Chapter 6 Control Terminals CFP2000 When the photo-coupler is using internal power supply, the switch connection for Sink and Source as below: MI-DCM: Sink mode MI-+24V: Source mode When the photo-coupler is using external power supply, please remove the short circuit cable between the +24V and COM terminals. The connection mode is Sink mode or Source mode according to the below: The “+” of 24V connecting to COM: Sink mode The “-“ of 24V connecting to COM: Source mode 6-3