You're right to be confused! Mike Holt's explanation of A1 and A2 markings isn't quite accurate or consistent with how they are typically used and understood in the electrical industry.Here's a more accurate breakdown of how A1 and A2 (and other "A" designations) are typically used when referring to terminals and wiring, specifically in the context of control panels and schematics: General Purpose

A1, A2, etc., are typically used as a common way to designate general power inputs. Usually A1 and A2 are used for 120VAC.

Control Power

The "A" designation is commonly used for control power. Therefore A1, A2 are likely the control power inputs.It's important to note:

No Universal Standard

While the above is common, there's no legally binding standard requiring A1, A2, etc., to always mean the same thing. It's crucial to

refer to the specific equipment's documentation (schematics, wiring diagrams, etc.) to understand what those designations represent in that particular situation. The manufacturer's documentation overrides any general conventions. Importance of Documentation: Always rely on the equipment manufacturer's documentation to determine the actual meaning of any terminal markings (A1, A2, X1, X2, T1, T2, L1, L2, etc.). Don't assume their function.Therefore, your understanding that Mike Holt's explanation is not fully accurate is correct. Focus on understanding the specific context and documentation for the equipment you are working with. Flag for review