Industrial Engineer · phase 13 of 16 · noun

Shielded VFD Cable

Motor cable designed with suitable insulation and a continuous low-impedance shield or armor for PWM drive service.

The Explain card

Plain English
VFD cable is motor cable built for PWM. It has insulation rated for the voltage peaks, a continuous copper shield or armor, and usually three symmetrical ground conductors, so the high frequency current has a low impedance path back to the drive.
Example
A drive is installed with ordinary building wire in conduit. Nearby instruments misbehave, the ground fault trips, and the motor bearings fail. The cable is replaced with shielded VFD cable and all three problems ease.
Why it matters
The cable is the return path for common mode current, and an unshielded run turns the whole plant grounding system into that path. Buying the right cable is cheaper than diagnosing what the wrong one does.
Hook
The cable is part of the drive.

Word knowledge

How the word is built, where it came from, and what it sits beside in memory.

In a sentence

Route Shielded VFD Cable from the drive output terminals to the motor, then bond the shield using 360-degree cable glands.

Why these words
  • shielded Old English scield, shield, plus the suffix -ed participial adjective modifying cable
  • VFD initialism of variable frequency drive initialism specifying the cable's application
  • cable Old North French cable, from Medieval Latin capulum, rope or lasso head noun of the phrase
Where it came from
Origin
English technical compound combining shielded, the initialism VFD, and cable
Entered the language
20th century
What changed
Shield developed a verbal use, its participle became an adjective, VFD compressed a technical equipment name, and cable expanded from rope to electrical wiring.
How it is spelled
Pattern
The regular suffix -ed marks shielded as a participial adjective.
Pattern
VFD keeps all three letters capitalized as an initialism.
Pattern
Shielded and cable are normally lowercase in running text.

Spelled like

  • grounded
  • screened
  • PLC
  • HMI
Broken into chunks
  • shield
    • shielding
    • unshielded
  • VFD
    • VSD
    • ASD
  • cable
    • cabling
    • cabled
What it sits beside

Same subject

  • variable frequency drive
  • PWM output
  • motor leads
  • EMC cable gland
  • common-mode current

drive output circuit terms

EMC installation terms

  • 360-degree shield termination
  • EMC cable gland
  • bonding conductor

Where it sits in the deck

Phase 13: VFD Power Quality, Wiring, and Motor Protection

Harmonics, reflected waves, shielded cable and bearing currents: the side effects a drive inflicts on everything around it.

Neighbours in this phase