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08 Technical Service · Automotive connector OEM

Elimination of false rejects in contaminated leak test equipment

Sentinel A28 False rejects Air quality CKD filters

A Sentinel A28 unit had internal contamination from dust and water. All parts were being rejected for supposed leaks — false rejects that were affecting production. Lübeck repaired the unit the same day and loaned a temporary unit to keep the line from stopping.

Client
Automotive connector OEM
Automotive electrical connections
0
False rejects post-intervention
+1 year
Stable operation without additional repairs
48
Units in recurring calibration with Lübeck
1 day
Complete repair + loaner equipment
// 01 · Challenge

The unit was rejecting all parts — but the parts had no leak

The client manufactured automotive electrical connections with high quality and repeatability requirements. A Sentinel A28 unit had internal contamination from dust and water accumulated in the pneumatic circuit. As a result, the instrument detected leaks where there were none — generating false rejects on 100% of the parts.

Internal contamination from dust and water in the Sentinel A28
100% of parts rejected — false rejects
Production affected by lack of reliable equipment
Compressed air quality insufficient for leak test instrumentation
// 02 · Solution

Repair, loaner equipment, and preventive improvement — all the same day

Comprehensive intervention: Lübeck repaired the unit, loaned a temporary one so the line wouldn't stop, and resolved the root cause by installing proper filtration.

1

Specialized corrective maintenance

Internal pneumatic circuit cleaning and complete repair of the Sentinel A28 unit. Elimination of dust and water contamination.

2

Temporary loaner equipment

To avoid line stoppage during the repair, Lübeck loaned a functional unit to the client. Operational continuity guaranteed.

3

CKD filter train

Installation of a CKD filter train to improve compressed air quality feeding the instrument — preventive solution that attacks the root cause of contamination.

4

Same-day repair

Equipment repaired and returned operational in the same shift. No additional days of production impact.

// 03 · Result

Zero false rejects. +1 year stable. 48 units in calibration.

Total elimination of false rejects — the unit returned to precise measurement.
Immediate production recovery — no additional days of downtime.
+1 year of stable operation without need for additional repairs. Maintenance limited to annual calibrations.
48 units in recurring calibration — the client transferred the calibration of their entire instrument fleet to Lübeck.

"The client continues to contact Lübeck for technical support, repairs, and specialized consultations, building a long-term trust relationship."

— Portfolio documentation, case 08
// Does your equipment give readings you don't trust?

False rejects
have a root cause.

If your leak test equipment rejects good parts or gives unstable results, we can diagnose the contamination, repair, and improve air quality — without changing equipment.