Orion System BACnet Link - Manual (Page 12)

Technical Guide
BACnet ® Link Interface 12
Programming - Standard Objects
Parameter Instance Numbers
Instance Number Calculation
The Instance Number for a controller parameter is determined by using
the BACnet
® Link Loop Address for the controller, the MUA II, VAV/
CAV or CW/HW controllers address switch setting and the Instance
Number Base of the desired Parameter you wish to calculate for that
controller..
In order to calculate the Instance Number for the desired Parameter you
must use the WattMaster base address (600191) as a starting point.
Next you must determine the BACnet ® Link Loop Address for the con-
troller you wish to calculate. This is determined by looking at the BAC-
net
® Link Loop Address switch setting for the loop the desired control-
ler is installed on. See Figure 3 for Loop Address switch setting infor-
mation. Be sure to use the BACnet ® Link Loop Address not the “MAC”
address. Possible valid BACnet ® Link Loop Address addresses are 0
through 3.
Proceed by determining the address switch setting of the controller you
wish to calculate. This is accomplished by verifying the address switch
setting for the desired controller. Possible valid controller addresses are
1 through 32.
Look up the Instance Number Base for the controller and specific pa-
rameter you desire from the Instance Number Base Table for that con-
troller. See Table 3 through Table 5.
Use the numbers that you just determined to calculate the Instance Num-
ber for the desired parameter using the formula below. Please see the
examples that follow the formula.
Table 6: Parameter Instance Number Calculations
P aram eter Instance N um ber C alculatio n E xam ples
Co ntroller
T ype &
P aram eter
B AC net
Link
Loo p
Ad dress
Co ntroller
Ad dress
Param eter
Instance
Num b er
B ase
P aram eter Instance N um ber
Calculatio n
P aram eter
Instance
Num b er
M UA II
C urrent M od e
0 1 11 600191 +((0 * 16 + 1-1) * 64) + 11) = 600202 600202
M UA II
A larm Status
3 3 14 600191 + ((3 * 16 + 3-1) * 64 ) + 14) = 603405 603405
VAV /C A V
C ontrol M od e
1 14 11 600191 + ((1 * 16 + 14-1) * 64 ) + 11) = 602058 602058
VAV /C A V
A larm Status
2 15 17 600191 + ((2 * 16 + 15-1) * 64 ) + 17) = 603125 603125