Appendices
Appendix J - Core Measurement Parameters: Power Factor
113
Building Technologies
125-202
06/06/2017
Measurement Parameters: Power
BACnet
Object
Identifier
Modbus
Register
Modbus
Offset
(Offset to a
Base of 40001)
If kVA L2 value>0, positive kVA L2 = total kVA L2, negative kVA L2 = 0
If kVA L2 value<0, negative kVA L2 = total kVA L2, positive kVA L2 = 0
Individual Phase Apparent Power- L3 (kVA L3)
= total kVA L3 value, signed, individual L3 phase true power in kVA, BACnet
= total kVA L3 value, unsigned, individual L2 phase true power, in kVA
= positive kVA L3 value, unsigned, individual L2 phase true power, in kVA
= negative kVA L3 value, unsigned, individual L2 phase true power, in kVA
NOTES:
If kVA L3 value>0, positive kVA L3 = total kVA L3, negative kVA L3 = 0
If kVA L3 value<0, negative kVA L3 = total kVA L3, positive kVA L3 = 0
8030
‒
‒
‒
‒
44049
46049
47047
‒
4048
6048
7048
Measurement Parameters: Power
BACnet
Object
Identifier
Modbus
Register
Modbus
Offset
(Offset to a
Base of 40001)
kVAR – Reactive Power defined as Kilo Volt-Amperes, Reactive
is a measure of the rate of power that is sloshing back and forth, twice a cycle, between an AC source and a reactive (capacitive or inductive)
load.
System Maximum Instantaneous Reactive Power Demand
(kVAR Demand System Max) - resettable
returns maximum demand value read since startup or reset of demand register
= kVAR Dmd max, unsigned, absolute, kVAR demand, in kVAR, BACnet
= kVAR Dmd max value, unsigned, absolute, kVAR demand, in kVAR
= positive kVAR Dmd max, unsigned, positive value, kVAR demand, in kVAR
= negative kVAR Dmd max, unsigned, neg. value, kVAR demand, in kVAR
NOTES:
If Dmd value>0, Dmd positive = Dmd value, Dmd negative = 0
If Dmd value<0, Dmd negative = Dmd value, Dmd positive = 0
5120
‒
‒
‒
‒
44084
46084
47084
‒
4083
6083
7083
System Average Reactive Power Demand
(kVAR Demand System Now) - resettable
returns new value every minute, will compare and post to min/max registers
= kVAR Dmd now, unsigned, abs, most recent dmd window, in kVAR, BACnet
5130
‒
‒
System Total Reactive Power (kVAR System)
= unsigned value of ABS(kVAR L1)+ABS(kVAR L2)+ABS(kVAR L3), in kVAR
= kVAR Sys, signed, absolute, in kW, BACnet
= kVAR Sys value, unsigned, total instantaneous true power, in kVAR
= positive kVAR Sys, unsigned, positive instantaneous true power, in kVAR
= negative kVAR Sys, unsigned, negative instantaneous true power, in kVAR
NOTES:
If kVAR value>0, kVAR positive = kVAR sys, kVAR negative = 0
If kVAR value<0, kVAR negative = kVAR sys, kVAR positive = 0
5000
‒
‒
‒
‒
44010
46010
47010
‒
4009
6009
7009
System Net Total Reactive Power (kVAR System Net)
= signed net value of ABS(kVAR L1)+ABS(kVAR L2)+ABS(kVAR L3), in kVAR
= kVAR SysNet, signed, absolute, in kW, BACnet
5001
‒
‒
Individual Phase Reactive Power- L1 (kVAR L1)
= total kVAR L1 value, signed, individual L1 kVAR power in kVAR, BACnet
= total kVAR L1 value, unsigned, individual L2 kVAR power, in kVAR
= positive kVAR L1 value, unsigned, individual L2 kVAR power, in kVAR
= negative kVAR L1 value, unsigned, individual L2 kVAR power, in kVAR
NOTES:
5030
‒
‒
‒
‒
44038
46038
47038
‒
4037
6037
7037