Maximum Permissible Error for Monitoring and Measurement Devices

M

mickng

#1
Hi,

I read the article before which related to Permissible error for monitoring and measurement devices. However, I can't find this article anymore...

I was told there are few ways to determine the permissible for the devices;

1) Follow the testing standard recommendation ( if there is available ) or
2) Follow supplier recommendation ( if the salesman is technical enough)
3) Rule of thumb - own calculation based on 1/3 of the product's tolerance.

ISO10012:2003 saying that the permissible might determined by metrological function, then does the above method acceptable?

I was learn that previous standard stated 1/10, then 1/4 and latest recommendation is 1/3, am I right?

Anyone can offer a help to solve my doubt..

TQ

Mick:truce:
 
Elsmar Forum Sponsor

BradM

Staff member
Admin
#2
Well, hello there!

I'm really not a subject matter expert, but I'll give it a stab.

When you state permissible error, to what are you comparing? If you are talking about how much error an instrument can have, that will depend on what calibration tolerances you establish for that particular instrument.

Or, do you have in mind some comparison of that instrument tolerance to some specification within the process?

As far as what type of accuracy your instrument needs, a general rule of thumb is 4-1. NOTE: That's general, and there are many factors that need to be considered. But in general, the accuracy of your measuring instrument should be four times greater than the process requirements.

Not sure if that helps.
 

harry

Super Moderator
#5
Welcome Mick,

If I am not mistaken, these are rules of thumb.
1:10 normally refers to resolution of instrument
1:4 is what Brad mentioned earlier
1:3 refers to tolerance and uncertainty. Tolerance should be greater than 3 times uncertainty.

Can any fellow covers here confirm this or point us in the right direction.

Thanks in advance.
 
M

M Greenaway

#6
Harry

Those rules of thumb are ok as a broadbrush guideline, however the only way to determine if a piece of measuring equipment (or indeed a measurement process) is good enough is to conduct MSA study. Certainly this must be done on critical or safety characteristics.
 

harry

Super Moderator
#7
Harry

Those rules of thumb are ok as a broadbrush guideline, however the only way to determine if a piece of measuring equipment (or indeed a measurement process) is good enough is to conduct MSA study. Certainly this must be done on critical or safety characteristics.
Thanks. I am in complete agreement with your advice especially after some experience with TS implementation.
 
M

mickng

#8
Hi,

I managed to find MIL-STD-45662A, found out that the previous recomendation is 25% of the product tolerance. I am still looking for ISO10012-1,-2:1998 Version which I read before that indicate the 1:3 of the product tolerance.

I agreed of MSA but it does not indicate much on accuracy requirement which is the permissible error of the devices, it focus more in precision study. The question is if TS auditor ask on how to read the calibration certification, then auditee need to answer how he compared the measurement uncertainty with permissible error. MSA indicates that we need calibrate our device prior GR&R study...right.

Anyway I have both MIL-STD-45662A and ISO10012:2003, let me know if anyone interested..

TQ

:thanx:
 
P

potdar

#9
MSA has to be conducted on calibrated instruments only. It encompasses too many variables within the results.

The shop floor, quality and calibration people use different language. I shall therefore use the schoolboy language and define what I say - at a risk of sounding too elementary. These are thumb rules that the standards will overrule.

Product / dimension tolerance limit

MMD least count - prefarably 1/10 of tolerance, 1/4 of tolerance max.

Calibration error - Difference between standard value being measured and measurement shown by the MMD.

Acceptable calibration error - defined by the instrument standard or 1/3 of least count max.

Comparison between actual calibration error and acceptable calibration error will decide whether the the MMD is 'in calibration'.

I have examples of my clients using some 'calibrated' vernier callipers in their foundry division. These were considered out of calibration by their machining division located in the same compound.
 
