This procedure tells you how to perform these tasks:

1. Remove a shafted optical-encoder.
2. Install a shafted magnetic-encoder.

Do not perform this procedure for an encoder with a hub. If you have an encoder with a hub perform this procedure:

40/50-Taper Spindle - Hubbed Encoder - Replacement.

Jog the spindle to a position that gives easy access to the spindle motor.

 Note: 

• For a 40-Taper machine without a gearbox, the encoder is on the top of the spindle motor.
• For a 40-Taper machine with a gearbox, the encoder is on the bottom of the spindle motor.

Press [POWER OFF].

Set the main circuit breaker to the OFF position.

Lock the main circuit breaker.

Use an approved lock with an approved safety tag.

Remove the spindle head covers as necessary.

Remove the encoder connector [1] from the encoder [2].

Loosen the (4) tension bracket screws [1].

Make sure the tension bracket screws [1] are sufficiently loose to let you move the encoder tension bracket assembly [2].

Move the encoder tension bracket assembly [2] in the direction of the motor encoder pulley [3].

Remove the encoder belt [4].

Remove the (4) tensioner screws [1].

Remove the encoder tension bracket assembly [2].

Remove the encoder [7] and encoder screws [6] from the encoder belt tensioner [5].

 Note: Some encoders can have nuts.

Remove the pulley screw [9].

Remove the pulley [8] from the encoder [7].

 Note: No pulleys are included with the new encoder [1].

Apply the correct thread-locking compound ("Loctite") to the setscrew.

Install the pulley [2] on the encoder [1].

Make sure the pulley [2] is in the same position on the shaft as on the used encoder.

Install the pulley screw [3].

Install the encoder [1] and screws [4] on the encoder belt tensioner [5].

 Note: Some encoders can have nuts.

Install the encoder tension bracket assembly [6].

Install the (4) tensioner screws [9]. Tighten the tensioner screws [9] with your hand.

Make sure the tensioner screws [9] are sufficiently loose to let you move the encoder tension bracket assembly [6].

Move the encoder [1] in the direction of the motor encoder pulley [7].

Put a new encoder belt [8] on the encoder pulleys [7]. Use your hand to turn the spindle.

Turn the spindle to align the belt [8] with the pulleys.

Remove the (3) encoder cover screws and washers.

Remove the top of the encoder.

Connect the adaptor cable [1] to the circuit card [2].

Install the encoder cap.

 Caution: Before you tighten the screws, make sure the cable is in the slot on the cap. This prevents damage to the cable.

Install the (3) encoder cover screws and washers.

Connect the adaptor cable [4] to the encoder connector [3].

Unlock the main circuit breaker.

Press [POWER ON].

Update the parameter values.

 Note: Make sure the parameters are correct. Refer to 40/50-Taper Spindle - Shafted Encoder - Installation Aid

Press [ZERO RETURN].

Press [ALL].

Operate this code in MDI mode:

S500 M03 ;

This code [1] turns the spindle at 500 RPM.

This lets the spring apply the correct tension to the belt.

 Caution: Make sure the belt tension is correct. The maximum radial load (side load) for the encoder shaft is 13 1/2 lbs (60 Nm). Too much tension can cause damage to the encoder. Some machines have a belt-tension bracket that is automatic.

Press [RESET] to stop the spindle.

Press [EMERGENCY STOP].

Tighten the (4) tension screws.

Jog the spindle to a position that gives easy access to the spindle motor.

Press [POWER OFF].

Set the main circuit breaker to the OFF position.

Lock the main circuit breaker.

Use an approved lock with an approved safety tag.

Remove the spindle head covers as necessary.

Remove the encoder connector [1] from the encoder [2].

Loosen the (4) tensioner screws [2].

Make sure the tension bracket screws [2] are sufficiently loose to let you move the encoder tension bracket assembly [1].

Move the encoder tension bracket assembly [1] down in the direction of the spindle pulley.

Remove the encoder belt.

Remove the (2) mounting screws [3].

Remove the encoder tension bracket assembly [1].

Remove the (4) encoder screws [4].

 Note: Some encoders can have nuts.

Remove the encoder [5] from the belt tensioner [6].

Remove the pulley screw [8].

Remove the pulley [7] from the encoder.

 Note: No pulleys are included with the new encoder [1].

Apply the correct thread-locking compound ("Loctite") to the setscrew.

Install the pulley [2] on the encoder [1].

Make sure the pulley [2] is in the same position on the shaft as on the used encoder.

Install the pulley screw [3].

Install the encoder [1] and screws [4] on the encoder belt tensioner [5].

 Note: Some encoders can have nuts.

Install the encoder tension bracket assembly [6].

Make sure the tensioner screws [8] are sufficiently loose to let you move the encoder tension bracket assembly [6].

Install the (2) mounting screws [7].

Move the encoder tension bracket assembly [6] in the direction of the motor encoder pulley.

Put a new encoder belt on the encoder pulleys. Use your hand to turn the spindle.

Turn the spindle to align the belt with the pulleys.

Remove the (3) encoder cover screws and washers.

Remove the top of the encoder.

Connect the adaptor cable [1] to the circuit card [2].

Install the encoder cap.

 Caution: Before you tighten the screws, make sure the cable is in the slot on the cap. This prevents damage to the cable.

Install the (3) encoder cover screws and washers.

Connect the adaptor cable [3] to the encoder connector [4].

Unlock the main circuit breaker.

Press [POWER ON].

Make sure the parameters are correct.

 Note: Refer to 40/50-Taper Spindle - Shafted Encoder - Installation Aid

Press [ZERO RETURN].

Press [ALL].

Operate this code in MDI mode:

S500 M03 ;

This code turns the spindle at 500 RPM.

This lets the spring apply the correct tension to the belt.

 Caution: Make sure the belt tension is correct. The maximum radial load (side load) for the encoder shaft is 13 1/2 lbs (60 N). Too much tension can cause damage to the encoder. Some machines have an automatic belt-tensioning bracket.

Press [RESET] to stop the spindle.

Press [EMERGENCY STOP].

Tighten the (4) tensioner screws [1].

Operate the spindle at 25% [1], 50% [2] and 100% [3] of maximum speed.

 Note: In this example the maximum speed is 7500 RPM.

Make sure the spindle speed in the code [1] is the same as the spindle speed on the display [2].

If these spindle speeds are not the same, make sure the encoder parameters are correct.

Repeat step 1.