Westaflex WAC Binding

DEUTSCHE Version

Table of Contents Pre-requisites Binding configuration Item Binding Configuration Examples Troubleshooting

Pre-requisites

Our WAC Usage documention describes the protocol in detail and is the starting point for understanding everything else. It contains the fundamental ModBus knowledge you need in order to adapt successfully with our Binding. With this foundation in place, you will be ready to apply the ModBus network rules, so that your home appliances can interoperate with those produced by other manufacturers as part of the OpenHAB ecosystem. This will free consumers to choose the devices that best match their needs, and combine them in novel ways with other compatible devices. See below for guidance as to what to look out for in each section. The possibilities are endless.

Binding configuration

A key feature of ModBus that distinguishes it from other protocols is that any given node in the network can act as the master for one channel, and as the slave for another channel.  This allows complex network topologies to be formed.

Item Binding Configuration

This section describes how the host (MCU, PC interface etc) can interface with the WAC chip. Extended messaging is also introduced, which is useful if you need to include additional information such as the Device Number. Note that extended messaging does not extend the size of the data payload, which is fixed at 8 bytes and cannot be altered.

Name	Modbus function	Data address	Values
Heat	01h_Read_Coils	0	1-active, 0-passive
	Plate heat exchanger frost protection function
Fire	01h_Read_Coils	1	1-active, 0-passive
	Fire alarm
Filter	01h_Read_Coils	2	1-active, 0-passive
	Dirty filter alarm
Fan	01h_Read_Coils	3	1-active, 0-passive
	Fans alarm
LowPower	01h_Read_Coils	5	1-active, 0-passive
	Low voltage
Textract	01h_Read_Coils	6	1-active, 0-passive
	Temperature sensor alarm
Texhaust	01h_Read_Coils	7	1-active, 0-passive
	Exhaust air temperature sensor alarm
Timit	01h_Read_Coils	8	1-active, 0-passive
	Supply air temperature sensor alarm
RH	01h_Read_Coils	9	1-active, 0-passive
	DTJ(100) humidity sensor alarm (controller works in determining the moisture content of 70%)
ReturnWater	01h_Read_Coils	10	1-active, 0-passive
	Return water temperature sensor alarm
ToutDoor	01h_Read_Coils	11	1-active, 0-passive
	Outside air temperature sensor alarm (controller continues to work in determing ToutDoor less than zero degree)
MotorActive	01h_Read_Coils	12	1-active, 0-passive
	Fans ON
InDumpper	04h_Read_Input	13	0-90
	Outside air damper actuator
Preheater	01h_Read_Coils	14	1-active, 0-passive
	Preheater indication
Heater	01h_Read_Coils	15	1-active, 0-passive
	Heater indication
Speed	06h_Write_Holding_Register	16	0, 1, 2, 3
	Fans speed setting
TsetPoint	06h_Write_Holding_Register	17	0-30
	Supply air temperature set
RH_value	04h_Read_Input	18	0-99
	DTJ(100) humidity sensor value
Motor1	04h_Read_Input	19	0-3
	Motor 1 fan speed value
Motor2	04h_Read_Input	20	0-3
	Motor 2 fan speed value
Tlimit	04h_Read_Input	21	Hex: E0
	Supply air temperature value
Texhaust	04h_Read_Input	22	Hex: E0
	DTJ(100) temperature sensor value
Textract	04h_Read_Input	23	Hex: E0
	Exhaust air temperature sensor value
ToutDoor	04h_Read_Input	24	Hex: FFEC
	Outside air temperature sensor value
Twater	04h_Read_Input	25	Hex: FFEC
	Return water temperature value

Examples

to handle many slaves in RTU mode, non blocking connections and RTS flow control.....

modbus_t *mb;

  uint16_t tab_reg[32];

  mb = modbus_new_tcp("127.0.0.1", 1502);
  modbus_connect(mb);

  /* Read 5 registers from the address 0 */
  modbus_read_registers(mb, 0, 5, tab_reg);

  modbus_close(mb);
  modbus_free(mb);

See Examples of typical WAC Bindings, if you have any suggestions or questions don't hesitate to contact us or use our Github account. The snapshot version of our industry4.0 binding can be downloaded, together with the rest of openhab.

Troubleshooting

Congratulations! You should now have a good general understanding of how the WAC ModBus protocol works, which will give you a strong foundation for all the work you do with OpenHAB. Be Inspired →by our genuine Apps...