Industrial Engineer · phase 14 of 16 · noun
DC Bus Overvoltage
Trip caused when DC-link voltage rises above its safe limit, often during rapid deceleration or high line voltage.
The Explain card
- Plain English
- A bus overvoltage trip fires when the DC link rises past its safe limit. The usual cause is the motor regenerating faster than the drive can absorb, and the other one is a high incoming line.
- Example
- A fan is set to decelerate in five seconds. The bus climbs past 800 volts on the way down and the drive trips, leaving the fan to coast.
- Why it matters
- It is the most common fault on drives with fast ramps and heavy loads. The cures are a longer deceleration, stall prevention, a braking resistor, or a regenerative front end, and the fault history tells you whether it happens on stops or at random.
- Hook
- The energy came back and had nowhere to go.
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 traced a DC Bus Overvoltage alarm to an aggressive deceleration ramp on the variable frequency drive.
Why these words
- DC English initialism of direct current identifies the direct-current portion of the circuit
- bus English electrical shortening of busbar, ultimately related to Latin omnibus, for all names the shared electrical conductor or connection point
- overvoltage English compound of over and voltage classifies the condition by comparing voltage with an upper threshold
Where it came from
- Origin
- English technical compound combining the initialism DC with the electrical terms bus and overvoltage
- Entered the language
- 20th century
- What changed
- Bus acquired a specialized common-conductor sense, and voltage became productive in compounds such as overvoltage and undervoltage.
How it is spelled
- Pattern
- DC remains uppercase because it is an initialism.
- Pattern
- Overvoltage is written as one word because over- forms a closed compound with voltage.
- Pattern
- The phrase is commonly written with spaces between DC, bus, and overvoltage.
Spelled like
- DC bus undervoltage
- DC link overvoltage
- AC bus overvoltage
Broken into chunks
-
DC
- DC link
- DC drive
-
bus
- busbar
- busway
-
over
- overcurrent
- overtemperature
-
volt
- voltmeter
- voltage
What it sits beside
Same subject
- DC link
- braking resistor
- deceleration ramp
- regenerative braking
- variable frequency drive
Same shape
- overcurrent
- overtemperature
- overfrequency
drive protection terms
- DC Bus Overvoltage
- DC bus undervoltage
- output overcurrent
DC-link components
- rectifier
- DC-link capacitor
- braking chopper
Where it sits in the deck
Phase 14: VFD Safety, Faults, and Diagnostics
What a drive does when it trips, what the fault codes are telling you, and how safe torque off stops the motor without killing the panel.
