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Calibrated instruments and acceptance by auditor

Hi,

Some days ago I made a vi (calculating the mean current from a machine over
10 secs.) and this instrument is used for a withness test. Of course, once
this vi is made I can change the appearance of it by using for example other
constant values etc.

How can I be sure that this instrument is accepted by an auditor (or
notified body)?

I looked at the vi-properties and noticed that every time I change something
in the vi (and of course save the whole thing), the revision history is
changed by LabView. Is this a solid way of proof that nothing in the vi has
changed?

Maybe this helps in explaning my problem:

I use a transducer that gives a current of 0..20 mA linear to a the actual
current of 0..50A. I us
e the resistor from NI (249 Ohms, so the current will
be transformed to 0..5 Volts). For recalculation we found out that the
measured voltage should be multiplied with 10.2206. In this case the system
(transducer, shunt and DAQ-board) acts as a 0.5% class measuring instrument.
We also calibrated this system.

If I want to cheat on the measurement (for whatever reason it may be) I can
simply change the 10.2206 into another value. It's even possible to do it
without having the current revision number changed. (backup the revision
before the one changed and voila)

This means: problem with my auditor.

Does anyone have any idea about how to solve this 'problem'. I think this
can be of very big consequence to NI as more and more conventional apparatus
are 'build' by LabView.

Thanx
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Message 1 of 6
(3,088 Views)
Hi Boozz

You could password protect your VI.

Maybe you could have a calibration program, that only authorized users can have access, that saves the calibration data to a file
for test system to read and also generates a logged history of the changes.

Tim

Boozz wrote:

> Hi,
>
> Some days ago I made a vi (calculating the mean current from a machine over
> 10 secs.) and this instrument is used for a withness test. Of course, once
> this vi is made I can change the appearance of it by using for example other
> constant values etc.
>
> How can I be sure that this instrument is accepted by an auditor (or
> notified body)?
>
> I looked at the vi-properties and noticed that every time I change something
> in the vi (and of course save the whole thing), the revis
ion history is
> changed by LabView. Is this a solid way of proof that nothing in the vi has
> changed?
>
> Maybe this helps in explaning my problem:
>
> I use a transducer that gives a current of 0..20 mA linear to a the actual
> current of 0..50A. I use the resistor from NI (249 Ohms, so the current will
> be transformed to 0..5 Volts). For recalculation we found out that the
> measured voltage should be multiplied with 10.2206. In this case the system
> (transducer, shunt and DAQ-board) acts as a 0.5% class measuring instrument.
> We also calibrated this system.
>
> If I want to cheat on the measurement (for whatever reason it may be) I can
> simply change the 10.2206 into another value. It's even possible to do it
> without having the current revision number changed. (backup the revision
> before the one changed and voila)
>
> This means: problem with my auditor.
>
> Does anyone have any idea about how to solve this 'problem'. I think this
> can be of very big consequence to NI as
more and more conventional apparatus
> are 'build' by LabView.
>
> Thanx
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Message 2 of 6
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Mmm, idea!

Why isn't anyone from NI responding?


