Thermal Magnetic Circuit Breaker Symbol Iec. A thermal fuse is a temperature sensitive switch. 140m devices as self protected combination motor controller or a type e motor controller applicable under nec 430 52 c 6.
Electrical iec 60617 bs 3939 symbols representing isolators disconnectors fuses contactors and overloads for usage in drawing electrical circuits. As per iec 60898 2 electrical accessories circuit. Horizontal symbol vertical symbol description hcb1 vcb1 circuit breaker 1 pole hcb11th vcb11th thermal circuit breaker hcb11thi vcb11thi current limit thermal hcb11q9 vcb11q9 magneto thermal hcb11q13 vcb11q13 magneto thermal with differential hcb11q17 vcb11q17 differential hcb11q29 vcb11q29 with current protection hcb11q33 vcb11q33 with current protection and lack of voltage protection hcb11q37 vcb11q37 with max.
These clarifications aside the application issues for use with variable frequency drives do not change globally.
In american homes today thermal magnetic circuit breakers are the most common type. These are circuit breakers which utilize two components to detect electrical faults. Thermal and magnetic trip definition mcb uses an electromechanical trip unit to open the contacts during an overcurrent condition. It operates on the temperature rather than the current unless the current is sufficient to increase the temperature above the threshold point.
