A useful RFQ lets suppliers quote the same technical requirement. “Step-down butt connector for 18 and 14 AWG” is not enough because strand construction, insulation diameter, barrel material, sealing, tooling, tests, packaging, and volume can change the design and price.
Use this template as a starting point and attach the actual wire datasheets.
Treat the RFQ as a controlled technical package shared by engineering, quality, procurement, and each bidder. It should separate mandatory requirements, preferences, and areas where a supplier may propose an alternative. Otherwise, quotations that look comparable may be based on different materials, tools, tests, or packaging assumptions.
Control the RFQ Documents
Assign an RFQ number, revision, issue date, owner, response deadline, and question deadline. List every attachment and revision, including wire datasheets, drawings, application specifications, validation plans, packaging artwork, forecasts, and quality agreements. State which document takes precedence if requirements conflict.
Require a line-by-line response using Comply, Comply with clarification, Alternative proposed, or Cannot comply. Every clarification and alternative should reference a numbered supplier note explaining technical, cost, tooling, validation, MOQ, and schedule effects. Verbal discussions should be incorporated into a revised RFQ or formal clarification before award.
1. Application Information
- End product and circuit function
- Indoor, cabin, engine-bay, outdoor, marine, or industrial location
- Nominal and maximum current and voltage
- Operating temperature and environmental exposure
- Vibration, flexing, fluid, humidity, or corrosion requirements
- Applicable customer, industry, and regulatory specifications
Do not ask the supplier to infer a safety classification from the product name.
Describe circuit function and consequence of failure. Identify power, signal, grounding, control, service repair, or another use; installation location; duty cycle; expected service life; adjacent materials; and assembly method. State relevant exposure to heat, cold, vibration, flexing, abrasion, moisture, salt, chemicals, oils, or cleaning agents. Avoid copying every possible environmental test into the RFQ without connecting it to the real application.
For electrical inputs, provide normal and maximum current, system voltage, transient conditions, and any defined voltage-drop or resistance requirement. Cite the drawing, customer specification, or qualification plan controlling each value. The connector supplier should not be expected to determine end-product derating or regulatory classification without system-level information.
2. Large- and Small-Side Wire Data
For each side provide AWG or mm2, conductor material, plating, strand count, insulation material, insulation diameter, and required strip length. State whether either end contains multiple wires.
TONFUL’s wire AWG and insulation selection guide helps separate conductor and jacket data. The dissimilar wire size guide explains the basic transition.
Nominal gauge is only one input. Two wires with the same AWG or mm² can have different strand counts, individual strand diameters, compaction, conductor plating, and insulation outside diameters. Attach actual manufacturer datasheets and provide samples for compact conductors, fine strands, unusual insulation, or multiple-wire insertions.
| Wire input | Large side | Small side | Supplier confirmation |
|---|---|---|---|
| Manufacturer and wire part number | Buyer entry | Buyer entry | Exact or approved equivalent |
| Conductor area and tolerance | Buyer entry | Buyer entry | Supported range |
| Material, plating, strand construction | Buyer entry | Buyer entry | Compatibility reviewed |
| Insulation material and OD tolerance | Buyer entry | Buyer entry | Entry and sealing reviewed |
| Number of inserted conductors | Buyer entry | Buyer entry | Effective size evaluated |
| Strip-length requirement | Buyer entry | Buyer entry | Process window proposed |
If multiple conductors enter one end, require the supplier to identify the effective-wire-size calculation and governing specification. Do not approve a barrel merely because the conductors can be pushed into it.
3. Connector Construction
Specify or request proposals for:
- Barrel base material and plating
- Large- and small-end conductor ranges
- Barrel seam and center stop
- Insulation material, color, and transparency
- Heat-shrink ratio and adhesive where required
- Overall dimensions and marking
- Required certifications or declarations
Use TONFUL’s step-down butt connector guide to identify architecture options.
Request a controlled drawing showing large- and small-end inside diameters, conductor-barrel lengths, transition geometry, center stop, seam, entry features, insulation support, overall dimensions, and critical tolerances. Define base metal and applicable material specification, plating, insulation resin, adhesive where relevant, color, marking, and restricted-substance documents.
Replace a vague “waterproof” request with the required exposure, installation process, conditioning, test method, acceptance criteria, and approval authority. Specify whether sealing is required around each wire jacket, around the complete splice, or through a separate harness-protection system. Both insulation diameters must fall within the validated sealing window.
4. Tooling and Process
List available hand tools, presses, applicators, dies, and target production volume. Ask the supplier to identify the approved tool and cavity for each end, plus strip length, crimp orientation, nominal crimp height, inspection method, and maintenance requirements.
Separate connector-production tooling from customer crimp tooling. Request tool and die IDs, cavity, locator, setting, orientation, cycle control, maintenance schedule, wear criteria, verification method, spare availability, and ownership. If the two ends use different cavities or operations, require mistake-proofing and a two-end work instruction. A generic die-family name is not evidence that the exact connector and wire pair are qualified.
