Custom Waterproof Cable Harness RFQ: Length, Branches, Tests

Scope and boundaries

Applies to RFQs for custom waterproof cable harnesses built on circular waterproof connector series where cable length, branch breakouts and exit interfaces must be defined. Prices, minimum order quantities, lead times and project-specific test values are not set here; they are confirmed per configuration against the applicable drawings, specification sheets and reports.

What the quote cannot cover yet

A custom waterproof cable harness RFQ often goes out with a series name, a pin count and an approximate length — and comes back as prices that describe different products. An RFQ that names only a series and a wire gauge will return quotes for different products; comparable pricing starts only when the mating part, pinout, conductor size, cable outer diameter, branch geometry, and acceptance documents are fixed in writing.

The items most often missing are the mating half's part number, the wiring definition, the jacket outer diameter, the branch positions and the verification scope. If any branch position, cable outer diameter, or acceptance document is still open, mark the RFQ as budgetary and request engineering review instead of asking for a firm price; if these items are fixed, ask each supplier to quote against the same drawing and state which items their price excludes.

Sources: LLT selection guide

Interface task: name the mating half, not just the series

Series names such as M8, M12 or M16 describe a size family, not a mating guarantee. A pair mates only when the interface dimensions, thread or locking structure, coding, pin count, pin assignment and mating model all agree — checked against both sides' drawings, not a mirrored image. Communication links add shielding and transmission requirements to the list.

Mounting style and contact form are separate choices: front-mount, rear-mount, flange and in-line describe structure, while pin or socket describes the contacts. Panel cutout, board thickness and locking follow the specific part number's drawing, and face views should state the viewing direction and keying datum before anyone quotes tooling or wiring.

Sources: LLT selection guide · Technical applicability

Load and cable data belong on separate lines

State working voltage and current per contact or contact group, with each core's duty. In hybrid layouts such as a 3+2 arrangement, the two contact groups are checked separately and their current ratings cannot be added into one machine rating; simultaneous loading, conductor size, ambient temperature and heat dissipation all move the temperature rise, so catalog values are a first screen and the final check follows the specification sheet.

Keep conductor size and cable diameter on separate lines of the RFQ. A cable's conductor cross-section and its jacket outer diameter are separate specifications: the cross-section is stated in mm² per core, AWG numbers follow the catalog's correspondence, and the outer diameter in millimeters must fall inside the sealing range of the chosen configuration. Cables with the same conductor area can differ in outer diameter through core count, insulation or jacket, so conductor size alone never validates the seal.

Sources: Technical applicability · LLT selection guide

Harness geometry: length, branches and exit direction

State the cable length and its tolerance, each branch position, the exit direction at every leg, and the tail-end treatment — stripped, terminated or left for field wiring. A branch is not a sketch note; it is an additional exit interface whose sealing, clamping and strain relief must be defined before it can be priced.

Termination belongs in the same decision: field assembly lets length follow the actual routing, while an overmolded harness finishes length, wiring and end structure before delivery. The choice depends on routing space, maintenance method and batch assembly flow, and on whether the chosen model supports that termination; an existing sample or drawing can start the engineering evaluation.

Sources: LLT selection guide

Environment and verification conditions

IP67 denotes dust-tightness and short-term immersion protection under defined test conditions, and it depends on the connector being correctly mated and locked, with intact seals and a cable of the specified outer diameter. Unmated ports, the far cable end and device openings need their own protection, and IP6X dust protection does not qualify a connector for explosive dust atmospheres. Long-term immersion and high-pressure washdown are different test conditions: give water depth, duration, temperature, medium and cleaning method, and choose a configuration with matching verification data.

Weathering figures need the same discipline. Supplier-declared figures such as UV resistance of 1,000 hours or more and salt fog of 480 hours or more describe performance under specific test conditions and cannot be converted directly into years of outdoor service. They apply to the tested material, coating and sample state, with appearance and electrical criteria judged separately; request the records that match your configuration.

Sources: Technical applicability · IEC 60529 — Degrees of protection provided by enclosures

Acceptance documents and certification scope

Acceptance documents define what passed means at goods-in. UL 94 V-0 is a flammability classification for a plastic material, tied to grade, thickness and color; a material yellow card does not certify the finished connector. Coverage under UL 2238, UL 1977, TÜV or SAA follows the models, ratings and structural versions named on each certificate; CE follows the applicable regulations and declaration of conformity.

Name the target model, application and sales market, and request documents per SKU. Also record what will be inspected on receipt — wiring against the pinout, seal seating, clamping and assembly state — with torque and strip dimensions taken from the model's documentation, not assumed.

Sources: Technical applicability · LLT selection guide

Quantity, delivery scope and open commercial items

Commercial terms become comparable only after the configuration is fixed. State sample and production quantities, the delivery scope — harness alone or with mating halves and cable — and who owns sample validation, since custom designs require corresponding sample verification.

The published material confirms what information a harness RFQ should contain and which conditions ratings such as IP67 depend on; it does not provide prices, minimum order quantities, lead times, or project-specific test reports, so those items must be confirmed per configuration with the manufacturer. Leaving them open does not speed up a quote; it turns the quote into an estimate.

Sources: Technical applicability · LLT selection guide

RFQ submission checklist

With these items fixed, a manufacturer can quote a defined configuration instead of an assumption, and goods-in can check the delivery against the same list. Send the interface drawing, load data, cable specification, installation environment, quantities and required documents, and ask for any open items to be named in the reply.

• Interface drawing or mating model, with pin count and wiring definition
• Working voltage and current per contact or contact group
• Cable length and tolerance, branch positions and exit direction at each leg
• Conductor cross-section in mm² per core, with AWG where used, and jacket outer diameter in mm, plus cable material
• Tail-end treatment and termination method: field assembly or overmolded
• Environment and verification: rain, immersion, washdown, UV, salt fog, temperature, and the evidence expected for each
• Quantity, delivery scope, and required certificates or declarations; an existing sample or drawing can start the evaluation

Sources: LLT selection guide

Frequently asked questions