Keeping a comprehensive custom industrial cable specification checklist early on in your OEM motion system project helps to avoid re-design, prototyping delays and field failures—all of which can cost you a lot. Cables are used in high cycle applications such as robotic arms, CNC machines or automated guided vehicles are used in high cycle applications, where they are subject to continuous flexing, torsion, vibration and exposure to extreme environments. RFQs like “high flex 4 core cable” leave too much room for misinterpretations, which results in sub-optimal solutions or multiple rounds of solution iterations.
This practical custom industrial cable specification checklist offers OEM engineers and technical buyers a guide to the key parameters. From the experience gained over 20 years of manufacturing servo, robot and drag chain cables, we help teams to come up with clear specifications that help in providing accurate quotes, quick sampling time and better long term performance in real motion control systems.
Step 1 – Define the Application and Motion Profile
The first step in making any decision about a cable is to determine where and how the cable will be used. In doing so, this context can help cable engineers to plan for the best possible construction of the project since the beginning.
Machine Type, Function and Cable Role
Describe the overall machine, whether it is a 6 axis robot, linear gantry, packaging line or an AGV and the function of each cable. Is it providing power to servo motors, feedback from encoders, Ethernet signals or mixed hybrid functions? This information is valuable to predict the location of electromagnetic interference sources, duty cycles, and physical routing considerations which directly affect the design of the cable.
Motion Type: Fixed, Flexing, Continuous Flex or Torsion
Distinguish between clearly fixed installation, occasional flexing, continuous drag chain travel and multi-axis torsion in robotic dress packs. Provide necessary input parameters like travel distance, velocity, acceleration, cycles per day/year, and torsion angle per meter. These are very important for choosing the right flex life, correct stranding type, shielding materials and jacket type to ensure no conductor breakage or degradation of the shield.
Step 2 – Electrical Requirements and Conductor Design
Correct electrical details guarantee that the cable can appropriately and safely carry power and signals in dynamic circumstances.
Voltage, Current and Conductor Size
Set maximum system voltage, continuous and peak currents and if the cable is for AC, DC or PWM signals from frequency inverters. This determines conductor cross-section selection, the thickness of the insulation and, if required, the derating of the bundled or enclosed installations. There is a risk of overheating or voltage drop over long distances if this is not set correctly.
Number of Cores, Pairing and Signal Types
Specify the exact number of cores and configuration (power cores, twisted pair signals, encoder cables, fieldbus, Industrial Ethernet elements (CAT5e to CAT7A), etc.). Determine the circuits that need to be individually protected, have to be controlled by the impedance requirements, or have to be integrated with the brake, temperature sensor or other auxiliary conductors. Here, signal integrity problems in motion control applications are avoided by having clear definitions.
Step 3 – Shielding, EMC and Noise Environment
Electromagnetic compatibility is a critical issue in motion systems that frequently have high power drives and sensitive sensors.
Noise Sources and Required Shielding Level
Identify sound sources in the immediate vicinity (servo drives, inverters, welding etc or high currents buses) Set acceptable noise margins for connected devices. Think about protection methods like overall braid, foil and braid, individual pair shielding, drain wires and target coverage percentages. The right choice of shielding ensures a constant signal quality for millions of flex cycles.
Grounding, Separation and Termination Constraints
Outline Shield Termination Methods – Preferred 360° Clamps – High frequency performance, if required, may share a single cable with power cores, and any grounding requirements set by the drive manufacturer / robot manufacturer. These decisions will impact on the overall diameter, flexibility and connector compatibility of the cable.
Step 4 – Mechanical and Geometric Constraints
The final construction of the cable may be determined more by physical factors than electrical.
Outer Diameter Limits, Bend Radius and Space Envelope
Offer maximum outer diameter to fit into cable glands, drag chains and robot dress packs. Add mechanical design requirements such as minimum bend radius. Advanced flexible stranding and/or special jacket compounds can be required for tight envelopes to ensure performance.
Required Flex-Life and Mechanical Loads
Define the target service life in cycles or operating years, along with any additional mechanical stresses such as tensile loads in vertical runs, crushing forces, or repetitive impacts. Realistic life targets allow selection of optimized conductor stranding and reinforcement layers that match your application’s demands.
Step 5 – Environmental and Chemical Conditions
Cables must survive the same environment as the machine they serve.
