B
bkarthikeyan
How to conduct MSA on Voltmeters,Ammeters fixed on Machine ?
MSA on Process Instruments (Voltmeters, Ammeters Fixed on Machine)
D
David DeLong
First of all, I would not perform a MSA study on any gauge family that was not in the Control Plan (per TS 16949).
If you really wanted to perform a study anyway, one would need 10 samples of product that would be measured by the instrument. If that cannot be done, then I would go to stability testing in which I would use only 1 sample and measure it many times and plot it on a individuals and moving range chart.
If one could get 10 samples of product, I would perform it the R & R study like any other study but I have a feeling that the R&R values would be rather low.
Since these instruments are process measuring devises, it may not be possible to perform the either an R & R or a stability study and, if that case, they are not conducive to MSA studies.
Good luck.
If you really wanted to perform a study anyway, one would need 10 samples of product that would be measured by the instrument. If that cannot be done, then I would go to stability testing in which I would use only 1 sample and measure it many times and plot it on a individuals and moving range chart.
If one could get 10 samples of product, I would perform it the R & R study like any other study but I have a feeling that the R&R values would be rather low.
Since these instruments are process measuring devises, it may not be possible to perform the either an R & R or a stability study and, if that case, they are not conducive to MSA studies.
Good luck.
Do these gages actually measure product or do they monitor the process in real time?
MSA applies when measuring product. If these monitor the process, calibration should be sufficient. You could perform a stability study using the calibration standard and use the short term variation to estimate Repeatability.
MSA applies when measuring product. If these monitor the process, calibration should be sufficient. You could perform a stability study using the calibration standard and use the short term variation to estimate Repeatability.
AMIT BALLAL
Super Moderator
Hello Mr.Miner!!
I have a doubt, in our control plans, we have specified ammeters & voltmeters as a measurement technique.
And 7.6.1 clause specifies that,
Statistical studies shall be conducted to analyse the variation present in the results of each type of measuring and test equipment system. This requirement shall apply to measurement systems referenced in the control
plan.
How can we get exclusion from this requirement?
We haven't done any MSA study of ammeters & voltmeters, but still we are planning & searching about how it can be done.
Please guide !!!!!
Thanks,
Amit
(in advance)
I have a doubt, in our control plans, we have specified ammeters & voltmeters as a measurement technique.
And 7.6.1 clause specifies that,
Statistical studies shall be conducted to analyse the variation present in the results of each type of measuring and test equipment system. This requirement shall apply to measurement systems referenced in the control
plan.
How can we get exclusion from this requirement?
We haven't done any MSA study of ammeters & voltmeters, but still we are planning & searching about how it can be done.
Please guide !!!!!
Thanks,
Amit
(in advance)
If you are using the meters as part of your control plan for a 'special process' or if you are using them for directly measuring and accepting your product then you probably cannot get an exception.
A MSA study is fairly easy, so I am not sure what you are unsure about? Do you not know how to perform one? Or is there something about your use of these Gage's that makes the repeat measures somewhat difficult logistically? More information on how you are using these instruments and what you are measuring will be helpful...
Miner has many very useful blog postings that can help you on how the testing is done and analyzed...the link is at the top of the page.
A MSA study is fairly easy, so I am not sure what you are unsure about? Do you not know how to perform one? Or is there something about your use of these Gage's that makes the repeat measures somewhat difficult logistically? More information on how you are using these instruments and what you are measuring will be helpful...
Miner has many very useful blog postings that can help you on how the testing is done and analyzed...the link is at the top of the page.
AMIT BALLAL
Super Moderator
Thanks!!
We are using Ammeters & voltmeters for monitoring qualified process parameters on welding (a special process).
My doubts are as follows:
Can we perform MSA study on these measuring techniques, as these doesn't measure product?
Does MSA 4th edition manual specify, MSA is applicable while measuring product only?
Thanks,
Amit
Last edited:
The MSA manual 4th Ed., Page 3 uses an example of measuring the temperature of feed material. This and other examples imply that the intent of the MSA manual is for both part characteristics and process parameters.
However, the governing document will be the requirements of the actual standard (e.g., ISO 9001, ISO TS16949) plus any customer specific requirements. Since your gages are critical controls for a special process, I am dubious that you would be able to obtain an exemption from the requirements.
However, the governing document will be the requirements of the actual standard (e.g., ISO 9001, ISO TS16949) plus any customer specific requirements. Since your gages are critical controls for a special process, I am dubious that you would be able to obtain an exemption from the requirements.
What was the uncertainty of the in-situ calibration of those instruments? that should be considered.
