On the YL600 VFD which connections are DCM, ACM, V1 & Forward?

The DCM is DC common, or DC Ground which is used in conjunction with Forward (FWD, or FOR) to start the spindle in the forward direction. The ACM is the AC Common, or AC Ground (Alternating current, or in this case, a variable voltage for spindle speed). The ACM is used in conjunction with V1 to provide variable speed for the spindle. In order to use the terminals DCM/XGND, FOR/FWD, ACM/GND and V1/VI1, you will need to program the VFD to enable the terminals and disable the control panel. YL-600: Start/Stop - XGND or COM is paired with FWD or X4 (X5 for Reverse). Spindle Frequency: XGND or COM is paired with AI1 and uses a top end of 5VDC YL-620: Start/Stop - XGND is paired with FWD (REV for reverse) Spindle Frequency: GND (not XGND) and VI1. The Start/Stop portion of the control panel and terminals is separate from the spindle speed/frequency control panel and terminals. Each of these have a separate programming parameter. For the YL-600/620, the P00.01 parameter controls the source of the start/stop function. Settings for the P00.01 are: 0: Control Panel is used and the terminals are disabled. 1: Terminals are enabled and the Stop on the control panel is still enabled if needed. 2: Terminals are enabled and the Stop on the control panel is disabled. 3: Control is sourced from the MODBUS also specified as the RS-485 connection. This would be labeled as RX and TX (Receive and transmit) and uses the UART protocol (serial communication protocol). https://buildyourcnc.com/FAQ/13381 explains this in depth. Additional Information: DCM is Digital Common, ACM is Analog Common