What identifies field-wiring terminals on a refrigeration wiring diagram?

Field-wiring terminals on a refrigeration wiring diagram are typically identified by letters. This convention allows for clear and consistent labeling that corresponds with standard practices in the industry. Using letters helps to avoid ambiguity that might arise from the use of numbers, shapes, or colors, which can vary widely between different systems or manufacturers.

Each letter corresponds to a specific function or type of connection in the circuit, such as power, ground, or control signals. This systematic approach simplifies tracing wiring paths, troubleshooting, and ensuring correct connections when installing or servicing refrigeration equipment. The clarity provided by letter identification is especially helpful in complex wiring diagrams, where multiple connections might be involved.