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Fault finding

RTP20

CAUTION: RTP20 is designed for automated operation under direct control of the CMM software. To avoid possible collision during use, RTP20 must not be unlocked, re-orientated or locked by hand during normal operation.

Poor measuring performance

Possible causes

Remedy

Loose mounting

Ensure shank mounting screws are tight and mounting to CMM is secure.

Problem with TP20 probe module

Diagnosis of the probe unit should be carried out with axes correctly locked an without head adjustment between probe points.

Problem with swivelling / indexing unit

Diagnosis of the indexing unit should only be carried out following satisfactory probe performance.

No probe signal and / or no probe status LED

Possible causes

Remedy

Cable faulty / not connected

Check continuity of cabling from head to interface / machine control.

Probe interface faulty / not connected

Ensure correct connection of interface / machine control.

Poor repeatability (RTP20 only)

Possible causes

Remedy

Axes lock procedure incorrect

Using automated cycle ensure lock lever is fully rotated to lock position.

Axes unlock procedure incorrect

Using automated cycle ensure lock lever is fully rotated into unlock position during indexing.

Forces imparted onto head during lock-up

Using automated cycle unlock and re-lock.

Attempted lockup in incorrect unqualified position

Using automated cycle unlock, reposition correctly and re-lock.

Axes ‘rattling' during indexing (RTP20 only)

Possible causes

Remedy

Incorrect unlock procedure

Using automated cycle ensure lock lever is fully rotated to unlock position.

Incorrect indexing procedure

Using automated cycle index each axis separately.

NOTE: The RTP20 is not user serviceable and should be returned to Renishaw if suspected faulty.

TP20

Poor measuring performance

Possible causes

Remedy

Stylus configuration too long or not rigid

Use shorter stiffer stylus configuration.

Poor stylus assembly

Ensure stylus joints are kept to a minimum and the joints are clean and secure.

Contamination / damage to stylus ball

Inspect for damage, clean thoroughly with solvent.

Trigger force too high.

Use lower force module.

Unwanted triggering during probe or CMM movement

Possible causes

Remedy

Trigger force too low / stylus configuration to heavy

Use higher force module / reduce mass of stylus configuration.

Probe fails to rearm after trigger

Possible causes

Remedy

Trigger force too low / stylus configuration too heavy

Use higher force module / reduce mass of stylus configuration.

Probe reseat failure

Re-trigger probe. If problem persists please return to Renishaw for service.

 Loss of measuring accuracy

Possible causes

Remedy

Mounting not secure

Check that the RTP20 is correctly mounted on the shank and that the screws are secure.

Check clamping mechanism in the CMM quill is secure for RTP20.

RTP20 not fully locked

Ensure that the thumbwheel / lock lever is turned fully clockwise.

Force imparted to probe module after locking

Re-qualify the probe.

RTP20 worn or damaged

Use only with the specified probe and extension combinations.

Faulty probe module

Check by substitution or return to Renishaw or your supplier.