GELLER
Labs Voltage Standards Catalog
Welcome to a catalog of voltage standards and transfer references currently available from GELLER
engineering. We offer basic reference boards as both assembled and calibrated
printed circuit boards and as boxed standards. The high stability
model is only sold as a boxed unit because the ovenized reference diode
is susceptible to room air currents. Delivery ranges from off the shelf
to two weeks, depending on current stock. All references come with a certificate of calibration that is NIST traceable through our Fluke 732B primary laboratory standard.
The SVR transfer reference provides a cost effective tool for
calibrating with long integrating times of 10 power line cycles (166.7 ms)
or greater. For faster gate times and to calibrate digitizing converters,
consider our lower noise LNVR-01HS high stability boxed reference.
The temperature coefficient, or "tempco",
is a measure of how much the output voltage can change in voltage with
changes in ambient temperature. Most manufacturers specify tempco in parts per million (ppm) per degree C. Since this is a fractional representation, the actual change in voltage per degree C is a function of the reference voltage. For example, a millionth of 10 V is 10 uV therefore 1 ppm / degree C is the same as 10 uV / degree C for a 10 V reference. Standards with the 01HS high stability
option (U.S. Patent No. 7,382,179) have the lowest tempcos.
All "L" grade and better reference boards and boxes are calibrated to within +/- 10 uV absolute and guaranteed to remain longer term (6 months) within +/- 500 uV (+/- .005%) of absolute as rated. Extra trim resistors are added to narrow the trim range for easier calibration. Calibration data is reported to 10 uV resolution (.0001%). The last digit of resolution will only be useful in the short term at the reported temperature and at the specified power supply voltage (15V for 10V references). Under these conditions, it is possible to obtain short term transfer accuracy of better than +/- .0005% absolute (+/- 5 ppm).
Any of our reference products can be re-calibrated on request for $10 plus shipping ($4.75 for priority mail). A six month calibration interval is recommended for all models. This item applies only to our products, we are not able to calibrate other items.
Our Low Cost Voltage Transfer Project for Amateur Scientists, Electronics Hobbyists, and Schools, is Supported in Part by Analog Devices Incorporated. Please visit the Analog Devices website!