Municipal Instrumentation Calibration

[dpslusser]

I have a customer (Municipal Sewage Treatment Plant) that has been having some "Joe Schmo" do there calibration on all their instrumentation. A few months ago, they fired him as their integrator and are now looking to my company for help. The automation side we can handle just fine, as well as installation and commissioning of instrumentation. It is the yearly "calibration" that the customer is required to have done on ALL their instrumentation. I have worked on a few hundred instruments over the past few years from different manufactures belonging to all sorts of customers. And slot of those instruments are calibrated as well. But the companies that do the calibration are not to different from mine, and I can print calibration stickers on my laser printer the same way most of these other companies do.So one question that has always been stuck in my mind...if I have the calibrated equipment to test the customers instrumentation, what is stopping me from saying I can calibrated instrumentation??? A quick google search for other companies who do on-site instrument calibration don't state anything regarding government (ISO, ANSI, NIST) certification. What was interesting though was that I did find that some companies state that there EQUIPMENT is ISO, ASNI or NIST traceable, but nothing stating that there calibration PROCEDURES are government certified in any way. I hope someone could help shed some light on this.Thanks in advanced!!

 

[petersonra]

I don't recall there being any "government" mandated standards for calibrating instruments.

There are some fairly good guidelines that various entities have put together for how calibration is handled.

It is not rocket science. A few grand in training and whatever calibration equipment is required to calibrate whatever instruments you want to deal with and you are all set.

I will point out that some kinds of calibration are radically different than just pumping up a hand tester for a pressure meter. Some calibrations will require standard solutions for doing your calibrations and it can require some expertise to do these. It is not as simple most of the time as just dropping the sensor in a jar of standard solution and reading out the results.

However, there is a reason why instrument techs are often considered the creme of the crop of the trades in most plants.

 

[dpslusser]

Thanks for the reply.

I have setup a lot of analytical instruments and it seems that the startup is not to different than the calibration. I have no problem calibrating these types if instruments. Several turbidity, pH/orp's and CL-17 chlorine analyzers are a good example of what they have. Being contracted by a pharmaceutical company for a year provided free training. Lol.

I just want to make sure, if I am to buy cal stickers and slap my companies name on them after I calibrate them, we won't get in trouble.

 

[John120/240]

Similar, but its not. In Kansas, the Dept of Agriculture calibrates fuel pumps. I am sure somebody calibrates vehicle scales, produce scales etc. I would imagine all of these calibrations would be traceable to the NIST if you dig deep enough. Your instruments would need to be calibrated to some standard otherwise your calibration services don't mean diddly. Check out NIST...http://www.nist.gov/calibrations/index.cfm

 

[dpslusser]

I do use calibrated equipment that is send in to Acucal every year. My process meters and RTD's have to be sent it every year.

I get what your saying though. It's probably the same thing as Weights and Measures here in PA. They cert all the gas stations and weigh scales on the interstates.

 

[Electric-Light]

This thread misses the big picture. Calibration is like supervised urine testing in maintaining a chain of custody of everything involved.

Calibration is more about maintaining integrity/curbing fraid as the measured values often tie directly to money as well as sales and marketing claims.

For example, there's every incentive for decorative light emitting devices to use a light measurement device that reports on the high side and watt measurement device that reports on the low-end, and a thermometer that reports low, so it can artificially boost the performance specs.

Remember that measured values often directly tie to money or butt covering.

 

[GoldDigger]

Actually, in some cases you would want temperature measurements to read high, so that the equipment under test will work properly at higher ambient temperatures.

 

[Jraef]

I think it depends on the local rules and regs, and on what type of instrumentation. Around here, anything that is used in revenue must be certified, which generally takes place with calibration. Most instruments used in a Waste Water Treatment Plant however are not directly involved in revenue, that's why a lot of integrators will offer that service (I did when I was an integrator). The gotcha that has come up is if the facility uses flow meters to determine how much to bill certain districts if for example they have separate intake facilities. I've come across that a couple of times, it's rare, but just watch out for it. I got my you know what in the wringer with the state over that.

My other caution is just in general business practices if launching this. Don't quote it sight unseen, always do a survey of all details of each instrument they want calibrated, then research each one before quoting. If the instrument is no longer made or supported, or worse yet the manufacturer is out of business, finding out how to do calibration can become a nightmare that can eat you alive of you didn't cover the time it takes in your quote. Customers do NOT want to pay for on-the-job learning if they give you a contract for calibration services.

 

[dpslusser]

Thanks Jraef

 

[Electric-Light]

I think it depends on the local rules and regs, and on what type of instrumentation. Around here, anything that is used in revenue must be certified, which generally takes place with calibration. Most instruments used in a Waste Water Treatment Plant however are not directly involved in revenue, that's why a lot of integrators will offer that service (I did when I was an integrator).

Yes, but it's just like a drug test.
The test readings directly relate to ENVIRONMENTAL REGULATION COMPLIANCE, just as drug tests relate to pass/fail.

 

[petersonra]

Thanks for the reply.

I have setup a lot of analytical instruments and it seems that the startup is not to different than the calibration. I have no problem calibrating these types if instruments. Several turbidity, pH/orp's and CL-17 chlorine analyzers are a good example of what they have. Being contracted by a pharmaceutical company for a year provided free training. Lol.

I just want to make sure, if I am to buy cal stickers and slap my companies name on them after I calibrate them, we won't get in trouble.

It depends a lot on what you mean by "trouble".