Thread starter Similar threads Forum Replies Date
Marc Definition MPEE - Maximum Permissible Error for Length Measurement Definitions, Acronyms, Abbreviations and Interpretations Listed Alphabetically 0
N ASME B89.1.13 question regarding Resolution and Maximum Permissible Error General Measurement Device and Calibration Topics 3
M What is the maximum permissible period of delaying the validation of equipment? Other Medical Device Regulations World-Wide 4
J IEC60825 - Laser Safety - Calculating Maximum Permissible Exposure Correctly Other ISO and International Standards and European Regulations 1
N Maximum mains voltage used when applying 60601 IEC 60601 - Medical Electrical Equipment Safety Standards Series 2
R Clinical accuracy and repeatability of IR(infrared) thermometer, no maximum error criteria is recommended in ISO Other Medical Device Related Standards 11
D Determining the the maximum number of reprocessing cycles of attachments CE Marking (Conformité Européene) / CB Scheme 2
Marco Bernardi MMC & LMC modifiers and CMM measuring techniques like diameter least squares and circularity or minimum/ maximum diameter Calibration and Metrology Software and Hardware 5
G Need to change KPI we called NC parts (maximum 3%.) to FTQ (first time quality) IATF 16949 - Automotive Quality Systems Standard 4
Judy Abbott Increase the maximum allowable dose for E-beam sterilization Reliability Analysis - Predictions, Testing and Standards 2
M Maximum Height for the stored material or stock materials Occupational Health & Safety Management Standards 1
S How to calculate the maximum allowable hysteresis of a pressure gauge General Measurement Device and Calibration Topics 1
F Irradiation Sterilization Validation Maximum Dose - VDmax 25 method (ISO 11137) EU Medical Device Regulations 2
V Acceptable maximum RSD (relative standard deviation) for an sample size Gage R&R (GR&R) and MSA (Measurement Systems Analysis) 1
A Maximum bubble volume for subcutaneous injection IEC 60601 - Medical Electrical Equipment Safety Standards Series 0
D Calibration of a Width Gage Slot with an Attribute Gage - Maximum Width Condition General Measurement Device and Calibration Topics 16
B Maximum Material Condition with Bonus - Determine Cpk for this one kpc Measurement Uncertainty (MU) 2
V Correlating Maximum 'Range' of Values for a given "RSD" (Control Limits) Statistical Analysis Tools, Techniques and SPC 3
C Q as the Datum Maximum Material Condition then MINUS 0.020 Inspection, Prints (Drawings), Testing, Sampling and Related Topics 1
I Minimum and Maximum Validation Batch Size Requirements Qualification and Validation (including 21 CFR Part 11) 3
R Maximum Reverse Speed Limit for Powered Wheelchairs Other US Medical Device Regulations 2
C Maximum acceptable Tolerance - Uncertainty Ratio (TUR) General Measurement Device and Calibration Topics 2
R ISO 14644-1 maximum particulate concentration limits concern Other ISO and International Standards and European Regulations 2
K Maximum Material Condition on Diameter Tolerance Inspection, Prints (Drawings), Testing, Sampling and Related Topics 4
L Maximum voltage for IEC 60601? IEC 60601 - Medical Electrical Equipment Safety Standards Series 9
M Zero Tolerancing on True Position using MMC (Maximum Material Condition) Inspection, Prints (Drawings), Testing, Sampling and Related Topics 6
K Step by Step Gauge R&R with 10% maximum allowable Gauge Error Gage R&R (GR&R) and MSA (Measurement Systems Analysis) 1
S Aseptic Processing - Maximum SAL using Aseptic Processing for Sterilization Other ISO and International Standards and European Regulations 4
optomist1 Maximum Shift Tolerance Restrained Part - Calculation of Datum Shifts Inspection, Prints (Drawings), Testing, Sampling and Related Topics 7
K Is there a "maximum time limit" for nonconformity to fix? Internal Auditing 11
S What's the maximum post limit in a day? Elsmar Cove Forum ToS and Forum Policies 6
R Maximum allowed eccentricity for any shaft or hole diameter Misc. Quality Assurance and Business Systems Related Topics 7
R Can maximum ambient operating temperature be specified higher than 40C? IEC 60601 - Medical Electrical Equipment Safety Standards Series 5
D Process Capability Study which involves MMC (Maximum Material Condition) Capability, Accuracy and Stability - Processes, Machines, etc. 8
S Maximum error of a z value from sample data Inspection, Prints (Drawings), Testing, Sampling and Related Topics 3
G ANSI & ASME regardless of Maximum Material Condition when none is specified Various Other Specifications, Standards, and related Requirements 3
D ANSI IPC A-610 Maximum Jumper Wires Allowed on Boards by the IPC Standard Various Other Specifications, Standards, and related Requirements 1
D How to inspect maximum allowable contaminate Inspection, Prints (Drawings), Testing, Sampling and Related Topics 2
2 ISO 9001 should be implemented before CMMI for maximum effectiveness? Quality Manager and Management Related Issues 2
M Ergonomics - Human Hand - Maximum force - Wheel/Flywheel - Help ASAP :) Human Factors and Ergonomics in Engineering 8
F How to statistically determine the maximum performance life of a chemical Statistical Analysis Tools, Techniques and SPC 4
Chennaiite Process Capability for a specification with Maximum Material Condition (MMC) Statistical Analysis Tools, Techniques and SPC 4
F Maximum walking distance for assembly line worker Human Factors and Ergonomics in Engineering 28
M What is maximum limit for MU (Measurement Uncertainty) or acceptable criteria? Measurement Uncertainty (MU) 5
S GD&T Rule 1: Gage size for form check at MMC (maximum material condition)? Inspection, Prints (Drawings), Testing, Sampling and Related Topics 9
D How to Measure a Diameter - Average or Maximum/Minimum? Inspection, Prints (Drawings), Testing, Sampling and Related Topics 25
N QMS Scope length limited to 10 to 15 words maximum - How is that possible? ISO 9000, ISO 9001, and ISO 9004 Quality Management Systems Standards 5
L Internal threads - Maximum / Minor accept/reject diameter inspection Inspection, Prints (Drawings), Testing, Sampling and Related Topics 6
Q Maximum minor thread diameter of UNF internal threads Inspection, Prints (Drawings), Testing, Sampling and Related Topics 7
E Corrective and Preventive Action - State Maximum time for follow-up required? ISO 9000, ISO 9001, and ISO 9004 Quality Management Systems Standards 14

Similar threads

Top Bottom