Opto: 1

    Opto: 9 Plasma THC

    Opto: 25 Spindle Encoder

    Opto: 26 Spindle Encoder

    Opto: 27 Spindle Encoder

    Opto: 35

    Opto: 36

    Opto: 37

    Opto: 38

    Opto: 39 Spindle CW

    Opto: 40 Spindle CCW

Identifying Optocouplers

• Inputs (Opto 1–8, 10–24): LTV-816 or KB817
• THC Input (Opto 9): SFH615A-2
• Spindle Encoder Inputs (Opto 25–27): SFH615A-2
• Estop (Opto 38): LTV-816 or KB817
• MPG Inputs (Opto 28–37): LTV-816 or KB817
• Spindle CW and CCW Outputs (Opto 39 and 40): LTV-816 or KB817

Sourcing Replacement Parts

Damaged optocouplers can be purchased from suppliers such as:

• Digi-Key (LTV-816)
• Newark Element14 (KB817)
• Mouser Electronics (LTV-816)

Testing Procedure for Inputs 1–24

1. Remove any wires connected to the input
2. Go to the F1 screen and observe the input state (HIGH or LOW)

3. Connect the positive (+ve) of the MASSO power supply through a 5.6K resistor to the input

    

• The input should change state (LOW to HIGH or HIGH to LOW)
• If the input changes, the optocoupler is working correctly
• If the input does not change, the optocoupler may need replacement

If replacing the optocoupler does not resolve the issue, refer to the advanced testing procedure

Testing Procedure for Spindle Encoder Inputs

1. Remove all encoder input wires
2. Go to the F1 screen
3. Connect the positive (+ve) of the MASSO power supply through a 5.6K resistor to the selected encoder input

• Encoder A should change the Signal-A input
• Encoder B should change the Signal-B input
• Encoder Z should change the Index input

If the input changes state, the optocoupler is working correctly. Replace only the faulty optocoupler if required.

Testing procedure for MPG Inputs

• Go to the F1 screen
• Rotate the MPG dial

The MPG-A and MPG-B signals should toggle between HIGH and LOW.

• Select each axis (X, Y, Z, A, B) on the pendant
• Confirm the corresponding axis input changes state
• Select resolution settings (1, 10, 100)
• Confirm the resolution inputs change accordingly

If the inputs respond correctly, the optocouplers are working. Replace only the faulty optocoupler if required.

Testing Procedure for Estop Input

• Opto 38 is used for the Estop signal
• Remove the wire connected to Estop 2
• Go to the F1 screen and ensure the input shows LOW and is not inverted
• Apply +ve through a 5.6K resistor to Estop 2

The input should change from LOW to HIGH. If it does, the optocoupler is working correctly.

Testing Procedure for CW and CCW Outputs

Refer to the Spindle troubleshooting guide for test procedures.

Replacement Process

• Identify the polarity of the optocoupler. Each optocoupler has a dot indicating pin 1
• Take a photo before removal if unsure
• Use long-nose pliers or tweezers to gently remove the optocoupler from its socket
• Insert the replacement optocoupler, ensuring all pins are correctly aligned and fully seated
• Power the system and test to confirm correct operation