
Pulse Instruments POA08 Manual
Version 1.1
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4.2 Manifold.Overview
Sample Inlet – The sample inlet is the start of the sensor manifold. A sample should
be fed through the manifold inlet from a dedicated sampling pump, or off the pressure
side of a recirculation pump.
Ball Valve – Allows or stops the sample from flowing through the manifold. Close the
valve when servicing the sensor or manifold.
Flow Cell – The flow cell houses the sensor and spray assembly in place. The top of
the flow cell has a ¾” FNPT opening for the ppm sensor to screw into.
PPM Sensor – Use PTFE tape on the ¾” threads prior to screwing it into the flow cell
for a good seal. Once the sensor is secured, measure the length of cable that will be
needed for the sensor to be wired into the transmitter terminal block. See section 4.3.
If the excess cable is desired to be cut off, be sure to leave some slack. Ensure that
the spray nozzle does not come into direct contact with the ppm sensor tip, this can
damage the sensor.
Solenoid and Pressure Switch Box – This enclosure houses the solenoid used for the
sensor spray and the pressure switch. The enclosure has two sets of cables that
need to be wired into the control panel. The first set (3-wire power cord) is for the
solenoid and must be wired into terminals 4 through 6 (see Section 4.3). The second
cable is a two-wire shielded cable for the power switch which must be wired into
terminals 7 through 8 (see Section 4.3).
Flow Meter – Provides a visual indication of the approximate flow rate going through
the manifold. For best results the flow rate must be consistent at approximately 1
gallon per minute. A slightly lower or higher flow rate also works as long as the flow
rate remains the same at all times.
Spray Nozzle – The spray nozzle is installed in the flow cell to spray a water jet
across the sensor surface at user defined intervals. The depth of the spray nozzle
can be adjusted if necessary by loosening the compression fitting. The spray nozzle
is pre-connected to the solenoid. Ensure that the spray nozzle does not come into
direct contact with the ppm sensor tip, this can damage the sensor.
Water Source for Spray Nozzle – The ¼” tubing coming out of the Solenoid and
Pressure Switch Box provides must be connected to a pressurized water source in
order to provide the spray nozzle with water to spray the sensor surface with.
Sample Inlet
Ball Valve
ppm Sensor
Spray Nozzle
Flow Cell
Sampling Port
Water Source for
Spray Nozzle
Solenoid and
Pressure Switch Box
Flow Meter
Sample Outlet