When connecting a 3-phase air handler unit, is it necessary to install an Equipment Grounding Conductor with Flexible Metal Conduit?

When connecting a 3-phase air handler unit, it is indeed necessary to install an Equipment Grounding Conductor (EGC) with Flexible Metal Conduit (FMC). This requirement is based on the National Electrical Code (NEC), which mandates that any electrical installation should include grounding to ensure safety and compliance with electrical standards.

The installation of an EGC provides a low-resistance path for fault currents, which is crucial for protecting both people and equipment from the dangers of electric shock and potential fire hazards that can result from electrical faults. The use of FMC inherently includes grounding properties; however, it is still required to install an EGC to maintain proper grounding practices and enhance the overall safety of the system.

Additionally, grounding protects sensitive equipment from voltage spikes and electrical noise, which can be common in 3-phase systems. Failure to include an EGC could lead to non-compliance with electrical code requirements and compromise the safety and functionality of the air handler unit. Overall, ensuring proper grounding is a critical aspect of designing and executing electrical installations.