User Setup
The system defaults to Active Power as the output mode. The selection between Pa, P1, and Pt
is determined by the user setting on page 2 of the User Preferences menu.
The default Kh of the system is 10 micro-units per pulse. Hence the default output is 10
μWh per
pulse. The Kh can be changed on page 3 of the User Preferences dialog. The range of possible
Kh values is 5 micro-units to 65535 micro-units. Using 10 micro-units per pulse gives the same
Kh as most commonly available standards.
Pulse Generation
Power quantities are defined over a single cycle of the measured cycle. While instantaneous
power may vary from positive to negative over a cycle, the pulse output is designed to be
proportional to the net power over a cycle. To analyze the net power over a cycle we cannot
know the result until the cycle is completed.
Trace Description
Magenta
Phase A
Yellow
Zero Crossing Signal
Blue
Output Pulses
When operating in Time Domain measurement mode (a power computation every cycle), the
PowerMaster
®
computes the result for one cycle (for example the cycle designated by the vertical
cursors above) and outputs the associated pulses starting approximately 5 ms later. The pulses
have a constant frequency of 1.2288 MHz. The number of pulses in the burst is equal to the
measured value for the previous cycle divided by Kh. Any fractional remainder is carried over to
the next cycle.
Start of pulse burst.
Rev 1.5
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