10 Volt 10 V DC Prec. Voltage Reference Standard, Nulled to Fluke 732A or 732B

Description

We are a manufacturer in the United States. The item for sale is
a
10.000000VDC Precision Voltage Reference/DC Standard. It accepts 12.0VDC to 35.0VDC INPUT. The OUTPUT is 10.000000 VDC ±0.0002% (±2ppm) at 14.5VDC (±0.1VDC) INPUT. The other unit we have listed is the 10.000000VDC ±
0.0006%
. The absolute accuracy and the price are the only differences between this unit and our novice product, the ±0.0006% voltage standard. The ±0.0002% 10VDC standard (the one in
this
description) has (4) four nonmagnetic, low thermal EMF, gold-flashed, color-coded banana-sockets w/binding posts for INPUT and OUTPUT connections. The internal connections are soldered or bolted. We highly recommend the same leads be used by end users as are used during the final calibration procedure. Those are available here:
https://www.ebay.com/itm/253405049160
.
The regulator IC is socketed for low hysteresis and to prevent heat damage to the IC by soldering. The main board is a low-hysteresis PCB design, which prevents output drift due to mechanical stresses on the regulator IC and other internal components. We integrate the reference IC , the REF102CP, with (2) low-pass filters for AC noise-suppression, shielding against induced thermoelectric effect, and temperature compensation.
The ±0.0002% standard can be power-cycled without affecting the absolute accuracy (±2ppm). Our testing indicates that under 100% up time at 10M Ohm load (think DMM), long-term drift is < 3.0ppm/120 days, < 7.0ppm/year. Drift in the powered down state is < 4.0ppm/year.
Theory of Operation:
DC input is fed to a capacitor configured with a die-embedded precision resistor within the regulator IC. This shorts out AC harmonic artifacts on the input side using a class 1
low-pass filter
. The regulator IC employs a laser-trimmed zener diode as a precision voltage regulator and input to noninverting (+) voltage feed to the on-die op amp. The op amp operates in voltage-feedback mode with the gain set by a voltage divider with an in-loop, precision external trimmer. The 6.7VDC produced by the zener reference is raised to an output that is within ±5.0mVDC (0.05%) of 10.0VDC. The op amp output is cleaned of high-frequency AC produced by the on-chip zener, by an output low-pass filter that employs an on-die resistor and an external capacitor. The resultant signal has a noise level of <=2uVp-p (0.2ppm), which is easily filtered by most bench DMMs. The gain of the on-die op amp is trimmed by a potentiometer selected for its performance over time and temperature.
During calibration the manual adjustment of the op amp gain (output) trim-pot while nulling the output to a Fluke 732A or 732B DC Standard, traceable to the United States Institute of Standards and Technology (NIST) and the Josephson Junction Array at Fluke Calibration in the USA , and then monitoring the calibration on a daily-calibrated Agilent 3458A 8-1/2 digit multimeter, results in unparalleled precision for an inexpensive DC Standard.
We purchase and evaluate similar products. Our customers: calibration labs, defense contractors, university research labs, technology consultants, system integrators, etc., often will purchase similar devices from our competitors, and ask us to test them and give a report. I have found not one that performs according to the claimed spec.
Secondly, the unit employs passive temperature compensation (TC) using a precision thermistor and heat-transfer coupling between the regulator IC and the TC thermistor. The heat-transfer coupler lowers the temperature
difference
over time, between the regulator IC and the TC thermistor, which is the same as saying it lowers the delta(deltaT/T) between the regulator IC and TC thermistor. The thermistor disciplines the output gain to change the device’s output voltage in an equal but opposite magnitude to the temperature drift of the raw regulator IC, which provides: (TdriftRegIC= ~+2ppm/℃) + (deltaVout=~(-)2ppm/℃)=0ppm temperature drift between 17℃ and 26℃ (64℉ and 80℉); 20%-55% RH.
But that is in an ideal world! In our situation the drift has been reduced to <=±2ppm over the range 17℃-26℃, which is 1/12 the
typical
temperature drift for the bare TI-REF102C.
