Hazardous Area Operation
Other Hazardous Area Considerations
Thermo Fisher Scientific
Prima PRO & Sentinel PRO Mass Spectrometers User Guide
A-17
the system from a controller failure a pair of independent thermal
cutout switches (140°C) is fitted to the RMS body.
The inlet temperature alarm (GasWorks software interface) should be
monitored as this will give an indication that the thermal switches
have tripped. Also, the temperature will oscillate in the 120°C to
140°C region.
The enclosure temperature is monitored by the air conditioner, which
generates an alarm when the temperature is outside the control
window, and an independent temperature sensor, which triggers an
alarm at 40°C.
There are two batteries fitted within the instrument enclosure.
Table A
–7.
Battery types within the instrument enclosure
Processor Assembly
Lithium thionyl chloride (Li/SOCl
2
)
(Thermo Scientific supply) Type
½ AA
Nominal
capacity
1.2Ah
Nominal voltage
3.6V
Turbo Molecular Pump
Lithium manganese dioxide (Li/MnO
2
)
(3rd party supply)
Type
Coin cell
Nominal
capacity
48mAh
Nominal voltage
3V
Warning!
Neither of these batteries is likely to need replacement during
the lifetime of the instrument or pump respectively.
If a problem occurs, the complete assembly should be
replaced.
No attempt should be made to replace the batteries.
See also the Battery Warning label on the inside of the
instrument door.
All Prima PRO and Sentinel PRO systems have a dry gas vent
connection. Nitrogen (other inert dry gases could be used) is
connected to the vent port on the vacuum system (via a regulator).
When the vacuum system shuts down, it fills with the dry gas (rather
than ambient air). This facilitates a much faster subsequent pump
down.
For hazardous area systems, the dry gas vent has an additional
function. While the system is shut down it is possible for hazardous
Batteries
Dry Gas Vent
