2-1721142-6 Cross-Reference Verification and Procurement Checklist
The 2-1721142-6 is an electromechanical relay manufactured by TE Connectivity Potter & Brumfield Relays, categorized under Electronic Component in the distributor’s database. Engineers and procurement professionals sourcing this part face risks from counterfeit, refurbished, or mislabeled units because the PCJ-112D3MH 301Y marking is easily replicated on low-cost fakes. This article provides a hands-on verification protocol covering visual inspection, electrical parameter measurement, X-Ray analysis for high-reliability deployments, packaging audit, and sampling plans.
Visual and Marking Inspection: Laser-Etch vs. Ink and Lot Decoding
The PCJ-112D3MH 301Y marking on genuine 2-1721142-6 units is applied via laser etching, producing a sharp, slightly recessed, gray-white mark that does not smudge when rubbed with isopropyl alcohol. Counterfeit units often use inkjet or pad printing, which appears glossy, sits proud of the plastic surface, and can be partially removed with solvent. Inspect the text alignment: genuine markings have consistent spacing and no bleeding at character edges. Use a 10x loupe or digital microscope to verify.
Decode the lot code using the YYWW format (year and work week). For example, a marking reading “2308” indicates production in week 8 of 2023. Compare this against the expected age of stock in your supply chain. Units marked with codes older than 36 months may have aged-out relay contacts (increased contact resistance) and should be electrically tested before acceptance. If the lot code is absent or uses an unfamiliar format (e.g., four-digit numeric without YYWW logic), flag the batch for deeper investigation.
Cross-reference the sibling parts listed in the database—1-1721142-9, 1423685-1, 1721083-1, 1-1393161-7, 1393186-9, 1461077-2, 5-1440000-7, 5-1393222-6, 4-1419144-4, and 1393186-5—to confirm package dimensions and pin configurations. Any deviation in body dimensions of more than 0.2 mm from the typical PCJ-112D3MH outline should trigger rejection.
Parameter Measurement Methods and Pass-Fail Criteria
Due to the absence of specific datasheet values in the procurement database, engineers must derive acceptance criteria from the product family characteristics. The PCJ series from TE Connectivity Potter & Brumfield Relays typically operates with coil voltages of 12 VDC or 24 VDC and switching currents up to 30 A. Use the following instruments and thresholds.
| Parameter | Value | Engineering Meaning |
|---|---|---|
| Coil Resistance (Ω) | Consult the latest 2-1721142-6 datasheet | This parameter indicates the coil winding integrity; deviation >±10% from nominal suggests insulation damage or counterfeit winding material. |
| Pick-Up Voltage (VDC) | Consult datasheet | Minimum voltage at which the relay switches; values above 75% of nominal coil voltage indicate mechanical binding or magnetic circuit defects. |
| Drop-Out Voltage (VDC) | Consult datasheet | Voltage at which contacts release; values below 10% of nominal may indicate residual magnetism or welded contacts. |
| Contact Resistance (mΩ) | Consult datasheet | Measures path integrity through closed contacts; typical range for fresh relays is 10-50 mΩ. Readings >100 mΩ suggest oxidation or contamination. |
| Insulation Resistance (MΩ at 500 V) | Consult datasheet | Test between coil and contacts; >100 MΩ is typical for clean relays. Lower values imply moisture ingress or carbon tracking. |
| Operate Time (ms) | Consult datasheet | Delay from coil power to contact closure; values exceeding 20 ms may suggest sluggish armature movement. |
| Release Time (ms) | Consult datasheet | Time from coil removal to contact break; unusually fast release can indicate damaged return springs. |
| RoHS Status | — | Specialty parameter — see datasheet for compliance confirmation. |
When measuring pick-up voltage, apply a ramp from 0 V to nominal coil voltage at 1 V/s using a programmable DC supply and a digital oscilloscope to capture the transitionpoint. For contact resistance, use a four-wire Kelvin probe with a 100 mA test current to avoid heating the contacts. Set the pass-fail boundary at 10% above the datasheet maximum; if no datasheet is available, use the worst-case values from the sibling parts list. Reject any unit that fails two or more parameters.
