Square D 800 Amp Type M Circuit Breaker Trip Unit 3 Pole

Square D 800 Amp Type M Circuit Breaker Trip Unit 3 Pole

The 800A magnetic trip feature in Square D breakers is an essential aspect of their functionality. Let’s delve into the details:

1. Purpose: The magnetic trip function provides instantaneous protection by rapidly opening the circuit when a high current surge (such as an inrush current) occurs. It prevents damage to equipment and ensures safety.

2. Adjustment Slider: The breaker you’re working with has an adjustment slider marked with “min” and “max.” Here’s what it means:

   • Min Setting: This corresponds to the minimum magnetic trip level. In other words, it determines how sensitive the breaker is to sudden current spikes.
   • Max Setting: This represents the maximum magnetic trip level. Setting it higher allows the breaker to tolerate larger inrush currents before tripping.

3. Typical Use Cases:

   • Inrush Currents: Adjusting the magnetic trip level allows you to accommodate inrush currents during motor startup or other transient events.
   • Downstream Coordination: Coordinating with downstream devices (such as fuses or other breakers) ensures proper protection and prevents nuisance tripping.

4. Recommendation:

   • Leave It at the Minimum: Unless you have a compelling reason to do otherwise, it’s advisable to keep the magnetic trip slider set at the minimum. This minimizes the risk of arc flash incidents by ensuring faster tripping.

Remember, this adjustment is crucial for maintaining the balance between protection and operational efficiency.