Waterproof Cable Assembly RFQ: What to Specify Before Quotation

Published by Yuefu Electronic

A waterproof cable assembly quotation is only as useful as the environmental and interface details behind it. An IP marking on a sketch is not a complete requirement. The review needs to know how the cable is used, how it is sealed, and how the finished assembly will be tested.

This note is a practical RFQ checklist for overseas procurement and engineering teams preparing a sealed interconnect requirement. It explains which missing details usually delay a meaningful quotation.

IP rating vs actual application

An IP code classifies protection against access, solid objects and water under a stated standard such as IEC 60529. IP67 includes dust-tight protection and temporary immersion under specified conditions. It does not establish the service life of an assembly under every outdoor, chemical or washdown exposure; the specimen boundary and assembled state still need to be defined.

Write down the application before you write down the rating. Is the assembly exposed to rain, washdown, standing water, temporary immersion, or continuous outdoor use? Is it cleaned with chemicals? Does it see dust, sand, oil, or salt? Will the connector be disconnected in the field?

If you already have a target such as IP67, state the standard and the test method you expect, not only the code. Confirm whether the rating applies to the mated connector, the cable exit, the overmold, or the complete assembly. A connector family that can be specified to a rating still needs a defined cable interface, seal, and validation method.

An immersion test and a jet or washdown test address different exposure mechanisms. A requirement for both should identify both test scopes; do not assume an IP67 immersion result covers a pressurized cleaning process.

If the rating is not yet confirmed, say so. It is better to describe the exposure and let the review propose a construction and a test plan than to quote against an assumed code. Do not ask the factory to confirm a rating from a drawing alone.

For outdoor equipment, sensors, and vehicle-related electronics, put the application notes next to the drawing. The Waterproof Cable Assembly page lists the review points that usually come first: sealing target, housing, jacket, and environmental test criteria.

Jacket, overmold, and strain relief

The jacket is the first barrier and the part that sees abrasion, UV, oil, and flexing. Name the material if it is already approved, such as PVC, PUR, TPE, or another construction, and the reason it was chosen. If it is not approved, describe temperature range, chemical exposure, outdoor use, and whether the cable must flex in service.

Length, outer diameter limits, color, and shielding also belong in the RFQ when they are known. A sealed exit can fail if the jacket is too hard, too soft, too oily, or incompatible with the overmold or grommet material. If a cable is customer-specified, send the datasheet or the construction stack-up.

Overmolding is a construction choice, not a default. It can protect the termination, control the cable exit, and add strain relief. It also changes tooling, sample timing, and how a seal is formed. If you want an overmold, state the expected shape, hardness range if known, color, and whether the overmold is only mechanical or also part of the sealing method.

Strain relief can be an overmold, a molded boot, a clamp, or a connector backshell. Say which approach you expect, or say that it is open. Include the minimum bend radius, the direction the cable leaves the connector, and any pull, twist, or repeated flexing at the exit.

These details also matter when a standard cable assembly later needs a sealed transition. Do not assume the jacket and exit used inside a cabinet will work outdoors or on moving equipment.

Connector sealing

Connector sealing is usually several features working together: the mating interface, the housing, the rear seal or grommet, and the cable or overmold behind it. A sealed connector part number is useful. It is not the whole specification.

Send the connector part number, manufacturer, and mating counterpart when you have them. If alternatives are allowed, say so. If the connector must be customer-specified with no substitute, write that into the brief. A photograph can help an early discussion, but the part number and mating interface are more useful for production review.

Describe the cable exit, rear seal, potting, or overmolded backshell. Note whether the connector is mated during water or dust exposure. An unmated sealed connector and a mated assembly are different test cases. Also note locking method, keying, and whether the housing will see UV, chemicals, or repeated mating cycles.

If the project is closer to a custom wire harness with a sealed breakout, say where the branches leave the main jacket and how those exits are protected. Branch points, splices, and identification sleeves are common leak paths and should appear on the drawing or wiring list.

Test requirements

A sealing claim should be tied to a test, not to a catalog phrase. State what you want checked on samples and what you want checked on production lots. Those two scopes are often different, and the quotation should not treat them as the same work.

Typical items include continuity and short testing, visual inspection of the overmold and seals, pull force at the cable exit, and a defined ingress test. If you require an IP test, specify the standard, severity, duration, water type if relevant, and whether the sample is mated. If you require leak, pressure, or another method, name it.

Also state what records you need: a sample report, a lot inspection record, photographs, or dimensional checks on critical features. If a sampling plan or a defect-rate target already exists, include it. If it does not, leave it as an open point rather than implying a factory default.

Do not ask the quotation to confirm a waterproof rating from a drawing alone. The first review should confirm the test method, the sample quantity, who performs the test, and what happens if a result falls outside the agreed criteria.

Sealing boundary: define what is waterproof

Before using the word waterproof, name the boundary: the mated connector face, the cable tail or exit at the back of the connector, or the complete finished assembly including the overmold, backshell, splice, and enclosure entry. These are different review boundaries. If only the mating face is in scope, the quotation should not imply that the cable tail or the rest of the assembly has the same protection.

Writing "IP67" on a drawing identifies a standardized protection class when tied to the applicable standard, but it does not identify the actual specimen boundary or mating configuration. Record whether the tested item includes the rear cable exit and enclosure entry, and which report demonstrates compliance.

Exit direction and jacket construction can create a leak path. A downward or side exit changes where water collects; a bend too close to the seal can load the rear seal; and a jacket outside diameter or material that does not match the grommet, overmold, or backshell can leave a gap or let water track along the cable. State the exit orientation, supported bend and strain relief, jacket construction, and where the seal is formed.

Example: the connector passes, the installation still leaks

Consider a mated connector tested with its specified cable and rear seal. Replacing the cable with a smaller outside diameter may leave insufficient seal compression. Alternatively, the mating face may stay dry while water enters an unsealed enclosure gland farther along the cable. In both cases, repeating the connector's catalog rating does not qualify the changed assembly. This is an illustrative failure path, not a reported customer case.

Record cable outside-diameter tolerance, seal contact location, permitted bend at the exit and installation support. Add any required preconditioning, such as flexing or thermal exposure, before the agreed ingress test. The jacket selection guide explains why a polymer name alone cannot establish sealing compatibility.

What to send for a quote

A useful waterproof cable assembly RFQ can be short if it is specific. The first review is meant to find missing information, not to guess it.

Send the latest drawing or cable layout and its revision. Include connector part numbers, the mating interface, cable construction or a target jacket, length, and the quantity for samples and production. Describe the application environment, movement, temperature, chemicals, and whether the connector is disconnected in use.

Add the sealing intent: overmold, grommet, potting, or backshell. Add the test intent: standard, method, sample quantity, and records. Attach PDF, CAD, or photographs of the installation if the drawing does not show the cable exit or the available space.

If any item is still open, label it as open. Unconfirmed ratings, unapproved jackets, and undecided test methods should not be written as if they were already agreed.

When the brief is ready, send it through the Request a Quote page. Include the drawing, connector part numbers, quantity, application, and the test requirements you already know.