Advise on Drawing: Get Expert Opinion

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The discussion focuses on the differences between overload and short circuit protection in motor systems. Overload conditions occur when the motor experiences excessive load, typically triggering an overload relay after a set duration, such as 60 seconds at 150% of full load. In contrast, short circuits are immediate faults that activate a miniature circuit breaker (MCB) designed to trip quickly, usually within 0.1 to 0.5 seconds, at 5 to 10 times the full load current. Both devices serve distinct protective functions for electrical systems. The thread concludes with a suggestion to research "Coordinated Motor Protection" for further understanding.
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Please See the drawing and Advise...
 

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Overload - is just that - too much load on the motor, this is typically a long time ( relative to Short circuit issues) the OL Relay is configured for this case,, e.g. 150% of full load for 60 Seconds - etc.

A short circuit - is a fault, and the MCB is set up to protect for these cases, for example 5 to 10 x the Full load current, and this typically will trip in short ( 0.1 to 0.5 Sec after the Current is detected) or Instantaneous (as soon as the current is detected) -

The two device are protection for different types of problems.

Google Coordinated Motor Protection - that will probably be helpful.
 
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