How to know if CAT6 cable and keystone jacks are garbage or not?

Practical Tips for Identifying Inferior CAT6 Network Cables and Keystone Jacks

I. Distinguishing Network Cable Quality at a Glance

• Copper Core Material Trap

Genuine: Oxygen-free copper core (purplish-red, flexible and reflective)
Fake: Copper-clad aluminum (grayish-white cross-section, easily broken)
Easy Test: Scrape open the core – gold = copper, silver = aluminum

• Cheap Twist Pitch

Four pairs of twisted wires should have different twist densities (key to interference prevention)
Inferior Cable: Loose twist pitch or all four pairs are the same (prone to packet loss)

• Hidden Features in Sheath Material

Good Cable: Flame-retardant outer sheath (self-extinguishing after 3 seconds with a lighter)
Bad Cable: Flammable PVC sheath dripping (fire hazard in server rooms)

II. Keystone Jack Thorough Inspection

• Gold Content of Contacts

Qualified: Phosphor bronze plated with 50μm gold (thick contacts, full gold color)
Junk: Thin gold-plated iron sheet (exposed after 5 plug-and-play cycles) • Base color, oxidized and blackened)

• Plastic shell strength

Genuine: High-strength PC material (no white mark when pinched with a fingernail)
Inferior: Recycled material (pungent odor, easily broken)

• IDC blade sharpness

High-quality: Stainless steel blade (crisp "click" sound when pressing wires)
Inferior: Dull blade (requires repeated heavy pressure, wire core is flattened)

III. Mandatory tests for combined use

• Continuity test (basic but fatal)

Using a ¥20 wire tester: All 8 lights on ≠ qualified (must be tested completely) (10 plug-in/unplug test)
Inferior Keystone: Light flashes/goes off after the 3rd plug-in/unplug test

• Gigabit bandwidth verification

Copying a 10GB file: Stable transfer ≥90MB/s (true gigabit)
Inferior combination: Large speed fluctuations (30~90MB/s fluctuations)

• PoE power supply stress test

Connecting an IP camera/AP: Full power operation for 1 hour
Junk cables: Connectors overheat and soften (dangerous!)

IV. Guide to exposing merchant tricks

Promotional rhetoric, truth, and countermeasures
“Leftover materials from engineering projects sold at low prices”: Mostly substandard or cut-off stock. Request original packaging + batch number.
“Category 6 10 Gigabit standard”: No certification = false advertising. Check UL/ETL markings.
“Imported gold-plated contacts”: May only be plated to 0.1μm. Request a plating test report.

V. Survival-level self-inspection steps

• Look: Is the printing on the cable clear? (True CAT6 must have CMR/CMP fire rating markings.)
• Pry: Keystone jack snaps into the panel—inferior. It breaks with a snap.
• Burn test: Cut a 1cm section of wire and burn it—the copper core melts into a ball, and the copper-clad aluminum sparks.
• Test test: Connect an old mobile phone charger to a PoE splitter—it should supply power normally when plugged into the Keystone port.