Dimensions 32 x 74 mm are miniature temperature controls for medium temperature shutdown defrost refrigeration systems There are 1 compressor (refrigeration) output and 2 NTC or PTC probe inputs: one for the room temperature, The input of another temperature probe (P4) is optional. It needs to be specified when ordering. You can choose whether to Use, connect to terminals 2 and 4 (either left or right) of the 5-pin hotkey programming key interface (connector required, must be ordered separately, model: NG6-K), can be used to measure condensing temperature alarm or used to display the temperature at a point; the digital input can also be set up as a third temperature probe (P3) Input (use or not can be selected by parameter). The hot key programming interface can be connected to the programming key, and can also be connected to the XJ485-CX communication conversion module. Go to a network compatible with ModBUS-RTU protocol, such as DIXELL's XWEB series monitoring system.