Thermo Scientific Prima PRO, Руководство пользователя

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Hazardous Area Operation
Purge Operation
Thermo Fisher Scientific Prima PRO & Sentinel PRO Mass Spectrometers User Guide A-11
The sample containment system is that part of the sample gas
handling that runs inside the main enclosure and which therefore has
the potential to leak into the enclosure. Once the sample passes into
the vacuum system of the analyser, the pressure is sufficiently low
that a leak into the purged enclosure cannot occur. For a
Prima PRO Ex, the vacuum system can be considered as anywhere
downstream of (and including) the inlet transfer line. For a
Sentinel PRO Ex, it is anywhere after the membrane inlet.
Any joint or seal in the sample containment system is considered as a
potential source of internal release. It is necessary therefore to
identify and quantify these potential sources and to do this, the
maximum pressure within the sample containment system must be
defined (see below). This is governed by pressure in both the sample
and exhaust lines, and it is a user responsibility to maintain the value
below the defined maxima for the instrument.

Maximum pressure in sample containment system (maximum
pressure in sample inlets / exhaust) for Prima PRO Ex:
0.2 bar(g)*

Maximum pressure in sample containment system (maximum
pressure in sample inlets / exhaust) for Sentinel PRO Ex:
< 0.0 bar(g)†

Maximum leakage from sample containment system (Prima PRO
Ex): 0.25 Nl/min
Note:
*It is a user responsibility to maintain this pressure and ensure it is
not exceeded.
†Pressure is maintained by use of a sample vacuum pump. See
details below.
Prima PRO Ex
The sample containment system is limited to a sample loop contained
within the inlet stream selector, (RMS) valve, where physical joints
have been kept to an absolute minimum. The worst leak occurs if the
pressure transducer for the flow sensing fails mechanically or
becomes disconnected. This is the maximum leakage (0.25 Nl/min)
from sample containment system defined above.
Sample
Containment
System
Definition and
Description
Parameters
Leakage Handling