Most instruments can be readily calibrated. As you mentioned it is not a lot different in many cases than a start-up procedure, at least superficially. The key is that there can be both substantial and quite subtle differences between a start-up procedure and a calibration procedure. For instance, some sensors require cleaning as part of the periodic calibration. Cleaning is not required at start-up because it is already clean. Some pump colorimeters require parts be replaced as part of the calibration procedure. Older pH cells often needed to have part of the actual pH cell replaced as part of calibration.

Modern instruments tend to be very easy to calibrate compared with instruments of just 10 years ago. It may turn out that what looks fairly lucrative right now is going to become a crowded field fairly quickly just because it is so much easier to calibrate things these days, and the barrier to entry into the field has become much lower. Everyone with a HART communicator and a Fluke thinks they can calibrate anything these days, and it is not real far off from the truth.

 

[iwire]

For example, there's every incentive for decorative light emitting devices to use a light measurement device that reports on the high side and watt measurement device that reports on the low-end, and a thermometer that reports low, so it can artificially boost the performance specs.

Remember that measured values often directly tie to money or butt covering.

Seriously, keep your LED hatred to LED threads.

 

[mjf]

Seriously, keep your LED hatred to LED threads.

:happyyes::thumbsup::thumbsup::thumbsup::thumbsup::thumbsup::happyyes:

 

[Electric-Light]

It depends a lot on what you mean by "trouble".

Most instruments can be readily calibrated. As you mentioned it is not a lot different in many cases than a start-up procedure, at least superficially. The key is that there can be both substantial and quite subtle differences between a start-up procedure and a calibration procedure. For instance, some sensors require cleaning as part of the periodic calibration. Cleaning is not required at start-up because it is already clean. Some pump colorimeters require parts be replaced as part of the calibration procedure. Older pH cells often needed to have part of the actual pH cell replaced as part of calibration.

Modern instruments tend to be very easy to calibrate compared with instruments of just 10 years ago. It may turn out that what looks fairly lucrative right now is going to become a crowded field fairly quickly just because it is so much easier to calibrate things these days, and the barrier to entry into the field has become much lower. Everyone with a HART communicator and a Fluke thinks they can calibrate anything these days, and it is not real far off from the truth.

You still need the background knowledge. The things you need to know are quite involved.
The reference inputs and instruments need to have current calibration.

http://asq.org/cert/calibration-technician/bok

 

[petersonra]

Not real long ago, I read a blurb that suggested regular calibration of certain instruments (the blurb specifically mentioned temperature and pressure xmtrs) might well become a non issue in the not too distant future.

The cost of the transmitters is coming down fast enough that it may become more cost effective to replace them rather than try and calibrate them, and the other trend is that very few such instruments ever go out of calibration enough to matter any. The smart transmitters may well be able to determine when a calibration is actually needed and until it either calls for a calibration or dies entire, the instrument may go for decades not needing any attention at all.

 

[Electric-Light]

Not real long ago, I read a blurb that suggested regular calibration of certain instruments (the blurb specifically mentioned temperature and pressure xmtrs) might well become a non issue in the not too distant future.

The cost of the transmitters is coming down fast enough that it may become more cost effective to replace them rather than try and calibrate them, and the other trend is that very few such instruments ever go out of calibration enough to matter any. The smart transmitters may well be able to determine when a calibration is actually needed and until it either calls for a calibration or dies entire, the instrument may go for decades not needing any attention at all.

Calibration doesn't always entail "calibration adjustment"
"calibration check" is a part of calibration process.

 

[topgone]

Not real long ago, I read a blurb that suggested regular calibration of certain instruments (the blurb specifically mentioned temperature and pressure xmtrs) might well become a non issue in the not too distant future.

The cost of the transmitters is coming down fast enough that it may become more cost effective to replace them rather than try and calibrate them, and the other trend is that very few such instruments ever go out of calibration enough to matter any. The smart transmitters may well be able to determine when a calibration is actually needed and until it either calls for a calibration or dies entire, the instrument may go for decades not needing any attention at all.

This is true. With HART capable transmitters, you can see which part is showing correct values and the equipment might not even need calibrating.

 

[Smart $]

Not real long ago, I read a blurb that suggested regular calibration of certain instruments (the blurb specifically mentioned temperature and pressure xmtrs) might well become a non issue in the not too distant future.

...

Hush now. That'll be taking food from this baby's mouth.

Calibration doesn't always entail "calibration adjustment"
"calibration check" is a part of calibration process.

That's right!

This is true. With HART capable transmitters, you can see which part is showing correct values and the equipment might not even need calibrating.

No it is not. Verifying calibration requires comparison to a certified accurate measurement standard (i.e. the physical kind, not the written kind) with typically better precision. They have yet to invent the process where you can sit in the control room and calibrate an in-the-field process measurement using a transmitter.

This has been a staple since long before any of us were born and will continue to be the case well into the near future... and will always be the case where revenue is involved :happyyes:. Consider the simple scenario where you purchase X dollars worth of a precious metal. How do you know you are getting the agreed upon exchange rate ($/mass)?

 

[zog]

We use these guys, you can send stuff in to them or if you have a lot of stuff they will come to your facility. They are actually coming here next week to calibrate all of my test equipment, takes them about a week to do all of my stuff on site.
http://www.electricaltestinstruments.com/

 

[topgone]

No it is not. Verifying calibration requires comparison to a certified accurate measurement standard (i.e. the physical kind, not the written kind) with typically better precision. They have yet to invent the process where you can sit in the control room and calibrate an in-the-field process measurement using a transmitter.

Of course, you'll have standard/s to compare with what value the communicator tells you How else can one know without comparing?