thuba PS 830, Руководство пользователя

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Manual BVS 19 ATEX E 080 X 19
Edition March 2020 thuba Ltd., CH-4002 Basel
Copyright Switzerland
Figure 1 Block diagram
3.2 Purging period
3.2.1 Pressurized enclosure system without
pre-purging
If the operator is sure, that the atmosphere inside
of the enclosure and the appropriate pipe infras-
tructure is below 25% of the lower explosive limit
(LEL) (IEC 60079-14 chapter 13.4) at power up,
he can abandon the pre purging of the enclosure
in zone 2. In that case the PS 830 monitors only
the pressure inside of the enclosure on 0.8 mbar
at minimum and maximal 22.0 at maximum. If
any limit is exceed, the PS 830 changes the
state on relay(s) output(s).
The purge medium flows through an adjustable
sinter metal throttle into the housing while reduc-
ing its pressure (see block diagram). The LA 830
has an mechanical output valve which opens at
approximately 5 mbar to let the purge medium
out. Before this valve is a spark lattice located
thus the purge medium can be exhausted direct-
ly to the hazardous area.
Control unit PS830