Is COM wire the same as Neutral wire in AC?

Question

I am reading about a thermographic camera installation and I found in the schematic this diagram which has COM terminal and 24V, I have that physically and I was wondering if the COM terminal is the same as Neutral? (I underlined both terminals with yellow):

The physical installation consist of two cables (So the COM cable is the same as Neutral wire):

could you explain me why are not they the same? I can not figure out — imt_blake, Jan 14 '23 at 23:54
why don't you measure the continuity between neutral and COM? — jsotola, Jan 15 '23 at 00:23

score 2 · Accepted Answer · answered Jan 15 '23 at 00:02

Not the same as the neutral wire, the neutral wire is for connection to the mains, the common wire is internal to the AC (HVAC) system.

However they serve a similar purpose. and there are many parallels that can be drawn. so the "C" wire is not Neutral, it's just like neutral.

Typically the C wire is connected to ground inside the AC. The R wire is the AC's 24V "live" equivalent.

The C wite is needed for wifi thermostats like the neutral is needed for wifi lightswitches,

Is COM wire the same as Neutral wire in AC?

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