Timothy John Streeter schreef in berichtnieuws
39FDDFCA.FB16A9AE@tait.co.nz...
> Hi Boozz
>
> You could password protect your VI.
>
> Maybe you could have a calibration program, that only authorized users can
have access, that saves the calibration data to a file
> for test system to read and also generates a logged history of the
changes.
>
> Tim
>
> Boozz wrote:
>
> > Hi,
> >
> > Some days ago I made a vi (calculating the mean current from a machine
over
> > 10 secs.) and this instrument is used for a withness test. Of course,
once
> > this vi is made I can change the appearance of it by using for example
other
> > constant values etc.
> >
> > How can I be sure that this instrument is accepted by an auditor (or
> > notified body)?
> >
> > I looked at the vi-properties and noticed that every time I change
something
> > in the vi (and of course save the whole thing), the revision history is
> > changed by LabView. Is this a solid way of proof that nothing in the vi
has
> > changed?
> >
> > Maybe this helps in explaning my problem:
> >
> > I use a transducer that gives a current of 0..20 mA linear to a the
actual
> > current of 0..50A. I use the resistor from NI (249 Ohms, so the current
will
> > be transformed to 0..5 Volts). For recalculation we found out that the
> > measured voltage should be multiplied with 10.2206. In this case the
system
> > (transducer, shunt and DAQ-board) acts as a 0.5% class measuring
instrument.
> > We also calibrated this system.
> >
> > If I want to cheat on the measurement (for whatever reason it may be) I
can
> > simply change the 10.2206 into another value. It's even possible to do
it
> > without having the current revision number changed. (backup the revision
> > before the one changed and voila)
> >
> > This means: problem with my auditor.
> >
> > Does anyone have any idea about how to solve this 'problem'. I think
this
> > can be of very big consequence to NI as more and more conventional
apparatus
> > are 'build' by LabView.
> >
> > Thanx
>
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Message 3 of 6
(3,088 Views)
Ronald wrote:

> Mmm, idea!
>
> Why isn't anyone from NI responding?
>

Not sure why you would expect them to. What we are talking about here is
revision control and
following procedures. There are any number of ways to keep someone from
changing a VI.
Password protect, remove diagram, build it into an application.
As far as revision number and revision control, as long as none of the above
are done then
it makes no difference. That said there are a good number of revision control
systems (RCS)
that prevent unautorized persons from getting editable copies of VIs.
As far as auditors as concerned, if you follow your procedures then they have
little cause
to question your results.
Another option is to have the calibration lab (if you have one) certify the
number (10.2206) and
simply put it into the test procedure and make it an input on the front panel.
There has to be a certain amount of trust between you and the auditor.
Just my opinion
Kevin Kent

>
> Timothy John Streeter schreef in berichtnieuws
> 39FDDFCA.FB16A9AE@tait.co.nz...
> > Hi Boozz
> >
> > You could password protect your VI.
> >
> > Maybe you could have a calibration program, that only authorized users can
> have access, that saves the calibration data to a file
> > for test system to read and also generates a logged history of the
> changes.
> >
> > Tim
> >
> > Boozz wrote:
> >
> > > Hi,
> > >
> > > Some days ago I made a vi (calculating the mean current from a machine
> over
> > > 10 secs.) and this instrument is used for a withness test. Of course,
> once
> > > this vi is made I can change the appearance of it by using for example
> other
> > > constant values etc.
> > >
> > > How can I be sure that this instrument is accepted by an auditor (or
> > > notified body)?
> > >
> > > I looked at the vi-properties and noticed that every time I change
> something
> > > in the vi (and of course save the whole thing), the revision history is
> > > changed by LabView. Is this a solid way of proof that nothing in the vi
> has
> > > changed?
> > >
> > > Maybe this helps in explaning my problem:
> > >
> > > I use a transducer that gives a current of 0..20 mA linear to a the
> actual
> > > current of 0..50A. I use the resistor from NI (249 Ohms, so the current
> will
> > > be transformed to 0..5 Volts). For recalculation we found out that the
> > > measured voltage should be multiplied with 10.2206. In this case the
> system
> > > (transducer, shunt and DAQ-board) acts as a 0.5% class measuring
> instrument.
> > > We also calibrated this system.
> > >
> > > If I want to cheat on the measurement (for whatever reason it may be) I
> can
> > > simply change the 10.2206 into another value. It's even possible to do
> it
> > > without having the current revision number changed. (backup the revision
> > > before the one changed and voila)
> > >
> > > This means: problem with my auditor.
> > >
> > > Does anyone have any idea about how to solve this 'problem'. I think
> this
> > > can be of very big consequence to NI as more and more conventional
> apparatus
> > > are 'build' by LabView.
> > >
> > > Thanx
> >
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Message 4 of 6
(3,088 Views)
Kevin,

I think the last sentence is the truth: "There has to be a certain amount of
trust between you and the auditor."

