CoolMaster - BACnet Virtual addresses configuration

This article applies to the following CoolMaster products:

  • CoolMaster
  • CoolMasterPro 
  • CoolMasterNet

VA's -Virtual Addresses are used by CoolAutomation devices in order to simplify translation of the Indoor Unit number - UID into Instance Number of the BACnet Object Identifier.


UID is a string in format Ln.XYY. For Example:

L1.102 - Indoor Unit 102 on line L1

L2.003 - Indoor Unit 003 on line L2

List of UID's detected (visible) by CoolAutomation device can be retrieved with ls command.

L1.100 ON 19C 30C High Fan OK # 0
L1.101 OFF 28C 23C High Cool OK - 0


Each UID can have none, one or a number of associated VA's. VA's are plain numbers starting from 1. Device can automatically allocate and associate VA's with existing (visible by ls command) UID's:

>va auto 

To query allocated VA's use va command without parameters:

L1.100 --> 0001 [Hex: 0x0011 | Dec: 00017]
L1.101 --> 0002 [Hex: 0x0021 | Dec: 00033]

In example above UID L1.100 has a VA=0001 and UID L1.101 has a VA=0002. Numbers is '[' ']' braces are not applicable for BACnet modules (they are used for Modbus modules).

VA's can be allocated or deallocated (deleted) all together or separately. As shown above for automatic VA's allocation va auto command is used. It is possible to allocate VA for specific UID. For example, allocate VA 0004 for UID L1.102:

>va + L1.102 0004 

In this case UID does not have to be detected (visible) by CoolAutomation device at the VA allocation time. It is allowed to allocate a number of VA's for any given UID.

To delete all allocated VA's:

>va delall 

Specific VA can also be deleted (below command will delete VA 0004):

>va - 0004 

Alternatively all VA's associated with specific UID can be deleted (below command will delete all VA's associated with UID L1.102):

>va - L1.102 

Once VA's are allocated BACnet MS/TP and/or BACnet IP can be used to access Indoor Unit parameters. Translation of the VA into Instance Number of the BACnet Object Identifier is made according to the scheme below:

Object Identifier bits
31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
Type Instance Number
VA Index


Was this article helpful?
0 out of 1 found this helpful