1200

Check Hydraulic Pressure Gauge

Verify hydraulic system pressure at the main gauge. Normal operating pressure should be 500-700 PSI for most Okuma turret systems. If pressure is below 400 PSI, the turret cannot function properly.

Ensure machine is in emergency stop before checking hydraulic connections

Inspect Hydraulic Filter

Check the hydraulic filter for contamination. A clogged filter will cause pressure drop and slow turret response. Replace filter if dirty or if pressure differential exceeds manufacturer specifications.

Check filter bypass valve - if it's open, the filter is likely clogged

Test Turret Valve Operation

Access the PLC ladder logic through the maintenance screen and manually activate the turret clamp/unclamp valves. Listen for valve operation and observe pressure changes to isolate faulty solenoid valves.

Check Position Sensor Status

Navigate to DIAGNOSIS > I/O MONITOR and check the turret position sensor inputs. Look for sensors that remain ON or OFF regardless of turret position, indicating sensor failure or wiring issues.

Turret position sensors typically show as X inputs in the 100-120 range

Clean Sensor Faces

Clean all proximity sensors around the turret with contact cleaner and ensure proper gap (typically 1-2mm). Metal chips or coolant buildup can cause false readings or prevent sensor activation.

Power down machine before cleaning sensors to avoid accidental turret movement

Test Sensor Voltage

Using a multimeter, verify 24VDC supply voltage to each position sensor and check for proper switching when manually moving turret (in manual mode only). Replace any sensors showing incorrect voltage or no switching action.

Manual Turret Rotation Test

With hydraulic pressure off and turret unclamped, attempt to manually rotate the turret. It should move smoothly with moderate force. Binding, grinding, or excessive resistance indicates mechanical problems.

Ensure all axes are locked and spindle is stopped before manual turret manipulation

Inspect Curvic Coupling

Examine the curvic coupling teeth for damage, wear, or debris. Clean thoroughly with solvent and check for proper engagement. Damaged teeth prevent accurate positioning and can cause binding.

Look for metal particles in the coupling area - this indicates excessive wear

Check Turret Bearing Play

With turret clamped, check for excessive radial or axial play by attempting to move the turret by hand. Excessive movement indicates worn bearings that may prevent proper positioning repeatability.

Review Turret Timing Parameters

Access the PLC parameters through SETTING > PLC PARAMETER and locate turret timing values (typically T100-T110 range). Compare current values with machine documentation to ensure proper timeout settings.

Standard turret index timeout is usually 8-15 seconds depending on turret size

Monitor Actual Cycle Time

Use the PLC monitor function to time actual turret indexing cycles and compare with programmed timeout values. If actual time consistently approaches timeout, increase the timer value slightly.

Do not increase timeout values excessively as this masks real mechanical problems

Verify Sequence Logic

Check PLC ladder logic for proper turret indexing sequence. Ensure unclamp, rotate, and clamp signals follow correct order and timing. Look for modified or corrupted ladder logic that could affect timing.