Breakers & MCCB Flashcards
1
Q
Name 4 trips on a breaker
A
- Under V
- Over I
- Anti-shock
- Position interlock
2
Q
Brreaker
What 3 levels does the over current breaker have?
A
- Long time delay
- Short time delay
- Instantaneous
3
Q
What does the Position interlock breaker do?
A
Stops breaker being racked in or out
4
Q
What 2 ways can a breaker be operated?
A
- Manual
- Automatic
5
Q
What 5 maintenance routines should be done on breakers?
A
- Inspect earth bonding
- Measure earth bonding
- Clean & inspect
- Insulation resistance test
- Clean cubicle
6
Q
Name 4 defects found on breakers
A
- Blown fuses
- Discrepancy switches broken
- Limit switches broken
- Jammed breaker
7
Q
What 2 frame sizes do MCCB’s come in?
A
- 100 amp
- 250 amp
8
Q
Name 5 safety devices on MCCB’s
A
- Thermal mag trip
- Manual trip
- Electro-mag trip
- Current limiting fuses
- Residual current devices
