There are three categories that CNC spindle control fall into:

Manual Control

You turn the spindle on and off with a switch and adjust the speed with its own speed control.


Basic Control

The speed of the spindle is set manually by you.  The actual turning on and off of the spindle is controlled by the CNC system.


Full Control

With full control, the CNC system can set the speed of the spindle and turn it on and off.

In this section I will show you how to gain basic control with a relay.


G540 Controlled Relay

The MASSO cannot control a relay directly with the M3/M5 commands. 

The G540has two built-in relay drivers. In my KRMx02 upgrade workbook I take you step by step through connecting a 48V relay to the G540. Those connections are the same.

The difference is that you will wire the MASSO spindle pin 2 (Spindle CW TTL Control) to pin 17 on the G540 DB25 connector.

When the MASSO does a M3 command the relay connected to the G540 will energize.

This is the way to go if you already have the relay and socket outlined in the upgrade workbook.


MASSO Controlled Relay Board

Shown here is a 30Amp Relay board driven by a low level TTL signal.

The board is powered from you 5V terminal blocks and your ground terminal blocks.

The MASSO (Spindle Pin 2) is then wired to the relay input.  Note that this relay board requires the small jumper wire between the VRef and DC- terminals.

The M3 command will engize the relay.


Wiring the Router

Wiring the router is very easy.

  1. Purchase a three prong extension cord.
  2. Cut the cord in half.
  3. Strip about 3" of the outer insulation from the cord.
  4. Remove about 1/2" of insulation from the six exposed wires. (Three on each cord)
  5. Twist the two white wires together and secure with Twist Connectors.
  6. Twist the two green wires together and secure with Twist Connectors.
  7. Wire one of the black wires to the common relay contact.
  8. Wire the other black wire to the NO relay contact.

Now plug your router into the female end of the cord.  Plug the mail end of the cord into your AC power source (Wall outlet).  Switch on your router and set the speed.

When the MASSO issues an M3 command the relay will energize and close the contacts on the two black wires, thus completing the circuit and starting the router.