A battery-cable lug can have an acceptable crimp height, clean cross-section and low initial resistance yet still be an incomplete durability decision. Temperature changes can move copper strands and terminal material at different rates. Cable mass and machine vibration can bend the conductor at the barrel exit. A support positioned too far from the lug can multiply that motion. Plating, oxide films, strand damage or barrel relaxation can then change the contact network that carried current in the first inspection.
The purchasing question is therefore not simply, “Did the new crimp pass?” It is: Does the exact cable-terminal-tooling-support combination retain its electrical and mechanical evidence after a defined environmental sequence that represents the intended application?
This guide focuses on crimp-joint durability after the initial crimp process has been established. It complements the cable-lug crimp tooling and pull-test guide, the crimp cross-section analysis guide and the battery-cable Kelvin resistance guide. Those guides address process setup, geometry and measurement fundamentals. This article asks how to preserve and recheck those properties after thermal and mechanical exposure.
Nothing here establishes a universal cycle count, vibration spectrum, resistance limit or pull-force limit. It does not verify a SINAWATTS cable, terminal, tooling system, material, test capability, certification, production process, stock level, price, MOQ or lead time. The terminal and cable manufacturers, applicable product standard, equipment designer, qualified laboratory and project approval authority must define the controlling requirements for the exact application.
Direct answer: what should the RFQ require?
For each proposed battery-cable crimp joint, require a controlled durability plan that states:
- cable manufacturer, article, conductor material, strand construction, cross-sectional area, insulation and finished outside diameter;
- terminal manufacturer, order code, barrel geometry, plating, palm geometry and drawing revision;
- approved applicator, die, press, locator, wear parts, setup, crimp-height window and inspection method;
- stripping equipment and settings, strip length, conductor preparation and prohibited practices;
- cable exit direction, bend radius, first-support position, unsupported mass and installed orientation;
- actual service current profile, joint temperature boundary, ambient range, dwell, ramp and powered or unpowered test state;
- vibration axes, spectrum or sweep, acceleration, duration, fixture, cable restraint and electrical monitoring method;
- specimen quantity, build lots, worst-case constructions, controls and destructive witness allocation;
- baseline visual, dimensional, pull, cross-section and four-wire resistance results as applicable;
- the order of thermal, humidity, vibration and electrical exposures;
- intermediate measurements that do not disturb the interface;
- post-exposure visual, resistance or voltage-drop, pull and cross-section checks;
- acceptance limits, measurement uncertainty, failure definition and retest rules;
- raw-data, photograph, calibration and sample-traceability deliverables; and
- change triggers for cable, terminal, plating, tooling, setup, support, route or test method.
Require results for the exact proposed construction. A certificate for a terminal family, a photograph of one cross-section or a statement that a “vibration test passed” does not establish the cable size, fixture, spectrum, sequence, measurement boundary or acceptance limit.
Keep initial process approval and durability approval separate
Initial crimp approval asks whether a controlled tool forms the specified cable and terminal correctly. It normally considers wire preparation, crimp dimensions, visual condition, pull performance, cross-section and electrical measurements. Durability approval asks whether that accepted construction remains stable after defined stress.
The two decisions must connect but should not be collapsed. A poor starting crimp should not enter environmental testing merely to see whether it survives. Conversely, a beautiful initial cross-section does not prove long-term performance under cable movement. Use an initial gate before the durability sequence, then compare the same non-destructive measurements before and after exposure. Allocate separate destructive specimens for pull and cross-section because those examinations consume or alter the sample.
The process release should also define routine production controls. Environmental qualification is usually performed on a bounded sample set; it does not replace crimp-height checks, tooling maintenance, conductor inspection or first-article records on production lots. Qualification shows what one controlled design can withstand. Production evidence shows that current assemblies still represent that design.
Understand the failure mechanisms before choosing a test
Crimp durability is influenced by more than nominal cable size. Thermal expansion and contraction can redistribute force among strands, barrel wings and conductor interfaces. A large temperature difference across a short joint can add local strain. Current heating can create a different gradient from a chamber that heats the complete specimen uniformly. The insulation support crimp or heat-shrink transition may constrain movement and move the bending point to the conductor exit.
Vibration can impose axial, lateral, torsional or combined motion. The joint may experience little stress when the cable is clamped close to the barrel, but much more when a heavy unsupported length acts as a lever. Resonance of the cable-fixture system can amplify movement at a narrow frequency. A test report that omits fixture geometry and support distances cannot be transferred confidently to a different harness layout.