Temperature Range, Moisture and UV
State the full ambient temperature range, including hot spots near motors or ovens, presence of condensation, washdown requirements, and any outdoor or UV exposure. These factors determine insulation and jacket material choices, such as high-temperature silicone cables rated from -60°C to +200°C for extreme conditions.
Oils, Coolants, Chemicals and Special Hazards
List expected exposure to cutting oils, coolants, hydraulic fluids, solvents, food-grade cleaners, welding spatter, dust, or abrasives. Different jacket materials — PUR, TPE, halogen-free, or silicone — offer varying resistance. Specifying these early avoids jacket cracking or swelling that leads to premature failure.
Step 6 – Regulatory, Safety and Customer Standards
Compliance requirements must be captured upfront to avoid certification delays.
Required Approvals and Flame Ratings
List all mandatory certifications: UL/cUL, CE, TÜV, IEC, RoHS, REACH, NFPA 79, or others relevant to your target markets. Include flame and smoke ratings (VW-1, FT4, LSZH) when required by end-user specifications or building codes.
Company or End-User Specifications
Include any internal standards such as preferred jacket colors, marking formats, traceability requirements, or mandated component suppliers. Sharing these details prevents later revisions after initial samples are approved.
Step 7 – Quality, Testing and Documentation Expectations
Consistent quality expectations mean that all production runs are consistent.
Routine Production Tests and Type Tests
Set up required electrical tests (high-pot, continuity, insulation resistance) for each batch, and any special type tests that are required (flex-life, torsion, drag chain validation, etc.). Set acceptance criteria and if a formal test report is to be included with each shipment.
Quality System, Traceability and Change Control
Check the ISO 9001 or equivalent quality management system of the supplier, lot traceability and procedure for design changes and material substitutions. Ask for clear documentation and drawings, including revision control and bills of materials, to aid long term field service.
Step 8 – Commercial and Logistics Considerations
The specification is supplemented by practical information and aids in smooth procurement.
Volumes, Length Variants and Packaging
Calculate annual quantities, minimum quantities and also length options (bulk reels, cut to length or pre-terminated assemblies). Indicate tolerances for the length, reels, and any special packaging requirements like clean room bags or labeled drums.
Lead Times, Samples and Localization
Target lead times, prototype or pre-production samples needed, and regional stocking or Just-in-Time delivery required. Mark if engineering support or on site assistance at initial machine build would be helpful.
Ready-to-Use OEM Cable Specification Checklist
Use this structured checklist as a template when creating your next Custom Industrial Cable RFQ:
Application & Motion
- Machine type and cable function (power, control, feedback, Ethernet, etc.)
- Single motion or multiple (flexing / continuous drag chain / torsion)
- The distance between two points, rate of travel, and the increase or decrease in speed per day/year.
- Torsion angle per meter (for robotic applications)
Electrical
- The system voltage, continuous/peak current, AC/DC/PWM are displayed.
- How many cores, which cores are paired and what kind of signals are there.
- Twisted pairs, impedance control or additional conductors (auxiliary)
Shielding & EMC
- Sources of noise nearby and necessary noise immunity
- Type and coverage (braid, foil, individual pairs) of shielding materials.
- Grounding and/or termination preferences.
- Power/signal separation requirements
Mechanical
- Maximum outer diameter
- Minimum bend radius
- Target flex life (cycles) and other mechanical loads (tensile, crush, impact)
Environment
- Temperature range (min/max)
- Moisture, washdown, U.V. exposure.
- Exposing to oils, coolants, chemicals or abrasives
Standards & Quality
- Essential certification (UL, CE, TÜV, etc.)
- Flame/smoke ratings
- The need for testing (routine and type testing)
- The following are the expectations regarding quality system, traceability and documentation:
Commercial
- The volume and MOQ can be determined on an annual basis.
- Variations in length and tolerances
- The lead time and sample requirements.
- The packaging and delivery preferences will be noted.
This custom industrial cable specification checklist will simplify communication with the manufacturer and ensure the cable will reliably serve your OEM motion system.
Hulk Electric is specializing in providing custom industrial cables for servo, robot, drag chain and Industrial Ethernet applications, based on detailed specification. This in-house testing laboratory, the trained team of engineers, and lean manufacturing processes make it possible for OEMs to realize motion projects with less shock and less delay.
Submit your finished checklist or project brief to us; our team will give you quick technical feedback and sample support.