 V is typically around 6 A; a 9 kW unit is around 16 A. Write down the exact figure from the plate, not a rounded one.
- 3List every auxiliary loadVacuum pump, dust collector, chiller, air dryer. Get the kW or amp rating for each. Add them to the spindle and cabinet load.
- 4Convert everything to amps at one voltageUse A = kW × 1000 ÷ (V × 1.732 × power factor) for three-phase, or A = kW × 1000 ÷ (V × power factor) for single-phase. A power factor of 0.85 is a reasonable working figure for a spindle.
- 5Apply the 80% continuous ruleA breaker should carry no more than 80% of its rating on a continuous load. If your calculated total is 40 A, choose a 50 A breaker, not a 40 A one.
- 6Check voltage drop over the cable runKeep voltage drop under 3% on the feeder. Long runs to a rear workshop often need one cable size larger than the amp figure alone suggests.
- 7Verify the earth and neutralThree-phase machines need a proper protective earth. Do not rely on the conduit as an earth path. Confirm the neutral is sized for the control cabinet load.
- 8Test before productionClamp the incoming phases during a dry run and a light cut. Compare against your calculation. If measured current is more than 10% above the plate figure, stop and find out why.
Typical Full-Load Current by Configuration
Indicative figures for a JCW1325 router. Always confirm against the machine data plate.
| Configuration | Spindle load | Typical auxiliaries | Feeder sizing note |
|---|---|---|---|
| 3 kW spindle, 220 V 1-phase | ~14 A | Vacuum pump, dust collector | Split auxiliaries onto their own circuits |
| 3 kW spindle, 380 V 3-phase | ~6 A per phase | Vacuum pump, dust collector | Feeder usually set by auxiliary loads |
| 7.5 kW spindle, 380 V 3-phase | ~14 A per phase | Vacuum pump, chiller, dust collector | Size feeder on total, not spindle alone |
| 9 kW spindle, 380 V 3-phase | ~16 A per phase | Vacuum pump, chiller, dust collector | Confirm cable size for the full run length |
| 9 kW spindle, 415 V 3-phase | ~15 A per phase | Vacuum pump, chiller, dust collector | Lower current, same cable rules apply |
Size the circuit on the total, not the spindle
The amps a JCW1325 draws is the sum of spindle, cabinet, vacuum pump, dust collector and chiller. Measure each one, apply the 80% continuous rule, and check voltage drop over the actual cable run.
Frequently asked questions
Can I run a JCW1325 on a 32 A single-phase supply?
Only if the spindle is a small single-phase unit and the vacuum pump and dust collector are on separate circuits. A 3 kW single-phase spindle at 220 V draws around 14 A running, and inrush on startup is higher.
A 32 A breaker with a 3 kW spindle and a shared vacuum pump leaves very little headroom. Most shops with this setup end up upgrading the supply.
Why does my breaker trip during rapid moves?
Servo acceleration draws a short, high current peak. If the breaker is already close to its continuous limit because of shared auxiliary loads, that peak pushes it over the instantaneous trip threshold.
Move the vacuum pump and dust collector to separate circuits, and check that the breaker curve suits a motor load rather than a resistive one.
Does spindle type change the amps?
Yes. An air-cooled spindle and a water-cooled spindle of the same kW rating draw similar current at the motor, but the water-cooled unit adds a chiller that runs continuously.
The chiller is usually 1–2 A, which is small but permanent. Include it in the total when you size the feeder.
What cable size should I run to the machine?
That depends on the calculated total current and the length of the run. A 40 A total on a short run may suit one cable size; the same current over 30 m may need the next size up to keep voltage drop under 3%.
Let a qualified electrician confirm the cable against your local code. The amp figure alone is not enough to pick a cable.
Do I need a separate circuit for the vacuum table?
In most installations, yes. The vacuum pump is a large motor load that runs for long periods. Putting it on the same circuit as the router makes both harder to protect.
Separate circuits also make fault-finding simpler. If the breaker trips, you know which load caused it.
Is the amps figure the same for a 1300 × 2500 mm and a 1300 × 1300 mm machine?
The table size has little effect on current draw. The spindle, the servo motors and the auxiliary equipment set the load.
A longer machine may have larger servo motors for the extra gantry mass, but the difference is small compared with the spindle rating.
Need the electrical drawing for your build?
Send us your spindle choice and supply voltage. We will confirm the full-load current and the connected load for the machine before you run cable.
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