Page 7 - Voltech Instruments PM3000A Universal Power Analyser, designed and produced by Connell Marketing Associates, UK

Set Up

The set up keys control the configuration of the analog circuitry of the PM3000A. This
enables the PM3000A to be used in a wide variety of specialized applications.

FREQ FREQ SOURCE.
SOURCE
The measurements made by the PM3000A are synchronized to the ac
INT supply frequency.
EXT
INT mode synchronizes measurements to input voltage or current,
over the frequency range 5Hz to 1MHz. The user can choose voltage
or current for frequency measurement, which is helpful in applications
such as motor drives, where one input may be 'chopped'.

EXT mode synchronizes measurements to a signal applied to a rear
panel connector. It is used when both voltage and current are
'chopped', or for frequencies down to 0.1Hz.

VOLTS VOLTS AMPS.
AMPS
RMS This mode is normally selected whereby the PM3000A displays
RMS voltage and current measurements as true rms.
MEAN
MEAN Voltage and current measurements will be displayed in terms
of their rectified mean value. This is useful in electrochemical
applications and for calibrating mean sensing instruments.

AVG AVG.

AUTO The PM3000A will average a number of measurements to display a
N steady reading despite fluctuations at the inputs.

AUTO In this mode the instrument will average 16 measurements;
any substantial change in input conditions will automatically cancel
averaging to give a fast reponse.

N In this mode the user can force the PM3000A to average up to 64
measurements in order to provide a steady reading even when large
changes in input conditions are occuring.

COUP COUPLING
- LING
AC + DC is normally selected. The PM3000 will compute results due
to all components in the input voltage and current waveforms, including

AC+DC the dc and low frequency components.

AC configures the instrument to ac couple the input signals. This is
AC useful for examining ripple voltage on rectifier outputs and for the

calibration of other instruments that are ac coupled.

SHUNT SHUNT

INT INT mode is selected for direct measurements of ac and dc currents
EXT up to 30A rms, and uses signals from precision internal shunts in the
PM3000A. This mode is also used with AC current transformers.

EXT mode is used when taking current measurements with external
high current shunts, DC current transformers, or other devices providing
a voltage signal that is proportional to current.

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