Campbell Scientific PVS4100/4120/4150 Portable Automatic Samplers - Manual (Page 32)

Section 3. Operation
3-2
Should the sampler, for any reason, not be able to draw a sufficient volume of
fluid to obtain a sample, the unit automatically initiates a second attempt.
Should a sample still not be delivered, the sequence will be abandoned and the
unit will await the next initiation. Upon two consecutive failures, the sampler
will suspend the sampling program until manually RESTARTed.
If programmed with the FAULT SHUTDOWN “disabled”, the sampler will
not make a second attempt to draw the sample, but will simply abandon it and
await the next sample initiation. Neither will the unit suspend the sampling
program after consecutive failures. This function is provided for use in the
event that the sample source may be lacking sufficient fluid from which to
draw, for a period of time , yet allows the sampler to continue operating
without a “FAULT SHUTDOWN” occurring. The second attempt is not made
to prevent unnecessary wear on the sampler.
3.1.2 Line Voltage Failure
Should the sampler have a factory installed internal battery or have an external
battery connected, the sampler will continue operating. The duration of
operation will depend on the capability and charge level of either battery. The
frequency and the length of each sample cycle will also have an impact on how
long the batteries will last.
3.2 Operating Instructions
3.2.1 Sample Volume Adjustment
Setting the desired sample volume is accomplished by adjusting the height of
the volume control tube within the metering chamber. The tube is mounted
through the top of the chamber with a gland nut fixing the position. To adjust
the sample volume, loosen the nut until the volume control tube may be moved
freely. Raise or lower the bottom end of the tube to the desired volume using
the lines provided on the side of the chamber as a guide (lines are spaced at 100
cc intervals with the exception of one at 50 cc). Tighten the gland nut to hold
the volume control tube at the desired position.