Potential observations include increased resistance, intermittent discontinuity, broken outer strands, conductor pullback, barrel cracking, insulation-support damage, plating wear, fretting debris, loosened terminal hardware or heat damage. No single observation tells the entire story. A stable millivolt reading does not prove that no strands have broken; a high pull force does not prove low electrical resistance; and one polished cross-section cannot show the behavior of every sample.
Use published sources within their stated boundaries
The current IEC product page for IEC 60352-2:2024, checked on 2026-10-02, describes requirements, test methods and practical guidance for solderless crimped connections using specified crimp barrels. Its public scope covers stranded wires from 0.05 mm² through 10 mm² and says the document addresses electrical stability under prescribed environmental conditions. That scope is useful for smaller crimped connections, but many battery cables exceed 10 mm². Do not cite IEC 60352-2 as direct approval for a larger joint unless the governing specification and qualified authority establish how it applies.
An official USCAR change letter for SAE/USCAR-21 Revision 4, Letter 6, checked on 2026-10-02, illustrates an automotive crimp environmental sequence. The published graphic identifies visual inspection and dry-circuit resistance for wire sizes at or below 6 mm², or voltage drop for larger wires, around thermal-shock and temperature-humidity exposures. It shows 72 thermal-shock cycles between stated hot and cold dwells. Those numbers belong to that revision and automotive specification; they are an evidence example, not a universal battery-cable recipe. A buyer should use the applicable purchased specification and project requirements rather than copying the graphic into an unrelated marine, stationary-storage or industrial RFQ.
TE Connectivity’s official paper “Crimping Terminals: The Importance of Using the Right Tool”, checked on 2026-10-02, explains that terminal and tooling are engineered together. It warns that an overly tight crimp can damage the terminal or strands and reduce tensile strength or vibration resistance, while a loose crimp can degrade mechanical and electrical performance. The paper describes general crimp principles and examples; it does not establish acceptance values for an unrelated terminal.
Together, these sources support three procurement rules: specify the exact construction, preserve the test sequence and measurement boundary, and avoid treating “more compression” as automatically better.
Freeze the test object before discussing cycle counts
A durability report is only transferable when the tested object matches the offered object. Build a specimen definition with the following fields:
On small screens, swipe or scroll sideways to read every column. Keyboard users can focus the table and use the arrow keys.
| Interface field | What to record | Why it matters |
|---|---|---|
| Conductor | Material, plating, strand count/class, nominal area and supplier article | Changes deformation, stiffness and current path |
| Insulation | Material, wall, OD and strip method | Affects support, heat transfer and exit strain |
| Terminal | Exact part, material, plating, barrel and revision | Defines geometry and interface materials |
| Tooling | Press, applicator/die, locator, setup and maintenance state | Creates the crimp profile |
| Crimp | Height, width where controlled, orientation and visual result | Confirms the starting process window |
| Protection | Heat shrink, boot, sealant and recovery process | Changes stiffness, moisture and thermal boundary |
| Route | Bend radius, exit angle, support spacing and free mass | Establishes mechanical loading |
| Hardware | Stud, washer stack, torque and anti-rotation controls | Separates crimp behavior from bolted-joint behavior |
If the purpose is to qualify the crimp itself, design the fixture so the bolted palm interface does not dominate the measurement. If the purpose is to qualify the complete cable assembly, include the real palm joint, supports and protective materials and label the result accordingly. Do not report a complete assembly voltage drop as “crimp resistance” unless the method isolates that boundary.
Translate the service profile into bounded exposures
Start with equipment inputs rather than a familiar laboratory recipe. Record minimum and maximum cable-compartment temperature, current duty, energized duration, start events, cooling time, vibration sources, installation orientation, cable support, shock events, humidity, fluids and expected maintenance. Separate normal operation from storage, transport, fault and service conditions.
Then map each risk to a test or inspection. Chamber thermal cycling can reveal expansion-related changes. Current cycling can reproduce self-heating and a joint-to-cable temperature gradient. Vibration can exercise the support and barrel exit. Humidity or corrosive exposure may be relevant where sealing is incomplete. Combining every stress at its maximum can produce an unrealistic test, while testing each stress on unrelated samples can miss interactions. The responsible engineer should choose the sequence and justify it.
