WHAT IS : CMH008 is the expansion module for CMH088 boards. Each CMH088 recognize up to 2 expanders. There are two kinds of CMH008 :

1) Balanced : upgrade the system with 8 double balanced

2) Analogic : upgrade the system with 8 inputs that reads the value in d.d.p (0/5Volts) or in current (0-20mA) in input