MIL-HDBK-1005/16
11.6.2.5 Controls and Power Subsystem. The following are
desired power and control features that may be necessary
depending upon whether the sampler is to be a portable or
permanent installation:
a)
Capability for either alternating current (AC)
(electrically grounded system) or direct current (DC) operation.
b)
Battery life for 2 to 3 days of reliable hourly
sampling without recharging.
c)
Battery weight of less than 20 pounds (9 kg).
Batteries should be sealed so no leakage occurs.
d)
Solid-state logic and printed circuit boards.
e)
Timing and control systems contained in a
waterproof compartment and protected from humidity. Timer should
use solid-state logic and a crystal controlled oscillator.
f)
Controls directly linked to a flowmeter to allow
both flow-proportional sampling and periodic sampling at an
adjustable interval from 10 minutes to 4 hours.
g)
Capability of multiplexing, that is, drawing more
than one sample into a discrete sample bottle to allow a small
composite over a short interval. Also capability for filling
more than one bottle with the same aliquot for addition of
different preservatives.
h)
Capability of adjusting sample size and ease in
doing so.
11.6.2.6 General Desirable Features. For safety, maintenance,
reliability, and security in field applications, the following
general features are desired in an automatic sampler:
a)
Water-tight casing to withstand total immersion
and high humidity
b)
Vandal-proof casing with provisions for locking
c)
A secure harness or mounting device if sampler is
placed in a sewer
d)
Explosion-proof construction
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