Write the profile with numbers and tolerances only after obtaining the application and standard requirements. Include ramp rate, dwell definition, sample stabilization, number of cycles and whether measurements occur hot, cold or after recovery. “Thermal cycle from cold to hot” is not reproducible.
Build a specimen matrix that can answer the question
One assembly cannot provide every required result. Pull testing destroys the joint. Cross-sectioning removes the inspected location. Frequent disconnection for measurement can change a lug stack. Divide samples into groups while keeping traceability to the same material and process lots.
A practical matrix can include:
- Group A, electrical trend: untouched assemblies measured at baseline, defined intermediate points and final condition;
- Group B, mechanical retention: baseline specimens and separately aged specimens pulled with the same fixture and rate;
- Group C, metallography: baseline and aged witness crimps sectioned at defined locations using the same preparation method;
- Group D, installation assembly: complete routed cables used to verify support, bending, fastener and vibration interactions; and
- Group E, controls: unexposed references stored in a controlled condition to reveal measurement drift or storage effects.
Distribute cable, terminal and production lots across groups. Do not put all worst-looking samples into one group or select only visually ideal samples for durability. State sample-selection rules before testing. Record any specimen lost to fixture error separately from a true product failure, and allow reclassification only through a documented technical review.
Establish a trustworthy electrical baseline
Use a four-wire Kelvin method or another approved low-resistance method with defined current, polarity, stabilization time, contact points, temperature and instrument range. Mark the voltage-sense locations so the post-test measurement covers the same conductor and terminal length. A few millimetres of changed probe position can matter when the joint resistance is very small.
Record ambient and specimen temperature. Copper resistance varies with temperature, so comparing a warm post-vibration sample with a cool baseline can create a false trend. Either measure at a controlled reference condition or use an approved correction method with clearly stated assumptions. Preserve raw voltage and current readings, not only a rounded calculated value.
Use statistics that show individual samples. An average can hide one deteriorating joint. Report baseline value, final value, absolute change, percentage change where meaningful, measurement uncertainty and acceptance status for every specimen. Define how readings near the instrument resolution will be handled. Never invent a universal micro-ohm limit; derive the limit from the validated design, governing specification and measurement capability.
Design thermal cycling around the actual thermal boundary
Thermal cycling should state where temperature is measured. Chamber air, terminal palm, barrel, conductor and insulation can lag one another. Dwell begins either when chamber setpoint is reached or when the specimen reaches a defined condition; those choices produce different exposure. Specify which applies.
For a powered cycle, define current waveform, source control, connection losses outside the specimen, temperature sensors and over-temperature protection. Current can heat the crimp and conductor non-uniformly, which may better represent service but complicates measurement. For an unpowered chamber cycle, explain what service mechanism the uniform temperature change represents.
Avoid using the maximum cable temperature rating as the automatic chamber setpoint. That marking may relate to material capability under a specified standard, not the equipment’s actual continuous joint temperature. Obtain terminal, cable and equipment limits and choose the controlling boundary. Include protective boots and heat shrink when they are part of production because they change heat dissipation and stiffness.
After cycling, allow a defined recovery condition before comparison unless the standard requires hot or cold measurement. Inspect for insulation movement, seal damage, strand exposure, plating change and barrel cracks before disturbing the sample.
Make the vibration fixture part of the qualification record
Vibration evidence is inseparable from the fixture. Draw the terminal restraint, cable exit angle, first clamp, unsupported length, free mass, bend and axis. Photograph the built setup with a scale and sample ID. State whether the terminal palm is bolted, clamped or otherwise restrained and how that restraint avoids introducing an unrealistic stress concentration.
Run the required axes and spectrum or sweep from the governing application. Record control and response accelerometer locations, not just shaker input. If a cable resonance produces a large local response, document it rather than smoothing it out without engineering approval. Monitor fixture loosening so a fixture failure is not mistaken for terminal durability.
Where the project requires continuity monitoring, define the detection threshold and minimum interruption duration. A final resistance measurement can miss a transient open circuit that occurred during vibration. Conversely, an unshielded monitoring circuit can report electrical noise as discontinuity. Validate the acquisition setup before qualification.
The complete cable route matters. The cable-assembly strain-relief guide explains how support and bend geometry control loading. A qualification performed with a clamp 20 mm from the barrel should not be claimed for an installation with a long unsupported cable unless equivalence is demonstrated.
Use a planned sequence and control sample handling
Test order can expose or conceal interactions. Thermal cycling before vibration may relax or embrittle an interface that vibration then exercises. Vibration first may create strand or plating damage that later thermal movement expands. A governing standard may prescribe the sequence; follow it exactly when claiming compliance.
