GMI GDUnet, Руководство пользователя

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INTRODUCTION
1-3
(c) The GDU net as a gas delivery unit in standalone mode.
Test and calibration files are transferred from a PC / Laptop
running flexiCal net software, to the GDU
net
via a USB
memory stick.
Test and calibration results stored on the GDU net are
retrieved from the GDU net using a USB memory stick.
The setup consists of a GDUnet, gases and flexiCal net
software.
Note: For standalone operation refer to Chapter 7. A
large amount of the information contained in this
handbook is irrelevant when using standalone mode.
1.2 CALIBRATION GASES
The GDU net is connected to cylinders of calibration gas to ensure
that a consistent standard can be maintained against which the
instrument can be checked.
The GDU
net can connect up to 8 gas cylinders (a 4 gas cylinder
version is also available).
1.2.1 Recommended Types
The instrument should be calibrated in the gas it will be used in,
rather than using calibration factors, i.e. Propane instruments
should be calibrated with Propane gas etc.
Gases should be full scale or mid range of scale rather then
lower end; i.e. calibrate 100% LEL range at 50% LEL rather
than 10% LEL.
Heavier hydrocarbon gases may take longer to clear the system
than lighter ones like Methane, and should be carefully organised
in terms of location on the manifold position and test sequence.
1.2.2 Traceability
Gases should be analysed and traceable to National Standard.
The Test Certificate should have the total gas analysis including
air components.