Mini 4P Thermal Magnetic Molded Case Circuit Breaker With
Electrical Generators
GENERAL
STM1 Moulded case ciecuit breaker is suitable for circuit AC
50HZ/60HZ, rated voltage up to AC 660V,rated operating current to
630A.It features normal structure,reliable performance,compete
accessories & high breaking capacity, used foe power
distribution and protecting the circuit and electrical equipment
against overload and short circuit. It complies with standard of
IEC 60947-2 and GB14048.2
Specifications
| Frame size rated current(A) | Circuit rated current | Rated current at N-pole | Frame size rated current | Circult rated current | Rated current at N-pole |
| 63 | 10 | 10 | 225 | 100 | 100 |
| 16 | 16 | 125 | 100 |
| 20 | 20 | 160 | 100 |
| 25 | 25 | 180 | 100 |
| 32 | 32 | 200 | 100 |
| 40 | 40 | 400 | 225 | 125 |
| 50 | 50 | 225 | 225 |
| 63 | 63 | 250 | 225 |
| 100 | 25 | 25 | 315 | 225 |
| 32 | 32 | 350 | 250 |
| 40 | 40 | 400 | 250 |
| 50 | 50 | 400 | 250 |
| 63 | 63 | 630 | 500 | 315 |
| 80 | 63 | 630 | 350 |
| 100 | 63 | | |
Molded case circuit breakers can have very high current ratings, which allows them to be used
in heavy duty applications. The following are some typical uses of
an MCCB:
- Main electric feeder protection – The electric feeder circuits that supply power to large
distribution boards normally have very high currents, of hundreds
of amperes. In addition, if more circuits are added to the system
in the future, it may be necessary to adjust the circuit breaker
trip settings. Therefore, a molded-case circuit breaker is
required.
- Capacitor bank protection – Capacitor banks are a very important component of commercial and
industrial electrical systems, since they allow power factor
correction – reducing line currents and preventing fees from the
electric utility company. Large capacitor banks may draw high
currents and will require MCCB protection.
- Generator protection – Large electrical generators may provide an output of hundreds of
amperes. In addition, gen-sets are normally very expensive. The
high current ratings of molded case circuit breakers allow them to provide reliable protection in this application.
- Welding applications – Some welding machines may draw very high currents that exceed
the capabilities of miniature circuit breakers, requiring the use
of an MCCB.
- Low current applications that require adjustable trip settings – MCCBs are not only for high current applications. There are models
rated below 100 amperes for when low current equipment requires the
adjustable trip settings provided by MCCBs.
Motor protection – The reliable protection capabilities of MCCBs make them an
adequate choice for motor protection. A molded case circuit breaker can be adjusted to provide overload
protection without tripping during the inrush current of an
electric motor