5. Validation and Documents
Request only the evidence your project needs, such as:
- Dimensional report
- Material declarations
- Both-end crimp-height data
- Both-end pull-force results
- Electrical resistance results
- Cross-section images
- Environmental test report
- Tool drawing and work instruction
- Lot traceability and change-notification plan
Each test request needs a requirement source, method, sample quantity, conditioning, equipment requirement, acceptance limit, report format, and treatment of invalid tests and retests. Require separate results for both ends. One pull result cannot validate the opposite end, and a cross-section image without sample ID, wire, tool, cavity, crimp height, and acceptance criteria is not auditable evidence.
For resistance testing, define test current, four-wire Force/Sense probe locations, reference wire length, ambient temperature, offset compensation or forward/reverse measurement where required, conductor-baseline subtraction, and initial-to-aged change if applicable. Environmental testing should be required only when specified by the qualification plan, product specification, or customer requirement.
The official IPC/WHMA-A-620 release page confirms that the standard addresses methods, tests, and acceptability for cable and harness interconnections. State the required revision and class rather than writing “IPC compliant” without scope.
6. Commercial and Packaging Data
Provide prototype quantity, first order, annual forecast, target price basis, delivery location, incoterm, requested lead time, packaging format, pack quantity, label, barcode, private-label artwork, and sample approval timing.
Ask suppliers to separate engineering, forming tools, application tools, gauges, validation, samples, unit price, packaging, and freight. Include forecast assumptions, order frequency, service demand, currency, Incoterm, payment terms, quote validity, sample timing, production lead time, and capacity expectations. Ask what drives the MOQ: material purchase, plating batch, color batch, setup, printed packaging, or commercial policy.
Packaging requirements should define bag and carton materials, inner and outer quantities, quantity tolerance, sealing, deformation protection, contamination control, label fields, barcode standard, lot/date code, artwork approval, and required languages. State shelf life only when it is technically applicable and supported.
7. Quality Planning and Production Control
Require the selected supplier to link Process Flow → PFMEA → Control Plan → Work Instruction → Inspection Record. Critical drawing and performance characteristics should appear consistently throughout that chain. Request incoming, setup, in-process, final, and release controls with method, frequency, sample size, record fields, responsibility, and reaction plan.
Include first-piece approval after startup, tool change, material change, adjustment, and defined downtime restart. Request MSA or GR&R for critical dimensional measurements, plus SPC and Cp/Cpk or another appropriate capability analysis for stable measurable processes. Acceptance criteria must come from the approved quality agreement rather than an invented generic threshold.
Define traceability for base metal, plating, insulation, adhesive, production lot, equipment, tooling, shift, inspection, packaging, and shipment. Require sub-supplier and outsourced-plating control, calibration traceability, personnel authorization, segregation of nonconforming product, corrective action, mock recall, and notification before specified changes.
Copyable RFQ Specification Template
| Field | Buyer entry |
|---|---|
| Application and location | |
| Large-side wire specification | |
| Small-side wire specification | |
| Electrical and temperature requirements | |
| Connector construction | |
| Environmental protection | |
| Approved or available tooling | |
| Required tests and acceptance documents | |
| Prototype / order / annual quantities | |
| Packaging and labeling | |
| Delivery terms and target date | |
| Change notification requirement |
Supplier Response and Award Matrix
| Evaluation area | Buyer weight | Supplier response | Evidence ID | Action, owner, due date |
|---|---|---|---|---|
| Technical and drawing compliance | ||||
| Wire and tooling compatibility | ||||
| Validation and quality planning | ||||
| Traceability and change control | ||||
| Commercial and capacity fit | ||||
| Packaging and logistics |
Normalize bids before comparing price. Include tooling, validation, packaging, freight, MOQ exposure, deviations, and expected maintenance. Keep technical blockers separate from commercial preferences. An unresolved issue affecting safety, electrical function, material identity, traceability, or required validation should prevent award.
Sample and Pilot Approval
Use staged gates: requirement review, drawing approval, material or color sample where needed, dimensional samples, crimped samples using both wires, qualification testing, packaging approval, and pilot lot. Define who approves each gate and what evidence is required. Submission of a report is not the same as approval.
The pilot should use production-intent materials, tools, operators, methods, and packaging. Trace at least one finished pack backward to incoming lots and forward to shipment records. Confirm that product, labels, revision, quantity, and inspection status agree. Retain approved samples and baseline reports for future lot and change comparisons.
Review Before Sending
Confirm that the RFQ includes actual wire datasheets, separates both ends, identifies test authority, and distinguishes mandatory requirements from supplier proposals. Use TONFUL’s manufacturer red-flag guide when comparing responses.
Before release, engineering should approve application and drawing inputs, quality should approve validation and controls, procurement should approve commercial terms, and the responsible packaging owner should approve artwork and logistics. Resolve contradictions and close all critical questions with named owners and dates.
For supplier nomination, use TONFUL’s step-down butt connector manufacturer audit checklist to confirm that the quoted controls exist at the proposed production location. Record evidence and unresolved findings so unit price cannot conceal validation, traceability, or change-control risk.
Send the completed package to TONFUL for feasibility review, sample planning, and quotation.
