IP67 and IP68 are two of the most commonly requested ratings in waterproof cable assembly projects, but they are also two of the most misunderstood. Many OEM RFQs list one of these ratings as a requirement without defining the real environment, sealing boundary, or validation method. That often leads to rework during sampling or field failures after launch.
This guide explains IP67 vs IP68 for waterproof cable assemblies from an OEM engineering and sourcing perspective. It focuses on what the ratings mean, what they do not mean, and how to specify them in a way that improves supplier alignment and field reliability.
If you are building the full waterproof design package, start with our Waterproof Cable Assemblies Design Guide for OEM Buyers and then use this article to refine your IP rating decision.
What IP67 and IP68 Mean for Cable Assemblies
IP ratings are ingress protection ratings used to describe protection against solid objects and water under defined test conditions. For waterproof cable assemblies, the rating is useful, but only when everyone agrees on what part of the assembly is being rated and under what test setup.
The important point for OEM buyers is this: an IP rating is not a universal durability guarantee. It is a performance result under specific conditions. A cable assembly can meet an IP rating in one test setup and still fail in field use if the real environment adds cable bending, pull force, vibration, temperature cycling, or contamination at the seal interface.
That is why IP67 and IP68 should be treated as specification inputs within a broader waterproof design and validation plan.
IP67 vs IP68 Test Difference for Waterproof Cable Assemblies
The practical difference between IP67 and IP68 is not simply “one is better.” The key difference is the immersion test condition and how it is defined.
In general OEM discussions:
- IP67 is commonly used for temporary immersion conditions under a standard test setup.
- IP68 is used for immersion conditions beyond the IP67 level, but the exact test depth, duration, and conditions must be defined by the manufacturer or agreed specification.
This is why IP68 can create confusion in sourcing. Two suppliers may both claim IP68, but they may not be testing to the same immersion conditions. If the RFQ says only “IP68,” you may get technically compliant quotes with very different real-world performance margins.
For waterproof cable assemblies, the rating target should always be paired with the intended test condition and sealing boundary.
IP Rating Scope for Waterproof Cable Assemblies
One of the most common mistakes is failing to define the scope of the IP rating. In cable assembly projects, the rating may apply to different parts of the system depending on how the product is designed.
OEM teams should clarify whether the IP rating applies to:
- the connector interface only,
- the complete mated cable assembly,
- the overmolded cable exit area,
- the panel-mounted interface with the cable assembly installed,
- or the final product system including the cable assembly.
Without this definition, supplier assumptions can differ. One supplier may rate only the connector mating interface, while another quotes a more complete assembly-level sealing solution. The price difference can look large even though both quotes appear to meet the same rating on paper.
If your product uses custom cable transitions or sealing around the cable exit, align the IP scope with your Overmolding Services plan early.
How OEM Buyers Choose IP67 or IP68
The right choice depends on the real environment and product risk, not on which number looks stronger in the RFQ.
A practical OEM selection process should consider:
- actual water exposure type (splash, washdown, temporary immersion, prolonged moisture),
- expected contamination (dust, oil, chemicals),
- cable movement during operation,
- installation orientation and drain behavior,
- service access and mating frequency,
- cost target and production volume,
- consequence of field leakage.
In many products, IP67 is fully sufficient if the real use case is splash or short-duration exposure and the sealing design is robust. In other products, IP68 may be appropriate—but only if the immersion condition is clearly defined and validated on the complete assembly.
For industrial applications, your Industrial & Robotics page is a useful internal reference when documenting the actual operating environment.
IP67 vs IP68 and Waterproof Connector Selection
Connector selection should not be separated from the IP rating discussion. A connector can be marketed for high ingress protection, but overall assembly performance still depends on cable OD fit, seal compression, locking stability, and installation handling.
When comparing IP67 vs IP68 options, OEM teams should review:
- connector sealing geometry,
- cable OD sealing range,
- locking method and vibration resistance,
- mating cycle stability,
- material compatibility with environment,
- tolerance sensitivity in production assembly.
This is especially important in custom cable assembly projects where the cable jacket and connector sealing hardware must work together. A strong connector rating cannot compensate for poor cable-to-seal matching.
We will expand this in Waterproof Connector Selection for Cable Assemblies.
IP67 vs IP68 and Sealing Method Selection
IP rating targets also affect sealing method selection beyond the connector interface. In many waterproof cable assemblies, the cable exit and transition zone can become the weak point, especially under bending, pull force, or repeated movement.
Depending on the target rating and environment, OEM teams may need to evaluate:
- overmolding,
- sealing boots,
- potting,
- gaskets or O-rings,
- heat-shrink sealing,
- combined multi-stage sealing methods.
