Industrial Engineer · phase 12 of 16 · noun

Braking Resistor

Resistor sized to absorb regenerated energy and limit DC-bus voltage during dynamic braking.

The Explain card

Plain English
The braking resistor is the load the chopper switches across the DC bus. It has to absorb the energy of each stop and shed it as heat before the next one.
Example
A resistor for a conveyor drive is rated for a peak of 20 kilowatts and a duty of 10 percent. It handles one hard stop every minute and would overheat on one every ten seconds.
Why it matters
Resistors are sized by energy and duty cycle rather than by drive horsepower, and a wrong one either trips the drive or burns. It also needs a thermal switch wired back so an overheated resistor stops the drive rather than the building.
Hook
The place the stop goes to die.

Word knowledge

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

In a sentence

During commissioning, the technician connects the Braking Resistor to the drive terminals and verifies its resistance before running a rapid deceleration test.

Why these words
  • braking English brake plus -ing modifies resistor by identifying its use during braking
  • resistor English resist plus the instrument suffix -or names the electrical component at the head of the phrase
Where it came from
Origin
English technical compound formed from braking and resistor
Entered the language
20th century
What changed
Braking developed from the action of applying a brake, while resistor became the standard electrical name for a component characterized by resistance.
How it is spelled
Pattern
brake drops its final silent e before the suffix -ing
Pattern
resistor uses the instrument suffix -or
Pattern
the modifying noun form precedes the head noun

Spelled like

  • making
  • driving
  • contactor
  • reactor
Broken into chunks
  • brak
    • brake
    • brakeman
  • resist
    • resistance
    • resistive
  • or
    • contactor
    • reactor
What it sits beside

Same subject

Same shape

  • braking unit
  • load resistor
  • bleeder resistor
  • precharge resistor

VFD braking hardware

industrial resistor types

  • braking resistor
  • precharge resistor
  • bleeder resistor

Where it sits in the deck

Phase 12: VFD Commands, References, and Stopping

Starting, referencing and stopping, including the several very different things a drive can mean by the word stop.

Neighbours in this phase