Power Factor Sign Conventions - Siemens ACCESS 9340 Reference Manual

PMCM-9340D-0208
2/2008

Power Factor Sign Conventions

Figure 4–2: Power factor sign convention
Reactive
Power In
Quadrant
2
watts negative (–)
vars positive (+)
power factor (–)
Reverse
Power Flow
watts negative (–)
vars negative (–)
power factor (–)
Quadrant
3
IEC Power Factor Sign Convention
© 2008 Siemens Energy & Automation, Inc. All Rights Reserved.
An alternate power factor storage method is also available for use
with analog outputs and trending. See the footnotes in "Register List"
on page 122 for the applicable registers.
The meter can be set to one of two power factor sign conventions:
IEEE or IEC. The ACCESS 9340/9360 defaults to the IEEE power
factor sign convention. Figure 4–2 illustrates the two sign
conventions. For instructions on changing the power factor sign
convention, refer to "Advanced Meter Setup Options" on page 26.
Quadrant
1
watts positive (+)
vars positive (+)
power factor (+)
Normal
Power Flow
watts positive (+)
vars negative (–)
power factor (+)
Quadrant
4
Figure 4–3: Power Factor Display Example
!
"
#

Quadrant
2
watts negative (–)
vars positive (+)
power factor (+)
Reverse
Real
Power Flow
Power
In
watts negative (–)
vars negative (–)
power factor (–)
Quadrant
3
IEEE Power Factor Sign Convention
4QTD 0&
=
=
=
=
4/4!,
425% $)30,
ACCESS 9340 and 9360 Meters
Chapter 4—Metering Capabilities
Reactive
Power In
Quadrant
1
watts positive (+)
vars positive (+)
power factor (–)
Normal
Power Flow
watts positive (+)
vars negative (–)
power factor (+)
Quadrant
4
The power
factor sign is
visible next to
the power factor
reading.
Real
Power
In
EN–43