Routine Testing for Class I Medical Device

Marc

Hunkered Down for the Duration
Staff member
Admin
#11
IEC 62354 is a copyrighted document and as such can not be "shared" or linked to here in the forum so it is best not to ask.

Thank you for understanding.
Ninja'd
 
Elsmar Forum Sponsor

eldercosta

Starting to get Involved
#14
I hope it is OK adding a question to this topic instead of opening a new one on the very same subject.

I have the same problem as some users in this topic, how testing my Class I device in production. I have purchased IEC TR 62354:2014 because of ANNEX K, expecting it would give some directions on how production tests could be made in a way that could not be challenged by certification bodies. I was specifically aiming at the dielectric strength test voltages: I expected to have some bases to either reducing the test voltages or the time they are applied to the DUT (5s instead of 60s), as suggested on above posts. It turns out the ANNEX gave me no useful information at all. It is VERY vague and confusing (to me at least).

Where those 5s come from? Pure common sense or there is some rationale behind them that could be used as a rationale for testing.

The note of clause 5.1 of IEC 60601-1 (3.1) mentions either ANNEX K of 62354 or IEC 62353. But the latter does not prescribe dielectric strength tests. So once again we would be subject to the interpretation of the certification body.

Thank you in advance for your inputs.
 

Peter Selvey

Staff member
Moderator
#15
Dielectric strength is actually an ageing test for solid insulation, hence in theory it should not be done in production as it will age the insulation. It is also a white box test in the sense that it should be applied to individual parts such as wiring, transformers, opto-couplers, Y1/Y2 capacitors, connectors rather than the whole assembled equipment. Application to the assembled equipment risks stressing functional parts unnecessarily and there is no guarantee that the real insulation actually gets stressed.

This is an open and shut case, any agency that insists on blindly following the values in the standard for production tests on an assembled device should be and can be held accountable. It's almost certain that if you challenge it formally (with an explanation) the agency will back down. The problem tends to be the front line auditors that may not have the background/experience. This is something that I was taught when I started electrical safety testing back in 1987 but the theory seems to have fallen by the way at some stage.

A high voltage test can be a useful tool in production to detect assembly errors or other major mistakes. In this case though it is not an ageing test so the 60s is irrelevant. It just needs to be long enough to raise the voltage reliably. A value of 1-5s should be enough depending on the tester. It also needs to be first established that the application of the voltage will not damage any parts. Generally only some insulation paths can be tested this way, such as between mains and earth. Other paths and in particular 2 MOP paths are generally not practical.

If a manufacturer does use a test in production, the sample used for type tests should have undergone the same testing before any of the 60s type tests are applied. For example, if the planned production test is 60s, then the sample using in tested needs to be tested for a total of 120s.
 

eldercosta

Starting to get Involved
#16
Hello, Peter, thank you very much for your comment.

I agree with your comment above on the high voltage test being a useful tool to detect assembly errors.

I have done a fairly extensive search in the Internet and nearly every guide/article I found (from manufacturers of test equipment) only makes reference to the 60s tests, with only one exception, a guide by SCI ("Ultimate guide to electrical safety testing").

Anyway, after searching and reading, the context these readings provided made Annex K of IEC TR 62354:2014 making sense to me. It turns out the Annex does provide instructions and requirements for test durations of 1 second and 60 seconds on paragraph K.1 e).

Now I have a question regarding the 1 s test duration part of K.1 e). The text says:
1) If the test duration is 1s, the ouput is to be maintained within the specified range:
- when only a voltmeter having an input impedance of at least 2MOhms and a specimen of the product being tested are connected to the output terminals AND

-when a relatively high resistance is connected in parallel with the voltmeter and the product being tested, and the value of the resistance is gradually reduced to the point where an indication of unacceptable performance just occurs.
I am trying to make sense of the second dash above. I mean, what that resistance connected in parallel is for? And what one is trying to achieve by "reducing it gradually to the point were an indication unacceptable performance just occurs"? It looks like a sanity check (like the 120kOhms resistance used elsewhere to verify the tester is working properly), but the paragraph mentions the product being tested, suggesting it must be connected along the check; if the test needs to be repeated reducing the resistance gradually, what would be the point? What am I missing?

Thanks in advance for any input.
 

Peter Selvey

Staff member
Moderator
#17
Unfortunately that standard costs US$380 and so far I haven't had the justification to purchase it. I'd love to go through it as TR and Guides tend to be poorly prepared because they can hide behind the "just a guide" disclaimer more so than normative standard.

