Got a pressure relief valve that you need tested? Using our Pressuredaq system, we can accurately capture the “cracking” and reseat pressures. And we don’t just check it once and call it good. Our standard testing procedure is to crack the valve at least 10 times at a sampling rate of 10 samples/second to make sure that it’s repeatable. From 100 psi to 30,000 psi, we’ve got you covered.
ITS-90 PRT Resistance to Temperature Spreadsheets
If you’re like us, you use PRTs but not so much that you want to purchase a dedicated PRT thermometer when you have a perfectly capable DMM that will measure resistance for you.
Well, today’s your lucky day. We deciphered the ITS-90 reference and deviation equations for you and put a couple of subranges into spreadsheets. Well . . . OK . . . we put the subranges that WE use into the spreadsheets. There are two files: one is an Excel spreadsheet, the other is a ZIP file that contains a Numbers template. We use Apple computers and Numbers is our primary spreadsheet. We do recognize that 99.99% of the industrial/business community uses Windows and Excel, so we figured this would only be a help to everyone if we made an Excel spreadsheet that they/you could use.
Need a different range? Let us know and we’ll see what we can do. Find an error or omission? Let us know about that, too.
Uncertainties
“A measurement result is only complete if it is accompanied by a statement of the uncertainty in the measurement.” That’s quoted from Measurement Good Practice Guide No. 11 (Issue 2), A Beginner’s Guide to Uncertainty of Measurement, published by NPL. “ISO/IEC 17025 requires calibration laboratories to report, in the calibration certificate, the uncertainty of measurement . . .” That’s taken out of ILAC-P14:12/2010.
There are lots of guides and technical papers out there that describe how uncertainties should be calculated. Uncertainty analyses, like calibrations, can be extremely complex or fairly simple. Most guides say that the uncertainty analysis should be commensurate with the calibration. That means that for most typical industrial type calibrations, the uncertainty analysis is going to be fairly straight forward. Here’s the problem: very few calibration labs actually report uncertainties . . . unless you want to pay through the nose.
We decided to make uncertainty reporting for our calibrations standard. Yes, there are those calibrations for which they will not be reported: pass/fail calibrations, for instance. But, the vast majority of calibrations that we perform have the uncertainty reported right there on the report of calibration in the units that the measurement is reported in.
Simple . . . Different . . . Better
Is your calibration data yours?
On the surface, that may seem like a simple question, but ask your calibration provider. What happens if you lose a report of calibration or need data after a “short form” was issued?
We feel that once you pay us for the calibration, the data is yours. You won’t have to pay us again if you need another copy of your report of cal and we always provide data. Having been in the industry for about 18 years, it was aggravating to tell clients that they had to pony up more money for a lost report or worse to have to pay for a duplicate report from a calibration provider. We decided to turn that notion on its head.
Additionally, your data is backed up hourly on site and also hourly to an encrypted offsite backup provider. So, you can be confident that when you need a copy of your data, we’ll have it waiting for you.
Simple . . . Different . . . Better
Calibration defined
The term “calibration” can have quite a few different meanings. Manufacturers will often use the term to describe the initial setting of an instrument to a known value or values. It can mean to compare an instrument to a known standard and subsequently make adjustments to the instrument to more closely align its indication with the reference standard indication.
We use the term “calibration”, as defined by OIML V 2-200-2010 International Vocabulary of Metrology-Basic and General Concepts and Associated Terms (VIM), to mean:
operation that, under specified conditions, in a first step establishes a relation between the quantity values with measurement uncertainties provided by measurement standards and corresponding indications with associated measurement uncertainties and, in a second step, uses this information to establish a relation for obtaining a measurement result from an indication.
There are a few notes that go along with that definition, the most important of which is
Calibration should not be confused with adjustment of a measuring system, often mistakenly called “self-calibration”, nor with verification of calibration.
We perform calibration and when possible will adjustment your instrument to more closely align with our standards. And as always and when possible, “As Found” readings are taken and reported before any adjustments are made.