Turning Off The Pump; Pump Low Flow Alarm; Sample Draw Probe; Calibration - Sperian PHD6 Reference Manual

Remove the pump and press the MODE button to
resume diffusion operation.
3.2.2

Turning off the pump

To turn off the pump, simply remove the pump
from the bottom of the instrument. The screen
will show "Pump Fault" followed by "Pump
Disconnected". Press MODE to continue without
the pump.
→
3.2.3

Pump low flow alarm

The PHD6 Pump contains a pressure sensor that
continuously monitors for restrictions in airflow
caused by water or other fluids being drawn into
the unit and immediately acts to turn the pump off
in order to protect the sensors, pump, and other
PHD6 components from damage.
CAUTION: Never perform remote sampling
with the PHD6 without the sample probe
assembly. The sample probe handle contains
replaceable filters designed to block moisture
and remove particulate contaminants. If the
pump is operated without the probe assembly
in place, contaminants may cause damage to
the pump, sensors and internal components
of the PHD6
When the pump is active and
functioning properly, the moving
pump icon is shown on the lower
status bar on the display. Low
flow or other pump fault
conditions activate audible and visible alarms and
cause the display of the appropriate explanatory
message.
→
Press MODE once the blockage has been
cleared to restart the pump.
The pressure sensor in the sample draw pump is
designed to detect pressure changes while the
sample-draw probe is being held in a vertical
position. If the probe is held horizontally or at a
low angle while inserted into a fluid, a pressure
drop sufficient to cause the pump to shut down
may not be generated, and water could be drawn
into the pump assembly causing damage to the
pump, sensors and internal components of the
PHD6.
CAUTION: Insertion of the sample draw tube
into a fluid horizontally or at a low angle may
lead to water ingress and may cause damage
to the sensors and internal components of the
PHD6.
If the PHD6 determines that a significant increase
in pressure has occurred, it will go into alarm and
notify the user that there is a blockage of the
pump. The display will alternate between the
following two screens.
Remove the blockage and press the MODE
button to acknowledge the alarm and resume
sampling.
3.3

Sample draw probe

The PHD6's sample draw probe is the standard
probe assembly from Sperian. The sample probe
handle contains moisture barrier and particulate
filters designed to remove contaminants that
might otherwise harm the instrument.
Particulate contaminants are removed by means
of a cellulose filter. The hydrophobic filter
includes a Teflon™ barrier which blocks the flow
of moisture as well as any remaining particulate
contaminants.
Sample probe filters should be replaced
whenever visibly discolored due to contamination.
See section 6.5 for a probe diagram and a list
of available sample probe filter replacement
kits.
4.

Calibration

The accuracy of the PHD6 should be verified on
a regular basis. Verification can be as simple as
performing a bump test, which is described below
in section 4.1. If the instrument fails the fresh air
test, then it must be fresh air calibrated before
use. If the instrument fails the bump test with
calibration gas, it must be successfully span
calibrated before use.
Note: The NDIR-CO
cannot be zero calibrated in fresh air. For
specific instructions on calibrating the CO
sensor, proceed to section 4.4.
Note: The NDIR-CH
4
must be calibrated with methane calibration
scale to the actual amount of methane in the
cylinder in terms of percent volume methane.
See section 4.5 for details.
* The Canadian Standards
Association (CSA) requires combustible gas
sensors to be bump tested prior to each day's
use with calibration gas containing between
25% and 50% LEL. The functional (bump) test
procedure is covered in section 4.1.
**
Association (CSA) requires combustible gas
sensors to undergo calibration when the
17
sensor used in the PHD6
2
2
sensor used in the PHD6
The Canadian Standards