What causes Okuma OSP alarm 8628?

Spindle cooling unit lubrication oil level genuinely low. Faulty oil level float switch in the spindle cooling unit tank. Oil leak in the spindlehead lubrication circuit draining the tank. Wiring or connector fault on the level normal signal.

How do I fix Okuma OSP alarm 8628?

1. Read the code number shown with the alarm: code None = M-spindle cooling unit oil level normal signal OFF for more than 3 seconds while the unit was ON.; code 1 = Spindle cooling unit oil level normal signal OFF for more than 3 seconds while the unit was ON. 2. Read the code: no code means the M-spindle cooling unit oil level normal signal stayed OFF over 3 seconds; code 1 means the (main) spindle cooling unit oil level normal signal stayed OFF over 3 seconds, so you know which tank to check. 3. Open the sight glass or dipstick of the indicated spindle cooling unit tank and confirm the actual lubrication oil level; top up with the specified spindle oil if low. 4. If the oil level dropped, inspect the spindlehead lubrication lines, fittings and the cooling unit for leaks before refilling. 5. If the level is actually normal, test the float level switch for free movement and continuity and check its wiring back to the NC input. 6. Run the spindle cooling unit and watch the level normal signal on the input monitor to confirm it stays ON for more than 3 seconds without fluttering.

Okuma OSP codes

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Okuma OSP Controller

Lubrication · Intermediate

Alarm 8628

Okuma OSP Alarm A 8628 - Spindlehead lib oil level low

The oil level normal signal from a spindlehead (spindle) cooling/lubrication unit stayed OFF for more than 3 seconds while the unit was running, meaning the lubrication oil level is low. The spindle is stopped to protect the spindlehead bearings from running without lubrication.

Okuma OSPLubricationIntermediate

8628

Okuma OSP Alarm A 8628 - Spindlehead lib oil level low

Spindlehead lib oil level low

Common Causes

Spindle cooling unit lubrication oil level genuinely low
Faulty oil level float switch in the spindle cooling unit tank
Oil leak in the spindlehead lubrication circuit draining the tank
Wiring or connector fault on the level normal signal

Troubleshooting Steps

1Read the code number shown with the alarm: code None = M-spindle cooling unit oil level normal signal OFF for more than 3 seconds while the unit was ON.; code 1 = Spindle cooling unit oil level normal signal OFF for more than 3 seconds while the unit was ON.
2Read the code: no code means the M-spindle cooling unit oil level normal signal stayed OFF over 3 seconds; code 1 means the (main) spindle cooling unit oil level normal signal stayed OFF over 3 seconds, so you know which tank to check.
3Open the sight glass or dipstick of the indicated spindle cooling unit tank and confirm the actual lubrication oil level; top up with the specified spindle oil if low.
4If the oil level dropped, inspect the spindlehead lubrication lines, fittings and the cooling unit for leaks before refilling.
5If the level is actually normal, test the float level switch for free movement and continuity and check its wiring back to the NC input.
6Run the spindle cooling unit and watch the level normal signal on the input monitor to confirm it stays ON for more than 3 seconds without fluttering.

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