LG System Air Conditioner PI-485 communication driver

LG System Air Conditioner PI-485 communication driver is the driver to communicate with system air conditioner of LG Electronics in Korea.

Note) LG System Air Conditioner(Multi V compatible model) PI-485 communication driver can communicate with PI-485 at outdoor unit of air conditioner. ( refer to chapter 3 )

1. Read Settings

<Figure 1> is read setting example of LG System Air Conditioner PI-485 communication driver.

<Figure 1>  Read setting example of LG System Air Conditioner PI-485 communication driver

Device part of  <Figure 1> input Com Port(COM1), Baud Rate(4800), Parity Bit(0), Data Bit(8), Stop Bit(1) respectively, according to controller.

In protocol option part, you can set 'write retry count'( 1 ~ 20, default = 3 ), 'weather to use 16 room central controller for read code'(1 : use, 0 : don't use, default = 0), 'weather to use 16 room central controller for write code(1 : use, 0 : don't use, default = 0). Each argument  is a comma-delimited.

Note) Baud rate, Parity bit, Data bit, Stop bit of PI-485 are fixed to 4800, 0, 8, 1.

When you using with 16 room central controller, you have to set Slave mode( pin 2 = Off ).

LG System Air Conditioner PI-485 communication driver read schedule

Read schedule setting parameters are as follows:

1) Group/Station – 0 ~ 255 group, station number.

group = 0 ~ 15, station = 0 ~ 15. ( refer to <Table 1> )

2) Read command – Command = READ. ( read of current air conditioner status )

3) Read start address –  don't care.

4) Save start address for Communication Server – Saving start address of Communication Server.

5) Read Size – fixed to 1. ( refer to <Table 2> )

Read schedule example)

READ,     5,  READ,     0,    0,   1,

READ,     6,  READ,     0,   20,   1,

READ,     7,  READ,     0,   40,   1,

READ,     8,  READ,     0,   60,   1,

READ,     9,  READ,     0,   80,   1,

<Table 2> is data saving address and contents of LG System Air Conditioner PI-485 communication driver.

 If you click the icon  in protocol option part, you can see the dialog box such as <Figure 2>. you can also set read schedule by using this part.

<Figure 2> Example of LG System Air Conditioner PI-485 communication driver’s Option dialog box

You can set read schedule by using , ,  button and listbox of <Figure 2>.

Also, you can set set write retry count, weather to use 16 room central controller for read/write code by using the part of 'Write Retyr', 'Use Simple( 16 Room ) Central Controller' shown in <Figure 2>.

<Figure 3> Example of LG System Air Conditioner PI-485 communication driver’s read schedule Add/Edit dialog box

When you click Add button or Edit button in dialogue box of <Figure 2>, dialogue box of <Figure 3> will be shown.

2. Writing settings

 You can control LG System Air Conditioner by using 'writing settings'. 

Note) LG System Air Conditioner PI-485 communication is good to set 3 or more 'Write Retry' count to write the correct

Digital Write

Digital write and analog write have the same setting parameters except output value. 

Analog Write 

Analog write setting parameters are as follows:

1)  PORT                   Port no. (0 ~ 255)

2)  STATION             0 ~ 255 group, station number.( refer to <Table 1> )

3)  ADDRESS          don't care.

4)  Extra1                  Write command.

RUN : On, Off control,

LOCK : Lock set/release command,

PLASMA : Plasma set/release command,

MODE : run mode setting, 0 = cooling, 1 = dehumidification, 2 = ventilation, 3 = artificial intelligence, 4 = heating,

DIR : wind direction setting, 0 = fixed, 1 = rotation,

WIND : quantity of wind setting, 1 = mild, 2 = middle, 3 = high, 4 = auto,

TEMP : setting temperature command, 18 ~ 30℃(Celsius). 

5) Extra2                   don't care.

Write example 1)

PORT:0,  station:6, ADDRESS:0000, Extra1: RUN,  Extra2 : 0

The setting parameter shown above is On(1), Off(0) control example of 0 group, 6 station LG System Air Conditioner.

Write example 2)

PORT:0,  station:6, ADDRESS:0000, Extra1: MODE,  Extra2 : 0

The setting parameter shown above is run mode setting example of 0 group, 6 station LG System Air Conditioner. ( 0 = cooling, 1 = dehumidification, 2 = ventilation, 3 = artificial intelligence, 4 = heating )

Write example 3)

PORT:0,  station:6, ADDRESS:0000, Extra1: DIR,  Extra2 : 0

The setting parameter shown above is wind direction setting example of 0 group, 6 station LG System Air Conditioner. ( 0 = fixed, 1 = rotation )

Write example 4)

PORT:0,  station:6, ADDRESS:0000, Extra1: WIND,  Extra2 : 0

The setting parameter shown above is quantity of wind setting example of 0 group, 6 station LG System Air Conditioner. ( 1 = mild, 2 = middle, 3 = high, 4 = auto )

Write example 5)

PORT:0,  station:6, ADDRESS:0000, Extra1: TEMP,  Extra2 : 0

The setting parameter shown above is quantity of setting temperature writing example of 0 group, 6 station LG System Air Conditioner. ( 18 ~ 30℃ )

3. Equipment connection for PI-485 communication

Equipment connection for PI-485 communication are as follows.

Install of PI-485 communication card

Please install  PI-485 communicaton card at outdoor unit of air conditioner such as <Figure 4>.

DIP switch setting of PI-485, (new version of PI 485 have 8 pin, but normally pin 5 ~ 8 = OFF )

MULTI V(except LRA) & MPS inverter multi equipment + old central controller = ON only pin 1,

MULTI V(except LRA) & MPS inverter multi equipment + LGAP(LG Air-con Protocol) central controller = pin 1, 4 = ON, (generally)

MPS constant speed multi equipment + old central controller = ON only pin 2,

MPS constant speed multi equipment + LGAP central controller = pin 2, 4 = ON,

MULTI V LRA equipment + LGAP central controller = pin 1, 2, 3, 4 = ON.

<Figure 4> Example of PI-485 communication card at outdoor unit

Install of PI-485 to RS-232C converter at computer

Please connect PI-485 to RS-232C(CS-428 i model of System Base, ...) converter at computer such as <Figure 5>.

<Figure 5> Example of PI-485 to RS-232C(CS-428 i model of System Base) converter

Connection of PI-485 communication cable

Please connect BUS A, B connector of PI-485 and +, - connector of computer.

             PI-485                              computer

               BUS A  -----------------------  +

               BUS B  -----------------------  -

4. 16 room central controller

<Figure 6> is example of 16 room central controller.

<Figure 6> Example of 16 room central controller