Taking A Measurement; Sampling Information - Alpha Moisture Systems SADPmini Instruction Manual

6.1 Taking a Measurement

After purging the system to be monitored fit the SADPmini sample pipe to the sample
connection (6). Allow the gas to purge for a further 2 minutes with the head down.
SADPmini
Head Lowered
Restrict the outlet of the SADPmini (7) by placing a finger over the sample exhaust (9),
so that the pressure of the sample lifts the telescopic head. As soon as the head is fully
extended remove the finger, to prevent pressure build up. Pull gently on the head to make
sure it is fully extended. If there is not enough pressure to lift the head assembly, assist it
by pulling it up; do this very slowly so that ambient air is not drawn in through the outlet.
It may help to turn the head to break the "sticktion" be sure to turn clockwise, so as not
to loosen the locking ring.
The sensor will respond to the moisture level present in the sampled gas. The displayed
moisture value will continue to change until the sensor reaches equilibrium; at which
point the displayed value is representative of the moisture level in the sampled gas.
When the test is finished push down the telescopic head fully and carefully, turn off the
sample flow and disconnect the sample pipe. With the head in the down position the
desiccant will dry the sensor, ready for the next test.
NOTE - It is important that the head assembly is either fully up, or fully down to keep the
desiccant isolated from ambient air, so avoiding wetting it. When the SADPmini is not in use
it should be stored with the head in the down position.
7

Sampling Information

Refer to the sample system schematic in section 4.1.
The SADPmini sensor will respond to the water vapour pressure of a gas in contact
with it. It is important to ensure that the gas passing through the sensor head is the same
as the gas being sampled.
SADPmini
Head Raised
Page 6 of 33