X1
A standard controller for simple applications
Heat / Cool temperature controller
1/8 DIN - 48x96 mm 
   - 4 relay outputs
   - Start up function
   - Current transformer input
   - Timer

X3
The multifunction controller
Double action controller with analogue output
1/8 DIN - 48x96 mm 
   - Heat - Cool
   - Valve drive output
   - Auto/Manual

X5
Sophisticated multifunction process controller with high level   communication
Process controller with PROFIBUS DP and Modbus/Jbus   Master/Slave
1/8 DIN - 48x96 mm 
   - Update time: 50 ms
   - Frequency input
   - 2 analogue outputs
   - Setpoint programmer
   - Memory Chip