X-Ray and Destructive Decap for High-Value Applications
For high-reliability applications (e.g., industrial safety interlocks or telecom line cards), add X-Ray inspection and decap verification. A genuine 2-1721142-6 relay exhibits uniform internal architecture: a single-piece copper-alloy contact set, a bobbin-wound coil with even turns, and no voiding in the encapsulation. Counterfeit units often show irregular coil winding, solder bridging, or missing arc-suppression components.
Use X-Ray at a resolution of at least 10 μm. Focus on the contact gap: genuine relays maintain a 0.3–0.5 mm gap in the normally-open position. If the gap is asymmetric or less than 0.2 mm, the unit is likely refurbished (contacts filed down) or defective. Decap a sample from each lot (one per 1000 units) by removing the plastic cap with a Dremel tool under fume extraction. Inspect the armature spring for consistent color (usually zinc-plated steel) and the coil for a varnish coating. Refurbished units often show burn marks or replaced springs with mismatched gauge.
Packaging Audit and COA Cross-Check
Genuine TE Connectivity Potter & Brumfield Relays ship in ESD-shielded tubes or tape-and-reel with a clear, two-layer label. The label includes the part number (2-1721142-6), lot code, quantity (typically 25 or 50), and a 2D Data Matrix code. Scan the Data Matrix and verify it decodes to the same part number and lot code as the printed text. If the label is a single-layer sticker that lifts easily, reject the unit.
Request a Certificate of Analysis (COA) from the supplier. The COA must include the measured coil resistance and pick-up voltage from a sample of that specific lot. Compare these values against your own measurements from the incoming inspection. A mismatch of more than 5% indicates either the COA belongs to a different lot or the supplier is providing generic documentation. Do not accept units if the COA date is older than the production week on the part.
AQL Sampling Plan with Accept/Reject Criteria
Use a standard ANSI/ASQ Z1.4 (or equivalent ISO 2859) normal inspection level II sampling plan. For a lot size of 500 units, sample size is 50. Set the Acceptable Quality Level (AQL) at 0.65% for critical defects (wrong part marking, non-functional relay) and 1.0% for major defects (deviations in pick-up voltage or contact resistance). For example:
- If the lot contains 501–1,200 units, sample 80. Accept on 1 defect, reject on 2.
- If the lot contains 121–500 units, sample 50. Accept on 1 defect, reject on 2.
- Reject the entire lot if any unit fails the X-Ray or decap test.
Document every measurement and attach a pass/fail summary to the procurement record. Rejected lots should be quarantined and returned with a technical non-conformance report referencing the specific parameter that exceeded the acceptance threshold.
Frequently Asked Questions About 2-1721142-6
Frequently Asked Questions About 2-1721142-6
What is the 2-1721142-6 cross-reference part number?
The 2-1721142-6 is also listed as PCJ-112D3MH 301Y. Engineers cross-referencing this part should compare it against sibling numbers 1-1721142-9, 1423685-1, and 1393186-9, which share the same PCJ-series package.
How can I verify the authenticity of a 2-1721142-6 relay without a datasheet?
Perform a coil resistance measurement using a four-wire ohm meter. Compare the reading to typical PCJ-family values (e.g., 360 Ω for 12 VDC coils). Also laser-etch markings must be permanent. Use X-Ray to confirm uniform internal geometry.
Does the 2-1721142-6 comply with RoHS standards?
TE Connectivity Potter & Brumfield Relays generally designs the PCJ series to be RoHS compliant, but engineers must verify the specific lot code against the manufacturer’s latest compliance declaration and the 2-1721142-6 datasheet.
Where can I find the pinout diagram for 2-1721142-6?
The standard PCJ-112D3MH pinout follows a 1-Form-A (SPST-NO) layout with coil pins on one side and load pins on the opposite side. Exact dimensions are in the TE Connectivity Potter & Brumfield Relays drawing for the PCJ-112 package. Always confirm via the official datasheet.
Procurement workflow summary: receive the lot, perform visual marking inspection and YYWW decoding on 100% of units, sample according to AQL level II for electrical tests, and escalate to X-Ray for any lot with visible mark anomalies. Reject immediately if the Data Matrix scan fails or if pick-up voltage deviates more than 10% from sibling part benchmarks. This structured approach minimizes the risk of field failures and protects your BOM integrity.
