DC Solid State Relay Board: This is a opto-Transistor with optical isolation between input signal and output signal. This is to be used for switching 5V-100VDC, 5060Hz supply by 5V-230 VDC input signal. Features DIN rail mountable EightFour DC SSRs on a single board Sink or Source input selection by jumper selection LED indication for input signal Semiconductor Fuse protection for short circuit and overcurrent Output points in two groups. Each group consists four op points