Create a sequence sheet with hold points. At each hold point, list permitted inspections, measurement conditions and maximum time before the next exposure. Do not straighten a cable, re-torque a stud, push insulation back into place or clean debris unless the procedure calls for it. Such actions can erase evidence.
If several methods require unplugging measurement leads or removing a terminal from the fixture, analyze whether handling changes the joint. Prefer permanent Kelvin sense leads outside the evaluated crimp boundary where the method permits. Record every intervention.
Recheck electrical performance without changing the boundary
Post-test resistance must use the same measurement definition as baseline. Verify instrument calibration status, lead arrangement, current direction, stabilization and sample temperature. Repeat readings to assess connection repeatability, but do not average away an unstable interface.
For long battery cables, total assembly resistance can be dominated by conductor length. Use fixed datums and, when the approved method requires it, compensate or separately characterize conductor contribution. Keep the original raw assembly value visible. A calculated crimp-only number built from uncertain subtractions can be less reliable than a well-bounded complete-assembly comparison.
Review trend shape as well as the final point. A step change after a specific vibration axis suggests a different mechanism from a gradual change across current cycles. Align electrical data with chamber, current and shaker timestamps. Preserve the trace so the approval authority can investigate anomalies.
Use pull tests as comparative destructive evidence
Pull force measures one mechanical failure mode under a defined fixture and rate. It does not reproduce every installed vibration load, and it does not prove electrical stability. Use separate baseline and exposed specimens built from the same controlled process. Record whether insulation support is disabled or included, how the terminal is gripped, the pull direction and speed, peak force and failure mode.
Failure location matters. Conductor break outside the barrel, strand pullout, barrel opening and terminal fracture are not equivalent observations. Compare the aged distribution with baseline and with the applicable minimum. Avoid claiming improvement from a higher average if scatter widened or the failure mode became undesirable.
Do not pull a specimen that must later be sectioned as an undisturbed aged crimp. The pull has already deformed it. Allocate independent witnesses.
Use cross-sections to explain, not to replace, performance
Cross-section analysis can reveal strand distribution, barrel closure, wings, cracks, gross voids and compression geometry at the cut plane. It cannot by itself prove resistance stability along the full barrel or detect every broken strand. State the cut location, mounting, grinding, polishing, etching, imaging and measurement method.
Compare baseline and aged sections from traceable builds. Look for changes that align with electrical or mechanical trends, but avoid diagnosing a mechanism from one plane alone. If vibration damage is expected at the barrel exit, add external microscopy or another approved inspection there rather than assuming a mid-barrel cut will find it.
The crimp cross-section analysis guide provides a fuller RFQ framework for metallographic evidence.
Worked example: compare two test plans without inventing a pass limit
Assume a project uses the same nominal 35 mm² copper cable and lug in two layouts. Layout A supports the cable 40 mm from the barrel and has little free mass. Layout B supports it 180 mm away after a bend. The buyer receives two supplier proposals:
On small screens, swipe or scroll sideways to read every column. Keyboard users can focus the table and use the arrow keys.
| Plan | Thermal evidence | Vibration evidence | Electrical evidence | Decision quality |
|---|---|---|---|---|
| Supplier 1 | 100 chamber cycles, profile shown | “Passed vibration,” no fixture drawing | Final continuity only | Weak: cycle count exists, but route load and resistance trend are unknown |
| Supplier 2 | Fewer cycles tied to a named application requirement | Three-axis setup with Layout B support geometry | Fixed-datum baseline/intermediate/final Kelvin data | Stronger: boundaries and worst-case route are reviewable |
The example does not say fewer cycles are always sufficient or that 35 mm² requires a particular method. It shows why a large cycle count cannot compensate for an unrepresentative fixture or insensitive measurement. The responsible engineer must still decide whether the actual profile, duration, sample size and limits are adequate.
A simple screening calculation can help identify the worst fixture. If the unsupported cable section has an effective moving mass of 0.20 kg and experiences a fixture response of 8 g at a resonance, the inertial force estimate is:
F = m × a = 0.20 kg × 8 × 9.81 m/s² ≈ 15.7 N
If the force acts with an effective 0.15 m lever arm from the barrel exit, the nominal bending moment estimate is about:
M = F × L = 15.7 N × 0.15 m ≈ 2.36 N·m
This is a fictional screening example, not a terminal allowance and not a complete dynamic model. Cable flexibility, clamp motion, damping, direction and resonance shape change the actual load. Use it to compare fixture concepts and request engineering evidence, not to approve a lug.
