M12 is a connector family, not a complete cable assembly specification. Procurement teams often write "standard M12 cable" and leave the coding, pin count, shielding, and application conditions open. The result is a quotation built on guesses, followed by samples that do not match the intended interface.
A useful M12 RFQ identifies what is already fixed and labels the rest as open. Start with the customer drawing, connector part number, or a measurable interface description, then add the wiring, cable, sealing, and inspection details below.
A, B, D, and X coding: state the intended use
A-coded M12 interfaces are commonly used for sensors, actuators, and general signal or low-voltage power connections. B-coded interfaces are often associated with fieldbus-related connections. D-coded interfaces are commonly used for industrial Ethernet and data connections. X-coded interfaces are intended for higher-speed Ethernet or data applications. These are application conventions, not substitutes for the actual part number and pinout.
Do not select a coding letter from the name alone. Confirm the keying, position count, mating counterpart, cable construction, and signal requirement. If the code or application is not frozen, mark it as open and ask the engineering review to compare the feasible options.
Pin count and the wiring table
"4-pin M12" or "8-pin M12" is not a wiring specification. Attach a pinout table with the pin or cavity number, circuit name, wire color or identification, termination at the opposite end, and any unused positions. State whether the view is from the mating face or the wire side so the pin order cannot be reversed during sample review.
A simple example might read: Pin 1 — supply; Pin 2 — signal; Pin 3 — return; Pin 4 — spare. This is only a format example, not a default M12 pinout. The controlled wiring table is what keeps the quotation, sample, and production tester aligned.
Shielding and grounding
If the cable is shielded, specify the shield construction when known and show how it terminates at each connector. State whether the drain, foil, or braid is bonded to the connector shell, chassis or functional earth, signal reference, or left open at one end. Do not assume that cable shield and signal ground are the same circuit.
Also state what must be checked: shield continuity, termination presence, insulation from signal conductors, or a customer-defined electrical test. If the grounding method is still under review, mark it as open instead of allowing the sample to establish an unintended default.
IP target and whether the connector is mated
An IP target needs a test boundary and a test state. Say whether the requirement applies to the mated connector face, the rear cable exit, the overmold or backshell, or the complete assembly. Include the exposure, test method, duration, sample quantity, and whether the connector is mated during the test.
A connector can be suitable for a sealed application while the finished cable exit, jacket transition, or enclosure entry still needs its own review. The M12 Cable Assembly page is the right place to start that interface discussion, but the RFQ should carry the project-specific test boundary.
Cable length, jacket, and exit direction
State the finished length and the measurement reference, such as connector end to connector end or connector mating face to the defined cable datum. Add the jacket material or target construction, outside diameter, color, flexibility, temperature, chemical exposure, and minimum bend requirement when known.
Cable exit direction is also part of the fit. Specify straight, right-angle, or another orientation, the direction relative to the key, and the strain-relief or backshell approach. A change in exit direction can affect bend radius, clearance, sealing, and the way the cable is supported in the equipment.
Sample checks versus production inspection
Sample approval and mass-production inspection are different gates. For a sample, the review may need fit and mating confirmation, pinout and continuity, finished length, cable exit, appearance, labeling, and the requested sealing test. For production, state which checks are required on every assembly and which are sampled by lot.
If crimp, pull-force, shield termination, continuity and short testing, dimensional checks, IP testing, or traceability records are required, name the method and the evidence you expect. Do not let a successful prototype sample stand in for a production inspection plan.
What to send for an M12 cable assembly quote
Send the latest drawing or wiring table, the M12 coding and position count, connector and mating part numbers, shielding and grounding intent, IP boundary and mated-state requirement, finished length, jacket or cable construction, exit direction, quantities for samples and production, and the inspection records you require. Mark unresolved items as open.
When the brief is ready, send it through Request a Quote. A structured M12 requirement gives the engineering review something specific to confirm instead of forcing the quotation and sample to guess.