Site Requirements
Computer and Communications
Thermo Fisher Scientific
Prima PRO & Sentinel PRO Mass Spectrometers User Guide
3-3
Warning!
On Ex systems, connection is made to an equivalent set
of terminals in the flameproof box above the instrument enclosure.
A number of serial formats are possible:
a.
RS232 simple 3-wire link, transmission distance 5 meters.
May be extended by the use of good quality screened cable.
b.
RS422 4-wire, full duplex link, extended transmission
distances. For the host link, this is likely to require an RS422-
232 converter for connection to the PC (available as an
option).
c.
RS485 2-wire, half duplex link, extended transmission
distances. Cannot be used for the host link.
The fibre optic communication option can be used to extend
transmission distances for the above communication formats by up to
1000 meters. When selected for any given link (there are five links
that can use fibre optic communication), a pair of fibre optic
converters is supplied. One is to be fitted in the instrument enclosure
and the other at the remote end, PC / DCS.
The interconnecting fibre optic cables (a pair of fibre cores for each
link) must:
a.
have ST terminations
b.
support multimode operation
c.
be compatible with LED drivers.
It is recommended that one or two spare fibre pairs are included in
multi-core cable runs to allow for future expansion.
It should be noted that selection, installation, and termination of the
fibre optic cable is a user / installer responsibility.
Warning!
Where fibre optic links are selected for use with a
hazardous area system the following additional requirements must be
met:
The remote fibre optic converter (i.e. not installed in the
purged instrument enclosure) must be located wholly within a
safe area or a suitably protected enclosure (e.g. Exd, Exp).
The fibre optic cable must have a suitable degree of
protection, e.g. steel wire armour or equivalent.
Fibre Optic
Communication
Hazardous Area
Systems
