Midea MGA-D30W/SN1, Manual

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MCAC-2008-11 Air-cooled Modular Chiller
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Fix LCD at fore panel from rear side of the panel by screw driver. You must insure that the installing site of
gasket is correct; torque is 0.5Nm or less, if not, screen would be damaged.
Electrical installation
LCD electrical interface composed by a power supply interface and three Serial Communications ports.
Electrical wiring illustration as follows:
Power supply as DC24V; the 2pin plug seat, positive pole in left and negative one in right. Please be strictly
differentiating these two poles.
Three sets of DB9 pin serial ports, which are COM0, COM1, and COM2. COM0, the communication port of
RS232, which is the special serial port for uploading or downloading programs between LCD and PC; COM1
and COM2 are ports that integrated by RS485 and RS422, which communication protocol could be selected
by the code switch at the rear of LCD. We employ RS485 communication protocol and set unit communicate
via the port of COM2, therefore, COM2 switch codes shall be set as below:
Serial protocol The 1 bit The 2 bit The 3 bit The 4 bit
RS 485 ON OFF OFF OFF
When wiring, please connect the 8 foot of COM2 plug seat to “P ”port locating at the communication terminal