Define acceptance before the laboratory starts
The plan should specify:
- no prohibited visual damage or transient discontinuity;
- maximum resistance or voltage-drop change using the approved boundary;
- pull-force minimum and acceptable failure modes;
- cross-section criteria where required;
- sample-level versus group-level acceptance;
- treatment of measurement uncertainty;
- fixture-failure and equipment-fault rules;
- retest conditions and maximum retest count; and
- technical-review authority for anomalies.
Do not create limits after seeing the data. Avoid “no significant change” unless “significant” is numerically defined. A percentage limit can mislead when baseline values approach instrument resolution; an absolute limit can mislead across different joint sizes. Select the metric during method validation.
A failure should trigger root-cause work linked to sample identity, not an automatic replacement of the worst point. Rebuilding only failed samples with unrecorded tooling adjustments destroys comparability. Document corrective action and repeat the affected qualification scope with an approved plan.
Connect qualification to production process evidence
The durability report should trace each sample to terminal and cable lots, press and applicator, die and locator IDs, crimp-height measurements, strip setup, operator or automated cell, date and any process-monitoring record. This allows the approved process window to be transferred into production documents.
Routine controls may include crimp height, visual criteria, conductor brush, strip length, pull samples, cross-section frequency, press-force monitoring and tool-maintenance intervals. The correct set and frequency depend on risk and validated process capability. Environmental cycling is not normally repeated on every lot, but changes and excursions may require targeted requalification.
The battery-cable first-article and change-control guide explains how to connect the approved sample to released drawings and records.
Treat changes as possible requalification triggers
Require prior notice for changes to:
- conductor supplier, material, plating, strand count or class;
- insulation material, wall, OD or stripping method;
- terminal supplier, material, plating, barrel or manufacturing location;
- applicator, die, press, locator, crimp height or wear-part policy;
- heat shrink, boot, sealant or recovery process;
- palm hardware, torque, washer stack or anti-rotation method;
- cable exit, bend radius, support distance or installed orientation;
- current profile, temperature boundary or vibration environment;
- test fixture, laboratory, instrument or analysis method; and
- acceptance criteria or data-processing rules.
Not every change requires the complete original test, but “same nominal size” is not an equivalence argument. A cross-functional approval should identify affected mechanisms and the evidence needed. Preserve the prior and new results with an explicit disposition.
Compare supplier returns with an evidence matrix
On small screens, swipe or scroll sideways to read every column. Keyboard users can focus the table and use the arrow keys.
| RFQ field | Evidence to request | Release condition | Hold point |
|---|---|---|---|
| Construction | Exact cable, terminal, plating and revisions | Offered BOM matches tested BOM | Family-level brochure only |
| Process | Tooling IDs, setup, dimensions and traceability | Samples came from controlled production process | Hand sample with unknown setup |
| Route | Exit, bend, support and moving mass | Fixture represents approved worst case | Cable clamped unrealistically close |
| Thermal profile | Limits, ramps, dwells, cycles and sensor position | Profile maps to requirement | Cycle count without temperature history |
| Vibration | Axes, spectrum, duration, control and response | Complete trace and fixture drawing supplied | “Passed vibration” statement |
| Electrical | Fixed datums, method, raw baseline and final data | Individual trends meet pre-set limits | Continuity only |
| Mechanical | Baseline/aged pull data and failure modes | Distribution and modes accepted | Peak value without method |
| Section | Defined preparation and cut location | Traceable baseline/aged images accepted | One marketing micrograph |
| Anomalies | Failure log, fixture events and disposition | Every event has approved disposition | Failed points omitted |
| Production | Routine controls and maintenance | Released plan represents qualified build | Qualification disconnected from production |
| Change control | Notice list and requalification logic | Affected evidence reviewed before supply | Silent substitution allowed |
Compare total evidence cost rather than test price
The lowest laboratory quotation may omit fixtures, instrumentation, witness samples, raw data or engineering review. Normalize bids by specimen count, test sequence, powered-current equipment, sensor channels, continuity monitoring, resistance method, destructive checks, reporting and failure investigation.
Also consider the cost of an unrepeatable result. If fixture drawings and raw data are missing, a buyer may need to repeat the entire program after a route change. A more complete report can reduce later investigation time, but only when its scope matches the offered product.
