The RD-22 Dytronic Primary Transfer Standard represents the state-of-the-art technology in a commercially available true DC to AC accuracy transfer reference. The RD-22 has typical AC measurement accuracies within the limits of traceability. Repeatability of 1 ppm can be attained at 120 V and 5 A inputs of specific models.
The RD-22 utilizes RADIAN’s Dytronic measurement technology featuring a Radian designed Integrating Analog to Digital Signal Converter based upon a charge-balance conversion principle. The RD-22 also employs a new Radian electronically compensated concentric core current comparator transformer.This current comparator is autoranging and external to the standard, allowing for non-galvanic current connection to the unit. These two new technologies combine with existing Radian features to provide the highest degree of accuracy, stability and versatility ever offered in a primary transfer standard.
The RD-22 can be used to transfer accurate and traceable measurements from Radian Research’s calibration laboratory. Alternatively, it can be calibrated directly by a National Metrology Laboratory, such as the National Institute of Standards and Technology (NIST).
The RD-22 can also be tested by using external DC primary reference sets of voltage, current, and time. These external DC references can be compared directly to the RD-22’s internal reference sets. Additionally, the RD-22 can be used as the active reference to the Radian RS-933 Laboratory Reference System to provide a complete AC electric metrology lab.
The RD-22 provides four quadrant, single-phase simultaneous energy and power measurements. The potential input and current input are totally autoranging. This autoranging feature was pioneered by Radian Research and makes it impossible to damage the unit by applying a signal to the wrong tap. The potential input range is 60 to 600 V, the current input range is 0.2 to 125 A or 0.2 to 200 A. The external auxiliary power input converter provides 24 V DC to the auxiliary power input of the RD-22. The external auxiliary power converter minimizes 60/50 Hz line frequency interference from coupling to the measurement circuitry.
The RD-22 can optionally analyze harmonic waveforms through the 150th harmonic order. A second option enables the RD-22 to automatically calculate and display the error of standards being tested. The analog sense option allows for testing of transducers and other devices that provide an analog current output instead of a digital pulse output. The RD-22 also provides a serial communications port for direct connection to the RS-232 serial port of a personal computer.
The RD-22 utilizes Radian’s Dytronic measurement technology featuring a Radian designed Integrating Analog to Digital Signal Converter based upon a charge balance conversion principle. The RD-22 also employs a Radian electronically compensated concentric core current comparator transformer.
The RD-22 can be used to transfer accurate and traceable measurements from Radian Research’s calibration laboratory. Alternatively, it can be calibrated directly by a national laboratory, such as National Institute of Standards and Technology.
When used with RS-933 Laboratory Reference System the RD-22 serves as an active reference to provide complete AC electric metrology.