What causes Okuma OSP alarm 8638?

Clamp command issued while the machine is in tailstock control mode (Code 1). Clamp command issued while the tailstock is at its advance position (Code 2). Clamp command issued while the W-axis is still in motion (Code 3).

How do I fix Okuma OSP alarm 8638?

1. Read the code number shown with the alarm: code 1 = Clamp command issued while in tailstock control mode; code 2 = Clamp command issued while tailstock is at the advance position; code 3 = Clamp command issued while the W-axis is moving 2. Read the code shown with the alarm to identify which condition blocked the clamp. 3. Code 1: the machine is in tailstock control mode — cancel tailstock control mode before issuing the sub-spindle head clamp command. 4. Code 2: the tailstock is at the advance position — retract the tailstock to its retract position, then re-issue the clamp command. 5. Code 3: the W-axis is moving — wait for W-axis motion to complete (in-position) before commanding the clamp; check the program for a clamp M-code placed before W-axis positioning finishes. 6. If the alarm returns after these checks, record the alarm number, code and object and contact Okuma service.

Okuma OSP codes

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Okuma OSP Controller

Spindle · Intermediate

Alarm 8638

Okuma OSP Alarm A 8638 - Sub-spindle head clamp condition

The control received a sub-spindle head clamp command while one of the required preconditions for clamping was not satisfied. Clamping the sub-spindle head under these conditions could damage the tailstock, W-axis drive, or workpiece, so the command is rejected.

Okuma OSPSpindleIntermediate

8638

Okuma OSP Alarm A 8638 - Sub-spindle head clamp condition

Sub-spindle head clamp condition

Common Causes

Clamp command issued while the machine is in tailstock control mode (Code 1)
Clamp command issued while the tailstock is at its advance position (Code 2)
Clamp command issued while the W-axis is still in motion (Code 3)

Troubleshooting Steps

1Read the code number shown with the alarm: code 1 = Clamp command issued while in tailstock control mode; code 2 = Clamp command issued while tailstock is at the advance position; code 3 = Clamp command issued while the W-axis is moving
2Read the code shown with the alarm to identify which condition blocked the clamp.
3Code 1: the machine is in tailstock control mode — cancel tailstock control mode before issuing the sub-spindle head clamp command.
4Code 2: the tailstock is at the advance position — retract the tailstock to its retract position, then re-issue the clamp command.
5Code 3: the W-axis is moving — wait for W-axis motion to complete (in-position) before commanding the clamp; check the program for a clamp M-code placed before W-axis positioning finishes.
6If the alarm returns after these checks, record the alarm number, code and object and contact Okuma service.

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