Request current price, sample charges, tooling charges, MOQ and lead time directly from each bidder for the exact scope. This guide supplies no commercial value or availability claim.
Build the approval in a controlled sequence
1. Freeze the interface and application
Release the cable, terminal, crimp process, protection, bolted interface, cable route, support and environmental inputs. List unresolved items as hold points.
2. Approve the initial crimp process
Verify stripping, tooling, dimensions, visual criteria, electrical baseline, pull and cross-section using the appropriate specimen groups. Do not start durability exposure with a nonconforming process.
3. Approve the durability plan
Map each exposure to the service risk or governing requirement. Approve sequence, samples, fixtures, measurement datums, acceptance and retest rules before testing.
4. Run and preserve the evidence
Record chamber and shaker traces, electrical data, continuity events, sample handling, photographs and calibration status. Quarantine anomalies for technical review.
5. Transfer the result into production and change control
Link the tested BOM and process window to released drawings, routine inspection and notification triggers. Reassess evidence when a change affects the qualified boundary.
Send a complete battery-cable crimp durability RFQ
Provide the circuit duty, current profile, cable and terminal BOM, crimp drawing, equipment temperature range, route and support drawing, vibration inputs, protective materials, applicable standards, sample expectations and approval authority.
Ask each bidder to return the completed evidence matrix, exact construction documents, initial crimp records, proposed environmental sequence, fixture drawings, instrument and datum plan, individual raw results, photographs, failure dispositions, production-control plan and change-notification list. Request current price, sample terms, tooling charges, MOQ and lead time as written project-specific responses.
Send a battery-cable crimp durability RFQ
Buyer FAQ
Does a good crimp cross-section prove vibration durability?
No. A cross-section describes geometry at one cut plane. Vibration behavior also depends on cable mass, support distance, exit angle, strand condition, terminal design and fixture response. Combine section evidence with bounded electrical and mechanical testing.
Can continuity testing replace Kelvin resistance measurements?
No. Continuity can detect an open circuit at its threshold but may not resolve a small degradation in a low-resistance joint. Use the approved resistance or voltage-drop method and add live discontinuity monitoring when the vibration requirement calls for it.
Should resistance be measured immediately after a hot cycle?
Only if the governing method says so. Temperature strongly affects conductor resistance. Define measurement temperature, recovery and correction before testing so baseline and final readings are comparable.
Is the USCAR thermal-shock profile suitable for every battery cable?
No. The cited graphic belongs to SAE/USCAR-21 Revision 4 and its automotive scope. Use the controlling specification and actual application. Do not copy its temperatures or cycle count into an unrelated project without engineering justification.
Does IEC 60352-2 cover a 35 mm² battery cable crimp?
The public IEC page states a stranded-wire scope through 10 mm². A 35 mm² construction is outside that published range. Use an applicable large-cable, product or industry requirement and obtain approval from the responsible authority.
Can we use the same specimens for pull tests and cross-sections?
Not as undisturbed evidence. Pull testing deforms or destroys the joint. Allocate separate traceable samples for aged pull testing and aged cross-section analysis.
What is the most important vibration-fixture dimension?
There is no single universal dimension. Cable exit, first support, unsupported length, moving mass, bend, orientation and terminal restraint work together. Preserve the complete fixture drawing and response measurement.
Is a lower crimp height always better for vibration resistance?
No. The TE source explains that too much compression can damage strands or the terminal and reduce tensile or vibration performance. Use the terminal-tooling manufacturer’s validated process window.
Should thermal cycling and vibration use separate samples?
The governing test plan decides. Separate groups isolate mechanisms; a combined sequence can expose interactions. If both are used, preserve unexposed controls and enough destructive witnesses to interpret the result.
What if one specimen shows a resistance step but still meets the final limit?
Investigate it. Correlate the step with the exposure timestamp, repeatability, fixture events and physical inspection. A pre-set acceptance rule controls pass/fail, but an unexplained step may still indicate a process or method issue requiring disposition.
When should a process change trigger requalification?
When it can affect the electrical, mechanical, thermal or environmental boundary and equivalence is not demonstrated. Examples include conductor construction, terminal plating, tooling, crimp height, support geometry and test method changes.
Does this guide verify SINAWATTS battery-cable durability?
No. It is an RFQ and evidence framework. Obtain current written evidence for the exact offered construction and application from the responsible suppliers and approval authority.