Performance category
Confirm Cat5e/Cat6 in the part specification rather than inferring an absent category from its name.
I/O Connector products
Cat3 RJ45 Inline Couplers
A Cat3 coupler joins two cable runs on legacy voice and low speed data links. Cat3 is the oldest category still in service, so confirm what the installed cable actually is before assuming a coupler at this grade is adequate for the link.
Part number search & selector
Find Cat3 RJ45 Inline Couplers part numbers
The table uses the current English-site product records, published selection fields and part-specific technical-file links.
* Frozen Image and Part Number columns · drag horizontally to review all specifications
| Image | Datasheet | Compare | Downloads |
Network Level
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Transmission Bandwidth
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Shield
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Gold plating of contacts
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Panel
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Sample |
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| Image | Part number | Datasheet | Compare | Downloads | Network Level | Transmission Bandwidth | Shield | Gold plating of contacts | Panel | Sample |
|---|---|---|---|---|---|---|---|---|---|---|
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WHZT3811EK0042P8111059 | SPEC | Cat3 | 16MHz | YES | 6U | NO |
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No matching part numbers
Broaden the selected filters or clear the current search.
Product family quick links
Start with Network Level
Counts reflect the current published product data.
How to select
A practical selection sequence
Narrow the published fields in sequence, compare the remaining candidates and verify the part-specific files before design-in.
- 01
Confirm straight-through or special wiring
Specify both interfaces, gender and contact mapping; assess any one-to-two adapter separately.
- 02
Match the cabling category
Choose documented Cat5e or Cat6 candidates for the channel; missing fields are not a pass.
- 03
Choose shielding and mounting
Review shield grounding, panel retention, cutout and cable clearance.
- 04
Validate the channel and request supply
Test at the intended length, data rate and power conditions, then send the part number, quantity and timing for a quote.
Key selection parameters
What each filter helps you decide
Frequency bandwidth
MHz describes frequency, not achieved data rate in Mb/s.
Shielding
Review shield continuity and grounding across the coupler, cables and equipment.
Panel mounting
Check clips/fasteners, cutout, panel thickness and access on both sides.
Contacts and wiring
Verify plating location and units and contact mapping; a one-to-two adapter is not an ordinary inline coupler.
Product family comparison
Compare the published Network Level
Use this summary as a routing step, then verify every required value in the exact part-number row and linked technical files.
Return to the selector ↑Technical performance & application fit
Validate the complete design context
Application suitability is part-number specific. Treat the catalog fields as a shortlist, then confirm the design against the linked technical files.
Equipment panel feedthroughs
- Check panel retention and mating clearance when connecting internal and external cables.
Equipment cable connection and service
- Confirm wiring and category and reassess the complete channel after adding a connection.
Downloads & technical resources
Find files by part number
Search a full or partial SKU, then open its datasheet, 3D model or PCB footprint without returning to the product table.
Showing representative available file sets. Search to find a specific SKU.
- 1
- PDF datasheets listed
- 0
- 3D file sets listed
- 0
- PCB footprints listed
VOOHU’s published product content is reviewed by its engineering team. Specifications, downloads and technical support information are tied to specific part numbers, so you can verify them before requesting samples or a quotation.
Category overview
What an inline coupler does to the link
Couplers are simple parts, but two questions come up constantly: whether they slow the link, and which category to use.
Discuss a new design
Contact FAE for a replacement assessment.
Already have a part number? Request samples or a quote.
It joins two runs without re-terminating
A coupler mates two RJ45 plugs back to back, so two existing cable runs become one channel without cutting and re-terminating either end. That is its whole purpose: extending or repairing a run with existing patch leads rather than making up a new cable.
Does it slow the connection
Not in the sense people usually mean. A coupler does not reduce the negotiated link speed. It adds a connection point, which introduces an impedance discontinuity and a small insertion loss. On a short gigabit run that sits inside the margin. Near the length limit, or at 10G, it consumes margin already thin.
Match the category to the channel
The channel performs to its weakest element, so a Cat5e coupler caps a Cat6A channel at Cat5e. Use a coupler at or above the category of the cable and the link. On screened installations, use a shielded coupler so the screen stays continuous through the join, or the shielding is defeated at that point.
FAQ & related guides
Questions before design-in
These answers guide the page workflow. Part-specific engineering limits still come from the linked technical files.
What is a Cat3 coupler used for?
Joining two runs of Cat3 cable on legacy voice circuits and 10Base-T Ethernet. Cat3 is rated well below the categories used for modern data links, so it belongs in telephony and older installations rather than anywhere carrying gigabit or faster traffic.
Can I use it on a gigabit link?
No. Cat3 is not rated for the bandwidth gigabit Ethernet requires, and a coupler at this grade becomes the weakest point in the channel. If the link carries gigabit, use a coupler rated at Cat5e or above, and check the cable itself is rated for the speed.
Does the coupler category have to match the cable?
The coupler should be at least the category of the cable and the link. A lower grade coupler caps the whole channel at its own rating regardless of how good the cable is. Matching or exceeding the cable category is the safe rule.
Will a coupler affect the link at all?
Every inline join adds an impedance discontinuity and a small amount of loss. At Cat3 speeds that is rarely measurable. At higher categories it matters more, which is why coupler category and installation quality both become significant as link speed rises.
How do I request samples or a quote?
With a complete part number, send the part number, quantity, delivery region and the date you need it. If you are still selecting, send the cable category, the link speed and whether the coupler needs shielding.
Engineer support
Continue after product selection
Send the candidate part number and the condition you need reviewed. Sample support can be added after the selection is clear; commercial questions may be discussed in the same engineering conversation.
- 1Selected part numbers
- 2Engineering review
- 3Sample request
- 4Commercial discussion
For a replacement review
- Original part and datasheet
Include the document revision
- Operating conditions
Temperature, isolation voltage and PoE current basis
- Package constraints
Pin count, pitch and spacing between pin rows
- Project stage and annual volume
To help prioritize samples and evaluation
- Target review date
When you need candidates and a comparison of differences
Engineering review identifies candidate parts and explains the differences.
For samples and a quotation
- Candidate part numbers
From the selector or engineering review
- Quantity and project stage
Prototyping / pilot build / production
- Required delivery date
Specify sample and production timing separately
- Required documentation
Compliance documents, material declarations or third-party reports
Samples are free of charge. Sample quantity and lead time depend on the part number and project stage. Sales will respond on business days.
Published replacement reviews
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