MAC MAC155H, Instruction Manual

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MAC155 Rev. 12 ©Copyright MAC Instruments 2005. All Rights Reserved.
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Make sure that the filter is in place before inserting the unit into the
mounting adapter.
Operating the MAC155 Probe without a filter can cause severe damage to the
unit which is not covered under the warranty.
The internal components of the MAC155 Probe are protected from particles
in the atmosphere being monitored by a 10 micron filter element. The filter
element is mounted under the filter cover at the end of the MAC155 Probe
barrel. Because of the large area of the filter (Approximately 9.5 square inches /
61cm
2
), and the low flow rate of the sample (approximately 3.3 cubic inches per
minute / 54cm
3
per minute), the filter can usually go a long time without cleaning.
In cases where high amounts of particles are present the automatic filter blow
back option should be used. This option automatically cleans the filter by
blowing user supplied compressed air in the reverse direction through the filter
once per day during the calibration check.
In order to minimize the time that the MAC155 Probe is out of service, it is
recommended that if the filter ever becomes clogged it be replaced with a new or
previously cleaned filter element. The dirty filter can then be cleaned and used
as a replacement the next time that the filter requires service.
The filter is a cylinder that is open at both ends. Dry particles such as ash
can be removed from the filter by blocking one end closed and blowing
compressed air into the other end while taking care not to breathe in the
particles or get them into the eyes.
If the filter is clogged by compounds that will not blow away but are
soluble in water, then the filter can be cleaned by soaking it in water and then
blowing away the water with compressed air as described above for particles.
The extension tube should also be blown out and cleaned.