Build Guide · Motor Control

Hand-Off-Auto

A selector that runs a motor manually (Hand), keeps it off (Off), or hands control to an automatic device (Auto).

Difficulty: IntermediateBuilds on: two-wire controlLesson: read the theory →

What you’re building

The selector sends power to the Hand path (straight to coil M) or the Auto path (through a device contact to coil M).

Add the parts
Click Power Source, Selector (H-O-A), a Float or Limit Switch (the automatic device), Coil, Contactor, and Motor.
Label coil and contactor
Coil = M, Contactor = M.
Feed the selector common
To wire, click the first terminal (it highlights), then click the second to connect them. Bring power to the selector’s common terminal.
Power Source L1 → Selector COM
Wire the HAND path
The selector’s first output (Hand / T1) goes straight to the coil — manual run, no conditions.
Selector T1 (Hand) → Coil A1
Wire the AUTO path
The selector’s second output (Auto / T2) goes through the automatic device to the same coil terminal. Now in Auto the motor follows the device.
Selector T2 (Auto) → Float/Limit Switch (left)
Float/Limit Switch (right) → Coil A1 (same point as Hand)
Finish the control and power
Complete the coil return and wire the motor.
Coil A2 → Power Source N
Power Source L1 → Contactor
Contactor → Motor
Motor → Power Source N
Energize and cycle the selector
Click Energize, then click the selector to step through HAND / OFF / AUTO. HAND = runs now; OFF = can’t run; AUTO = runs only when you operate the float/limit switch.

Tip: Both the Hand and Auto paths land on the same coil — the selector just chooses which route is allowed to energize it.

Follow the steps above with the trainer open in another tab.