What I did was what you wrote: We've asked a calibration lab to certify the
number. The difference is that I put it in another vi in which the measured
data is simply multiplied with this number.

In the sentence "Why isn't anyone from NI responding" I meant: This could
give lots of users a lot of problems in the future. What's the opinion of NI
in this...


Ronald

Kevin B. Kent schreef in berichtnieuws
39FE487F.6CDCBDC@mail.usa.alcatel.com...
> Ronald wrote:
>
> > Mmm, idea!
> >
> > Why isn't anyone from NI responding?
> >
>
> Not sure why you would expect them to. What we are talking about here is
> revision control and
> following procedures. There are any number of ways to keep someone from
> changing a VI.
> Password protect, remove diagram, build it into an application.
> As far as revision number and revision control, as long as none of the
above
> are done then
> it makes no difference. That said there are a good number of revision
control
> systems (RCS)
> that prevent unautorized persons from getting editable copies of VIs.
> As far as auditors as concerned, if you follow your procedures then they
have
> little cause
> to question your results.
> Another option is to have the calibration lab (if you have one) certify
the
> number (10.2206) and
> simply put it into the test procedure and make it an input on the front
panel.
> There has to be a certain amount of trust between you and the auditor.
> Just my opinion
> Kevin Kent
>
> >
> > Timothy John Streeter schreef in berichtnieuws
> > 39FDDFCA.FB16A9AE@tait.co.nz...
> > > Hi Boozz
> > >
> > > You could password protect your VI.
> > >
> > > Maybe you could have a calibration program, that only authorized users
can
> > have access, that saves the calibration data to a file
> > > for test system to read and also generates a logged history of the
> > changes.
> > >
> > > Tim
> > >
> > > Boozz wrote:
> > >
> > > > Hi,
> > > >
> > > > Some days ago I made a vi (calculating the mean current from a
machine
> > over
> > > > 10 secs.) and this instrument is used for a withness test. Of
course,
> > once
> > > > this vi is made I can change the appearance of it by using for
example
> > other
> > > > constant values etc.
> > > >
> > > > How can I be sure that this instrument is accepted by an auditor (or
> > > > notified body)?
> > > >
> > > > I looked at the vi-properties and noticed that every time I change
> > something
> > > > in the vi (and of course save the whole thing), the revision history
is
> > > > changed by LabView. Is this a solid way of proof that nothing in the
vi
> > has
> > > > changed?
> > > >
> > > > Maybe this helps in explaning my problem:
> > > >
> > > > I use a transducer that gives a current of 0..20 mA linear to a the
> > actual
> > > > current of 0..50A. I use the resistor from NI (249 Ohms, so the
current
> > will
> > > > be transformed to 0..5 Volts). For recalculation we found out that
the
> > > > measured voltage should be multiplied with 10.2206. In this case the
> > system
> > > > (transducer, shunt and DAQ-board) acts as a 0.5% class measuring
> > instrument.
> > > > We also calibrated this system.
> > > >
> > > > If I want to cheat on the measurement (for whatever reason it may
be) I
> > can
> > > > simply change the 10.2206 into another value. It's even possible to
do
> > it
> > > > without having the current revision number changed. (backup the
revision
> > > > before the one changed and voila)
> > > >
> > > > This means: problem with my auditor.
> > > >
> > > > Does anyone have any idea about how to solve this 'problem'. I think
> > this
> > > > can be of very big consequence to NI as more and more conventional
> > apparatus
> > > > are 'build' by LabView.
> > > >
> > > > Thanx
> > >
>
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Message 5 of 6
(3,088 Views)
If you buy LabVIEW Professional, you get the "Professiional G Developers Tools
Reference Manual". In there, you will a brief chapter on Quality standards
such as ISO and some ideas for configuration management and testing guidelines.
I suspect that this is as much an official opinion you're liable to get from
NI.

