Fast Purge Switch - Siemens Maxum II Manual

2.2.3

Fast Purge Switch

The fast purge control switch, which is shown in the following figure, is located inside the
detector enclosure (middle door) or near the purge air regulator as shown in the figure below.
This switch is operated by the user and is used to re-purge the electronics enclosure for a
period of 8 minutes after the sealed enclosure has been opened and then re-sealed.
The fast purge function moves a large volume of air through the sealed analyzer within the 8
minutes. This is to ensure that positive purge pressure is reached and to allow any possible
flammable vapors or gases to be removed from the enclosure. After the 8 minute fast purge
time, the switch should be turned off (to the right) so that normal purge air flow can resume.
The fast purge switch is connected to the Purge Control Module manifold (described below)
to allow air to flow directly into the electronics enclosure. When air is flowing through the fast
purge switch, the higher flow should be audible.
One of two new labels, one for each hazard zone, is now applied to the cabinet around the
fast purge switch. These are indicated in the figure below.
Explosion Protection Safety Standards
Manual, August 2017, A5E02220442001 Rev 8
2.2 Electronics Purging System (without Automatic Purge Unit)
Safety Systems - Purging
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