Traub TNE 300 A007: Missing NC Ready, Not a Hydraulic Diagnosis

The panel shows A007, translated as “NC operational readiness missing,” and the hydraulics switch off during machining. Start with the NC-ready chain: the alarm reports loss of readiness from the numerical control, while the hydraulic shutdown may be the machine’s response to that loss. Resetting hydraulic devices first can hide the sequence without identifying what removed NC readiness.

Read the symptom in the right order

Capture the panel state before resetting anything. The first event matters more than the loudest consequence.

If another NC alarm appears immediately before A007, troubleshoot that earlier alarm first. If A007 is the first recorded event, trace the NC-ready condition from the numerical control toward the machine control.

Trace how NC readiness drops the hydraulics

A CNC machine normally permits motion and machining auxiliaries only while several conditions remain valid. The numerical control completes its startup checks, enters a ready state, and communicates that state to the machine logic. The machine logic then combines NC readiness with safety, drive, lubrication, hydraulic, and mode interlocks.

When NC readiness disappears during a cycle, the machine logic can remove run permissions. A hydraulic contactor, valve command, or enable signal may then drop even though the hydraulic hardware did not initiate the event. That sequence protects clamping and motion functions from continuing after the CNC can no longer control the process.

The missing-ready condition can originate in several fault classes:

• An active NC alarm prevents the control from remaining operational.
• The NC subsystem loses control power or experiences an unstable supply.
• Communication between the NC and machine logic stops or becomes invalid.
• A drive, axis, spindle, or machine interlock causes the NC to withdraw readiness.
• A connector, relay contact, interface signal, or wiring path becomes intermittent under vibration or temperature change.
• The machine logic receives NC readiness but rejects another required permissive in the same stop chain.

The exact signal name, address, connector, and voltage depend on the installed control and machine documentation. Read those identifiers from the electrical drawings and diagnostic pages; do not substitute an identifier from a different machine.

Start with the first diagnostic checks

Start here. Preserve the event sequence, then separate an NC-originated stop from a hydraulic-originated stop.

1. Record every active alarm exactly as displayed, including alarms shown before and after A007. Photograph the pages if the control has no usable history.
2. Open the alarm history or diagnostic buffer without resetting the machine. Identify the first event at the shutdown, not merely the alarm left on the final screen.
3. Check whether the NC reports a ready, run, stopped, or faulted state. Look for an active NC, axis, spindle, drive, communication, or internal control alarm.
4. Use the machine diagnostics and electrical drawings to locate the NC-ready indication at both ends of the interface. Compare the NC’s transmitted state with the state received by the machine logic.
5. Inspect the related control-power supplies, protective devices, connectors, interface relays, and terminals. Look for loose connections, heat damage, contamination, or a supply that changes when the fault occurs.
6. Check the hydraulic status independently: pressure indication, oil level, temperature indication, motor command, overload state, and feedback interlocks. This establishes whether a hydraulic condition preceded the NC-ready loss or followed it.
7. Compare the machine state that triggers the failure: spindle start, axis movement, tool operation, clamping action, or another repeatable transition. A repeatable transition narrows the search to the permissions and loads that change at that point.

Use qualified electrical personnel for live measurements. Compare measured control power with the values printed in the machine drawings or on the applicable device; no universal voltage can be assigned from A007.

Restore readiness without masking the cause

Correct the earliest confirmed failure, then perform a controlled recovery.

1. Place the machine in a safe stopped condition and secure the workholding state before manipulating power or outputs.
2. Clear the initiating NC, drive, communication, power, or interlock fault. If the NC-ready signal is present at the source but absent at the receiver, repair the documented interface path instead of replacing hydraulic components.
3. If hydraulic pressure or feedback failed first, correct that condition and verify its input changes correctly. Treat A007 as a resulting readiness problem only after the event order proves it.
4. Reset alarms using the normal machine sequence. Avoid repeated resets when an alarm returns immediately; the unchanged diagnostic state is useful evidence.
5. Re-establish NC readiness before commanding hydraulics or cycle operation. Confirm that the machine logic recognizes the ready state.
6. Test in the least hazardous operating mode permitted by the machine instructions. Advance one function at a time until the original transition is reached.

A full power cycle is a diagnostic separator, not a repair. If cycling power temporarily restores operation, investigate control power, thermal behavior, connectors, communication, and controller diagnostics before returning the machine to production.

Verify the repair under the original conditions

A cleared panel is not enough. Verify the complete permission chain.

• A007 remains absent after the normal startup and reset sequence.
• The NC-ready indication stays present at the NC and at the machine-control receiver.
• The hydraulic command remains active, pressure and feedback remain valid, and no overload or temperature indication appears.
• The axes, spindle, clamping functions, and relevant auxiliaries complete their permitted checks without withdrawing readiness.
• The machine passes the same machining transition that produced the shutdown.
• The alarm history contains no new preceding fault, communication interruption, or power-related event.

If the problem is intermittent, record the machine state and diagnostic signals during several controlled repetitions. Stop testing if safe clamping, lubrication, braking, or controlled motion cannot be maintained.

Avoid the fixes that waste time

• Do not replace the hydraulic pump solely because the hydraulics switched off. Prove loss of pressure, motor command, feedback, or another hydraulic fault first.
• Do not treat A007 as the initiating fault when an earlier NC or drive alarm exists. The first event controls the troubleshooting path.
• Do not bypass the NC-ready, safety, pressure, or machine interlocks. A bypass destroys the event sequence and can permit unsafe motion or loss of workholding.
• Do not cycle power before recording diagnostics. Volatile status can disappear during restart.
• Do not copy signal addresses or wiring details from another TNE 300 without matching the installed control, electrical drawing revision, and machine configuration.
• Do not return the machine to automatic operation after a reset-only recovery. Reproduce the original load and transition under controlled conditions.

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