"Ronald" wrote:
>Kevin,>>I think the last sentence is the truth: "There has to be a certain
amount of>trust between you and the auditor.">>What I did was what you wrote:
We've asked a calibration lab to certify the>number. The difference is that
I put it in another vi in which the measured>data is simply multiplied with
this number.>>In the sentence "Why isn't anyone from NI responding" I meant:
This could>give lots of users a lot of problems in the future. What's the
opinion of NI>in this...>>>Ronald>>Kevin B. Kent
schreef in berichtnieuws>39FE487F.6CDCBDC@mail.usa.alcatel.com...>> Ronald
wrote:>>>> > Mmm, idea!>> >>> > Why isn't anyone from NI responding?>> >>>>>
Not sure why you would expect them to. What we are talking about here is>>
revision control and>> following procedures. There are any number of ways
to keep someone from>> changing a VI.>> Password protect, remove diagram,
build it into an application.>> As far as revision number and revision control,
as long as none of the>above>> are done then>> it makes no difference. That
said there are a good number of revision>control>> systems (RCS)>> that prevent
unautorized persons from getting editable copies of VIs.>> As far as auditors
as concerned, if you follow your procedures then they>have>> little cause>>
to question your results.>> Another option is to have the calibration lab
(if you have one) certify>the>> number (10.2206) and>> simply put it into
the test procedure and make it an input on the front>panel.>> There has to
be a certain amount of trust between you and the auditor.>> Just my opinion>>
Kevin Kent>>>> >>> > Timothy John Streeter schreef
in berichtnieuws>> > 39FDDFCA.FB16A9AE@tait.co.nz...>> > > Hi Boozz>> > >>>
> > You could password protect your VI.>> > >>> > > Maybe you could have
a calibration program, that only authorized users>can>> > have access, that
saves the calibration data to a file>> > > for test system to read and also
generates a logged history of the>> > changes.>> > >>> > > Tim>> > >>> >
> Boozz wrote:>> > >>> > > > Hi,>> > > >>> > > > Some days ago I made a vi
(calculating the mean current from a>machine>> > over>> > > > 10 secs.) and
this instrument is used for a withness test. Of>course,>> > once>> > > >
this vi is made I can change the appearance of it by using for>example>>
> other>> > > > constant values etc.>> > > >>> > > > How can I be sure that
this instrument is accepted by an auditor (or>> > > > notified body)?>> >
> >>> > > > I looked at the vi-properties and noticed that every time I change>>
> something>> > > > in the vi (and of course save the whole thing), the revision
history>is>> > > > changed by LabView. Is this a solid way of proof that
nothing in the>vi>> > has>> > > > changed?>> > > >>> > > > Maybe this helps
in explaning my problem:>> > > >>> > > > I use a transducer that gives a
current of 0..20 mA linear to a the>> > actual>> > > > current of 0..50A.
I use the resistor from NI (249 Ohms, so the>current>> > will>> > > > be
transformed to 0..5 Volts). For recalculation we found out that>the>> > >
> measured voltage should be multiplied with 10.2206. In this case the>>
> system>> > > > (transducer, shunt and DAQ-board) acts as a 0.5% class measuring>>
> instrument.>> > > > We also calibrated this system.>> > > >>> > > > If
I want to cheat on the measurement (for whatever reason it may>be) I>> >
can>> > > > simply change the 10.2206 into another value. It's even possible
to>do>> > it>> > > > without having the current revision number changed.
(backup the>revision>> > > > before the one changed and voila)>> > > >>>
> > > This means: problem with my auditor.>> > > >>> > > > Does anyone have
any idea about how to solve this 'problem'. I think>> > this>> > > > can
be of very big consequence to NI as more and more conventional>> > apparatus>>
> > > are 'build' by LabView.>> > > >>> > > > Thanx>> > >>>>>
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Message 6 of 6
(3,088 Views)