Model 1600A transfer standard
3. The Model 1600A Autobalance AC/DC Transfer Standard (ATS)(fig 3-1) is designed
to permit a semi-skilled operator to make rapid and precise true RMS measurements
of AC voltages with a minimum of operator participation, thereby reducing the
possibility of human error.
The ATS also has the ability to provide manual
transfer and balancing measurements (i.e., orthodox AC/DC transfer standard
The applied signal under measurement is attenuated and applied to a
thermoelement which produces a DC voltage proportional to the heating (RMS) value
of the signal. An internally generated DC voltage having the same heating value is
then substituted for the applied signal and this DC voltage is coupled to auxiliary
readout instrumentation to provide a true RMS equivalent of the applied signal.
The manual transfer mode of operation allows the operator to initiate the point in
time at which the AC to DC transfer occurs and, in some instances, allows more
accurate measurements than is possible in the automatic mode. The manual balance
mode requires the operator to manually balance the unit and, while being somewhat
more time-consuming, it is still a rapid operation and permits highest accuracy
measurements down to 2 Hz.
a. The ATS is a semiautomatic AC/DC transfer standard which provides a DC
output voltage equal to the true RMS value of complex (i.e., pulsed, square-wave,
triangular-wave and other nonsinusoidal signals having crest factors of up to 10:1)
or sinusoidal signals. The DC output voltage generated is applied to an auxiliary
readout instrument, such as a DC differential or DC digital voltmeter, which
indicates the DC RMS equivalent of the applied input voltage.