Can I ask, does the 1s test require an increased voltage? In other words, they give the option of 60s at the normal voltage or 1s for an increased voltage? If yes, then this still goes against the principles of dielectric strength testing since it is still ageing the insulation, which needs to be taken into account in the type test (whatever is done in production needs to be also done in advance of any type tests).

As text shown, yes, this looks like a validation check for the tester to make sure it can deliver the current/voltage. In a type test, it's required to have a larger tester with 100mA capacity, but in production this would be overkill and is more dangerous. Lower capacity devices could be OK as long as it can be shown to reach the required voltage reliably. This looks like just a validation, i.e. before set up, at least once a year or at most once a day.

My preference is to use ac and record the current as a double check. This again gives a good indication if anything is amiss for either the test set up or the equipment under test, and would reduce the need to frequently check the tester.
 

eldercosta

Starting to get Involved
#18
Hello, Peter.

Yeah, a lot of $ for just an ANNEX worth of information. :)

Answering your first question, no it does not require an increased voltage. Actually it does not state a voltage at all. The only thing it stipulates, right above the text I quoted, is the voltage value must not be lower than the "test value specified" (whatever it means) and not greater than 120% that value, regardless of the test duration.

As the Annex does not explicity state the voltage that must be used - paragraph a) just says "the stated a.c. value" - I think we could simply define whatever voltage we deem as adequate, but using the type test voltage values of the equivalent test points makes more sense to me and should require less explanation to the certification body. Simply beeing able to justify a shorter duration (1s) based on a standard (or TR in this case, referred by the main standard) is good.

Regarding the instrument, the requirements of the Annex are fairly easy to achieve with a good quality hipot and no specific current is specified so units that detect and break with a few mA must do fine. There are also some requirements about the output waveform being sinusoidal or boundaries if it is not perfecly sinusoidal, and also about the instrument being able to deliver a stable output voltage during the test.

Thanks for your comment on confirming my understanding on that dash paragraph.

BR

Elder.
 
#19
We are Class I medical device company with all our products being DC powered LVDS and none of the products have essential performance.
1.Do we need to re-test emissions and immunity tests and have a new test plan, if we want to transition from Edition 2nd- Edition 4th?
2.Currently we are complying to 2nd Edition and after performing gap analysis I've figured out that there is no change in emissions limits. Would we still need to re-test and have a new test plan in order to comply to 4th edition ? In case of audits can we show the 2nd edition and gap analysis report ?
 

Mark Meer

Trusted Information Resource
#20
...In case of audits can we show the 2nd edition and gap analysis report ?...
I'm not familiar with the 2nd edition of IEC 60601-1-2, but assuming you are correct that there are no changes to emission testing/requirements between the 2nd and 4th editions, then a gap analysis documenting this assessment will suffice as evidence of compliance to 4th edition requirements with respect to emissions.

That said, there are definitely several changes to the immunity requirements between the 2nd & 4th editions, so any gap analysis you document will presumably identify several gaps. ...you will have to fill these gaps (or document appropriate justification not to).
 
