Servomex 07931001B, Operator'S Manual

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07931001B revision 6 © Servomex Group Limited. 2020
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6.13 Automatic In-Situ Validation
The Laser 3 Plus includes the ability to run an automated version of the in-situ
validation described in the previous section.
The automated version of in-situ validation is controlled entirely by Modbus. There is
no user interaction via the user interface. It is designed for remote operation via a
customer interface such as an HMI (Human Machine Interface).
Auto Validation is performed collaboratively between the Laser 3 Plus and the HMI.
The main reason why the HMI needs to play a role in auto validation is that the
Laser 3 Plus does not have the ability to control external gas valves. This will need
to be done by the HMI under the direction of the Laser 3 Plus to control the flow of
zero and span-gases into the validation cell.
This means that auto validation can only be performed on a system that has been
specifically configured to do so and which includes a suitable HMI plus all necessary
pipework and valves.
Note that a separate document has been produced by Servomex which provides
guidelines and assistance for a third party wishing to produce a HMI capable of
collaborating with the Laser 3 Plus to perform auto validation. It has the document
No 07900C039 and is available on request.
Safety Warning When Performing Auto Validation
It is extremely important before running auto validation to verify the correct operation
of the following:
•
All pipework, valve blocks, flow meters etc. are connected correctly with no
leaks or damage.
•
Zero and span-gases are able to flow into the validation cell when
commanded.
Failure to adhere to this may result in auto validation producing an incorrect result. It
may also result in the Laser 3 Plus producing an incorrect measurement when it
exits auto validation and returns to normal operation.
System Configuration For Auto Validation
The diagram below shows a simple functional view of a Laser 3 Plus setup on
process with an in-line validation cell attached ready to perform auto validation.