The correct choice is not only about passing an ingress test once. It is about maintaining seal integrity through production variation and field use. This is where process repeatability and manufacturing control become critical.
We will compare these options in Overmolding and Sealing Methods for Waterproof Cable Assemblies.
IP67 vs IP68 Testing and Validation for OEM Buyers
For OEM buyers, the biggest risk is not choosing the wrong rating label—it is validating the right rating in the wrong way. A meaningful validation plan should reflect the real product environment and the defined rating scope.
A practical validation plan should clarify:
- what assembly state is tested (mated / installed / full assembly),
- test condition details used for the rating claim,
- whether mechanical stress is applied before or after ingress testing,
- acceptance criteria for leakage or functional failure,
- sample quantity and repeatability expectations.
If the product is exposed to vibration, bending, or frequent handling, consider testing conditions that reflect those risks rather than relying on a static ingress test only. For supplier approval and production alignment, use your Tests & Inspections and Quality Guarantee criteria as part of the RFQ package.
We will go deeper in Waterproof Cable Testing Guide for OEM Buyers.
Common IP67 IP68 Specification Mistakes in Cable Assembly RFQs
Several mistakes appear repeatedly in OEM RFQs.
One common mistake is writing only “IP68 waterproof cable assembly” with no test condition details. Another is defining the connector rating but not defining whether the complete cable assembly or cable exit sealing must meet the same requirement.
Some teams also select IP68 by default for marketing reasons even when the real application only needs splash or temporary immersion resistance. That can increase cost and limit connector choices without improving real field reliability.
Another costly mistake is approving samples based on rating claims alone without documenting the exact test method used by the supplier. Two samples can both be labeled IP68 and still represent different risk levels in production.
OEM RFQ Tips for IP67 and IP68 Cable Assemblies
A stronger RFQ reduces confusion and improves quote quality. Do not stop at the rating number.
A practical RFQ for IP67 or IP68 waterproof cable assemblies should define:
- target IP rating,
- rating scope (connector only or complete assembly),
- intended test condition details for IP68 (if required),
- tested assembly state (mated / installed / complete build),
- cable jacket material and OD range,
- connector type or approved alternatives,
- sealing / overmolding expectations,
- mechanical stress conditions in use,
- validation and inspection requirements,
- field risk notes or past failure history.
If you already have sample photos or drawings, include images of the connector interface and cable transition area. This often improves supplier interpretation and helps avoid under-scoped quotes.
For custom project alignment, your Custom Cable Assemblies and Strong Technical Support pages are useful internal references.
Conclusion
IP67 vs IP68 for waterproof cable assemblies is not just a higher-number decision. The right choice depends on the real environment, the defined rating scope, the connector and sealing design, and the validation method used for supplier approval.
For OEM buyers, the best results come from specifying not only the rating label, but also the test intent and assembly scope. That approach reduces ambiguity, improves supplier comparison, and creates a better foundation for field reliability.
FAQ
Is IP68 always better than IP67 for waterproof cable assemblies
Not automatically. IP68 is not simply “better” in every project. The right choice depends on actual exposure conditions, cost targets, connector options, and whether the IP68 test condition is clearly defined for the application.
Why is IP68 more confusing in OEM sourcing
Because the exact immersion conditions for IP68 must be defined by the manufacturer or agreed specification. Two suppliers can both claim IP68 while using different test depths or durations.
Should the IP rating apply to the connector or the whole cable assembly
That must be defined in the RFQ. In some projects the rating is for the connector interface only, while in others the complete cable assembly or cable exit sealing must meet the requirement.
Can a cable assembly pass IP67 or IP68 and still fail in field use
Yes. Field failures can still happen if the test scope does not match real conditions such as bending, vibration, contamination, pull force, or temperature cycling.
What should OEM buyers add to an IP67 or IP68 cable assembly RFQ
Add the rating scope, test condition intent, tested assembly state, connector and cable assumptions, sealing method expectations, and validation criteria. This reduces ambiguity and improves quote quality.
CTA
Need Help Choosing IP67 or IP68 for a Waterproof Cable Assembly Project
If your team is deciding between IP67 and IP68 for an OEM cable assembly, we can help review the requirement before RFQ release or sample approval.
We can support:
- IP rating scope definition for the full assembly,
- connector and cable sealing match review,
- overmolding and sealing method review,
- OEM validation and inspection planning,
- supplier quote comparison from a field-reliability perspective.
If you already have drawings, connector part numbers, or sample photos, contact us through our Contact page. You can also review our Waterproof Cable Assemblies Design Guide for OEM Buyers, Overmolding Services, and Tests & Inspections pages before starting the discussion.