The passive temperature compensation relies on the fact that the TC thermistor response is roughly linear over the range 17℃-26℃, negating the need for an onboard oven. This produces a total current draw of 1.5mA, making the unit usable with (2) 9V batteries wired in series (Duracell Procell or Energizer Industrial recommended).
This is a ±2ppm DC standard that fits in a pants or shirt pocket, weighs about 3 ounces (84 grams), maintains its calibration across power cycles, can be powered by a DC power supply (switching or linear, or even a wall-wart) OR inexpensive 9V batteries, and drifts < 3.0ppm/120 days. Ripple rejection is: 111:1, or 11,000%. The internal noise created by the device is: < 2uVp-p.
Among the photos is a laboratory null voltage-offset setup. See configuration data at the end of the listing.
The graphs pictured above are output voltage vs time. The graphs indirectly show temperature drift. All units are nulled to a characterized 732A or 732B DC standard. The ±0.0002% standard consumes roughly 15mW. From cold start the device settles in one-half hour. Warm cycling requires several seconds to five minutes to resettle. Maximum output load is 10.0 mA (1kOhm). The internal resistance (output impedance) is 0.17 Ohms (170 milliohms). The unit is durable and maintenance-free. It measures approximately 1.5″ x 2.25″ x 1.75″.
Calibration is available any time for 40.00USD with fast turn-around time. Contact kaysert on the eBay email system for calibration service, or see our calibration listing . Test equipment and interconnect cords are not included.
Questions, use the link below. Thank you for viewing our eBay.com listing!
The following information may be of use to certain buyers. Null-offset configuration data: The null setup (second photo) is as follows: Fluke 732B OUTPUT (-)ground(-) to OUTPUT (-)ground(-) on the ±0.0002% standard. Power Supply 14.5VDC (+) and (-) to INPUT of the 0.0002% DC standard; (+) OUTPUT (+) of Fluke 732B to DMM high; 10VDC (+) OUTPUT (+) of 0.0002% DC standard to DMM low.
Some qualitative aspects:
this device is a revolutionary voltage standard at an affordable price. If you want to get your lab synced to the SI volt, our 0.0002% standard provides one possible way to do it. The device does not require continuous power. It will endure hard power cycling and retain its absolute accuracy of ±2ppm. To date, the results show drift to be < 3.0ppm/120 days! Tests to determine the effects of relative humidity on the output voltage demonstrate a 17% RH range between 25% and 42% has no measurable effect on output voltage. Based on tests done with each unit, and also a number of unsolicited test results from credible outside sources, we have estimated the actual absolute error of our ±0.0002% DC standard to be < ±2ppm, with 99% confidence. The error at the calibration temperature (documented on the included calibration certificate) is between 1.5uV and 3uV (0.15ppm and 0.3ppm); confidence 99%. We have received credible reports from all over the world praising our products.
A good application:
In many instances it is more desirable to ship our unit (shipping weight = 4 oz.; 112 gm) from place to place in a powered-down state, than to ship a Fluke 732B in a powered-up state, because the accuracy required for a particular application may be less than the 732B provides, and shipping costs are much less.
We furnish a traceable certificate with each unit. All units are burned-in for a year or more before final calibration and shipment!
The buyer can have this device calibrated 25 times for the cost of one calibration of a Fluke 732B! Nothing else will get the SI volt in the door at a lower cost. We have 100% positive feedback. We’ve sold hundreds of voltage standards on eBay! They have been extensively tested. And we are continuously improving the design and performance.
We have two complete DC calibration labs that are checked against each other four times per year. We’ve done seven years of R&D and testing on this unit.
Among our buyers are four United States Government defense contractors, three calibration labs, two University physics departments, an industrial R&D lab, the national standards lab in Sparta, Laconia, Greece, and buyers in the following nations:
Argentina
Australia
Austria
Belgium
Bulgaria
Canada
Denmark
Finland
France
Germany
Greece
Hungary
Ireland
Israel
Italy
Japan
Latvia
Malaysia
Malta
Netherlands
Norway
Russian Federation
Slovenia
South Africa
Spain
Sweden
Switzerland
UK
USA
Thank you for viewing our eBay.com listing. Questions, use the link above.