4-channel Isolated Digital Input and 4-channel Isolated Digital Output Module.The tM-P4C4 provides 4 channels for digital input and 4 channels for digital output, each of which features photocouple isolation. The tM-P4C4 supports sink-type output with short circuit protection, while input is source-type. All input channels can be used an 16-bit counters. There are options for configuring power-on and safe digital output values. 4 kV ESD protectio..