Industrial Engineer · phase 10 of 16 · noun
DC Bus Voltage
Voltage on the DC link, typically near 1.35 to 1.41 times the AC line-to-line RMS voltage depending on rectifier topology, loading, and ripple.
The Explain card
- Plain English
- The bus voltage is the DC level between the rectifier and the inverter. On a plain diode front end it sits a little below the peak of the incoming line, which is about one and four tenths times the RMS line to line voltage.
- Example
- A 480 volt supply gives a bus near 650 volts DC at light load. During a hard deceleration the same bus climbs toward 800, and an overvoltage trip lands around there.
- Why it matters
- Nearly every voltage fault on a drive is a bus fault. High means regeneration or a high line, low means a sag, a lost phase or a tired capacitor, and the keypad's bus reading is the first diagnostic.
- Hook
- The one voltage inside the drive that tells the story.
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 measures DC Bus Voltage at the drive terminals before checking the inverter stage.
Why these words
- DC English initialism of direct current identifies the electrical domain being measured
- bus English shortening of busbar, ultimately from Latin omnibus, for all names the shared conductor or connection point
- voltage volt, named for Alessandro Volta, plus the suffix -age names the measured electrical quantity
Where it came from
- Origin
- English engineering compound formed from DC, bus, and voltage
- Entered the language
- 20th century
- What changed
- Bus moved from a shortening of omnibus to a shared electrical conductor, while voltage developed from volt as the name of an electrical quantity.
How it is spelled
- Pattern
- DC remains uppercase and unpunctuated
- Pattern
- bus voltage is written as an open compound
Spelled like
- AC bus voltage
- DC link voltage
- DC bus current
Broken into chunks
-
DC
- DC link
- DC supply
-
bus
- busbar
- fieldbus
-
volt
- voltmeter
- voltaic
-
-age
- amperage
- wattage
What it sits beside
Same subject
- DC link
- rectifier
- inverter
- braking chopper
- variable frequency drive
Same shape
- AC Bus Voltage
- DC Link Voltage
- DC Bus Current
drive electrical measurements
- DC Bus Voltage
- output current
- line voltage
DC-link components
- bus capacitor
- braking chopper
- precharge resistor
Where it sits in the deck
Phase 10: VFD Electrical and Motor Fundamentals
The physics under the parameters: slip, torque, flux, and the relationship between frequency and voltage that every drive is really controlling.
