The Mitsubishi CP30-BA1P21M3A is a 1-pole 3A circuit protector from the CP30-BA series, designed for protecting low-capacity control circuits. Rated for 250VAC / 65VDC with 2.5kA breaking capacity, it features M-type (Medium) thermal-magnetic trip characteristics in a 17.5mm wide DIN-rail housing. Applications include control transformer protection, solenoid valve circuits, relay coil protection, PLC I/O power supply protection, sensor and instrumentation circuits, and general industrial control panel auxiliary circuit protection.
**Q: What is the difference between CP30-BA1P21M2A and M3A?**
A: The only difference is the rated current — 2A vs 3A. Both are 1-pole, M-type medium trip characteristic. Physical dimensions and mounting are identical.
**Q: Why use a 3A circuit protector vs a standard 3A MCB?**
A: CP30-BA circuit protectors are UL1077 listed as supplementary protectors with tighter trip tolerances optimized for control circuits. Standard MCBs (UL489) are designed for branch circuit protection and may not provide adequate protection sensitivity for delicate electronic control circuits.
**Q: Can this protector be used for DC circuits?**
A: Yes, rated for DC circuits up to 65VDC (1-pole). For higher DC voltages, use a 2-pole model with poles connected in series (rated up to 125VDC).