Thread starter Similar threads Forum Replies Date
M Routine testing of medical electrical systems - What specific electrical safety tests should be performed? IEC 60601 - Medical Electrical Equipment Safety Standards Series 5
E Routine production tests - dielectric voltage withstand test IEC 60601 - Medical Electrical Equipment Safety Standards Series 4
N Heavy tare to simulate high load in a routine sensitivity test of a floor scale? General Measurement Device and Calibration Topics 3
T Nonconforming product at customer detected by a routine inspection by field service Nonconformance and Corrective Action 9
N Referencing of a standard's year in routine regulatory compliance documents Other Medical Device Related Standards 3
M Medical Device News FDA - Eliminating Routine FDA news 14-09-18 - Re-Review of Third Party 510(k) Reviews Other US Medical Device Regulations 0
N ISO 11135 Monitoring Routine ETO Sterilisation Parameters Other Medical Device Related Standards 3
C Dose Mapping - How to relate back to Routine Monitoring Position ISO 13485:2016 - Medical Device Quality Management Systems 3
B Number of Biological Indicators for Routine Monitoring of ETO Sterilization Cycle Other Medical Device Regulations World-Wide 8
J FDA Routine Inspection Pre-Anouncement - What will be checked? 21 CFR Part 820 - US FDA Quality System Regulations (QSR) 7
M Identifying Routine and Non-Routine Activities: OSHA OHSAS 18001 Occupational Health & Safety Management Standards 6
S How you define 'Normal & Abnormal' Conditions and 'Routine & Non-routine' Activities ISO 14001:2015 Specific Discussions 8
J Routine test for MD finished product IEC 60601 - Medical Electrical Equipment Safety Standards Series 1
RoxaneB Environmental Objectives - Do they need to be linked into with Routine Indicators? Miscellaneous Environmental Standards and EMS Related Discussions 6
RoxaneB Search for another name for "Standardization Process" or "Routine Management" Quality Tools, Improvement and Analysis 4
D Line clearance - Routine components in the prep room for universal use ISO 13485:2016 - Medical Device Quality Management Systems 8
R Inspection and Detection - Kit to production - Need an inspection routine Inspection, Prints (Drawings), Testing, Sampling and Related Topics 8
I IATF Lab Scope Testing Qualification and Competency Documentation ISO 9000, ISO 9001, and ISO 9004 Quality Management Systems Standards 3
N Chemical Testing on Medical Devices - Solutions in a container closure system (bag) EU Medical Device Regulations 0
M Comparing data from destructive testing Inspection, Prints (Drawings), Testing, Sampling and Related Topics 7
T Flammability testing Reliability Analysis - Predictions, Testing and Standards 0
E Manufacturers should develop a testing device for covid19 Service Industry Specific Topics 0
K When is Bioburden Testing Required? Other Medical Device Related Standards 4
K IEC 62304 - Testing Independance IEC 62304 - Medical Device Software Life Cycle Processes 5
A ANSI/AAMI versions of 60601-1-2 and related testing requirements Other Medical Device Related Standards 0
C Surgical mask stability testing (CE mark) EU Medical Device Regulations 1
Beliz Biocompatibility Testing for Laser Epilation Device EU Medical Device Regulations 2
C One Time Service Supplier - Temperature and Humidity Testing Service ISO 13485:2016 - Medical Device Quality Management Systems 5
D IEC 60601-1 - Service life testing IEC 60601 - Medical Electrical Equipment Safety Standards Series 8
P Flammability Testing of Aircraft Interior Materials Federal Aviation Administration (FAA) Standards and Requirements 0
N Usability testing required for FDA IDE (investigational device exemption)? Human Factors and Ergonomics in Engineering 3
E ASTM F2118 - Fatigue testing of bone cement - Changes between the 2003 and the 2014? Other Medical Device Related Standards 1
K Biocompatibility Testing - Multile products of different sizes and shapes US Food and Drug Administration (FDA) 2
S Requirement to Conduct New Shelf-life Testing? (re-do testing for design change) EU Medical Device Regulations 3
JoCam Mobile Patient Hoists and Electrical Testing Other Medical Device Related Standards 0
T Interlaboratory comparison or proficiency testing in destructive testing of welded joints ISO 17025 related Discussions 3
B ASTM E18-2020 - Rockwell testing standard changes? General Measurement Device and Calibration Topics 2
U Medical Device Design finalization testing ISO 13485:2016 - Medical Device Quality Management Systems 2
Jane's Like-for-like critical raw material change qualification - type of testing/ number of lots required ISO 13485:2016 - Medical Device Quality Management Systems 4
J Conflict of Interest Registrar/Notified Body/Testing House Quality Manager and Management Related Issues 4
M Inter-operator Variability Testing - Requirements for EU Medical Device Regulations 5
S High voltage testing - ISO 17025 - 7.2.2 Validation of methods and 7.3 Sampling ISO 17025 related Discussions 3
M Production approval testing - Alternative ideas for Validation Reliability Analysis - Predictions, Testing and Standards 4
JoCam MDL in Canada without Canadian Electrical Testing Canada Medical Device Regulations 0
T HF testing / Summative evaluation for MDDS class I necessary? Human Factors and Ergonomics in Engineering 2
K Diagnostic X-ray devices - Applicability of Biocompatibility Testing per ISO 10993-1 Manufacturing and Related Processes 7
K Proper document of SMPS used in infant warmer for IEC 60601-1 testing IEC 60601 - Medical Electrical Equipment Safety Standards Series 1
K Sequence of testing in IEC 60601-1 IEC 60601 - Medical Electrical Equipment Safety Standards Series 2
M Workplace Drug Testing in 2020 Misc. Quality Assurance and Business Systems Related Topics 9
W ASTM F1929 dye penetration test - Validation for in-house testing ISO 13485:2016 - Medical Device Quality Management Systems 13

Similar threads

Top Bottom