Instrument calibration vital to ensuring test reliability at YPG

In today’s industrial world, electronic measurement devices provide essential information humans used to make all sorts of decisions. From predicting the weather, analyzing soil, generating medical details, or repairing automobiles, accurate measurements are essential.

Measurement devices must be verified on a regular basis to ensure they reliably provide correct data. This is done through calibration by verifying the performance of an item and making adjustments to ensure it is within specifications.

The calibration lab follows established procedures for each calibration and makes every effort to minimize the uncertainty of the measurement. Measurement uncertainty is a calculation of how close a measurement is to the true value. Any factor that affects the calibration must be taken into account including connections, environment, as well as the technician’s ability to repeat the measurements consistently.

Since Yuma Proving Ground’s primary mission is to test weapon systems and munitions for America’s military forces, equipment calibration is a necessity. A rigorous calibration regimen helps ensure the quality of the tests performed at the proving ground each day.

YPG’s calibration is performed by five people making up the USATA Support Center-Yuma (U.S. Army Test Measurement and Diagnostic Equipment Activity). Headed by Lorrain Cook, a 30-year USATA veteran, the calibration lab has been supporting YPG for over 50 years. Cook says TMDE is very much connected to YPG because the work it performs fully supports the mission, despite the fact that the organization is technically a tenant.

“Many, many years ago, TMDE was, organizationally, a part of YPG reporting to the commander,” she explained. “The decision was eventually made to separate us out to ensure we would always remain a neutral party that could not be influenced in any manner.”

A wide variety of sophisticated electronic equipment dwells within the lab. These include calibration systems for performing calibration on multimeters, oscilloscopes, spectrum analyzers, signal generators, and much more. The huge variety of equipment calibrated for YPG testers varies from simple torque wrenches to complex microwave systems.

“Our goal is to use the equipment to produce measurements as accurate as humanly possible,” said Iain Yorke, calibration technician.

To this end, equipment is frequently upgraded to remain on the cutting edge, either at the instructions of higher headquarters at Redstone Arsenal, Al., or on the recommendation of the TMDE Support Center-Yuma lab itself.

“Technology is constantly moving forward,” said Cook. “We have to meet calibration needs here to remain fully capable at all times. We have no choice but to step up.”

Like calibration labs elsewhere, regular inspections take place to ensure equipment functions correctly, operating procedures are appropriate, training occurs, and detailed record-keeping takes place. A group of inspectors spent a week at the TMDE lab early this year at which they examined numerous procedures and records, including watching people do their work. The inspection was concluded with a “no findings” report and the lab received an Outstanding TMDE Program Award.

“We maintain a huge database and work hard at what we do,” said a beam- ing Cook. “This kind of an inspection result is hard to achieve and it shows how seriously we take our work, as well as the technical competence of personnel here.”

She estimates the inspection team will visit again in 18 to 24 months. If a critical failure had been identified, a return inspection would be scheduled much sooner.

Calibration is vitally important wherever measurements are important, and that’s the case at Yuma Proving Ground, for it enables customers to have confidence in the results of their test programs. The ultimate beneficiary, however, is the American Soldier, who is able to have full confidence in the reliability of his or her equipment.

Chuck Wullenjohn is the public affairs officer at the U.S. Army Yuma Proving Ground. He can be reached at charles.c.wullenjohn.civ@mail.mil.