ATK-M1 moulded-case circuit breakers

ATK-M1 uses several frame sizes and L / M / H breaking-capacity variants. Choose the working current for the cable and load, then check the available voltage, poles, Icu and Ics in the same model row. A frame size is not the operating current of every device within it. For example, the listed 63L is 3-pole, while 63M includes 3- and 4-pole options; these options cannot be transferred between variants.

Distribution feeders and motor circuits have different overload and starting-current behaviour. Select the applicable trip configuration and coordinate it with cable capacity, motor starting and downstream protection. A rating suitable for a steady distribution load cannot simply be reused for a motor with a high starting current. Record the complete model and trip configuration with the circuit design so replacements preserve the protection function.

Use the dimensions for the selected frame and pole count when reserving cabinet space. Include terminal access, accessories and operating clearance rather than checking body width alone. Apply the corresponding temperature-correction data to the real cabinet environment and verify sustained load together with cable capacity. Dimensions and correction factors from another frame should not be substituted merely because its model name belongs to the same series.