HF scientific MicroTUV Online UV %Transmission Sensor/Sampler (large) - Manual (Page 12)

TUV (04/03) Page 4
REV. 0.6
2.4.2 Pipe Insulation Installation
Pull the intake and drain lines out and lay them together with the heating cable (which should have already
been installed) as straight as possible. Slide the enclosure interface over all three lines up to the bulkhead
panel with the larger opening upward (see Figure 7). Using the 15-inch cable tie, cinch the interface around
the three bulkheads tightly. The insulation lenghts and the couplers are slit lenghtwise to allow assembly over
the lines, instead of running the lines through the insulation. Wrap a 6-foot length around the lines and cable
and slide it up to the interface.
Peel the backing tape from both sides of the slit and press together. Apply adhesive to the outside of the last
two inches on the end close to the interface. Slide the length into the interface no more than two inches while
twisting it to spread the adhesive evenly. Make sure that the intake and drain lines are not kinked. Wrap
another 6-foot length around the lines and cable and slide it up to the first length.
Peel the backing tape from both sides of the slit and press together. Apply some adhesive where the two pieces
butt together, then press and hold the joint until a bond is formed. The 8 inch sections of insulation are
designed to act as couplings between the 6 foot lengths. After the butt joint is bonded, apply more adhesive
around the joint not more than 4 inches in either direction. Take an 8-inch coupling and wrap it around the
joint, making sure it is centered. Peel the backing tape from both sides of the slit and press together. Hold
until the applied adhesive begins to set up. Repeat this process down to the end of the line. Cut off any excess
insulation 6 inches (150mm) above the intake filter. It is recommended that the insulated lines be run through
PVC pipe for extra protection and that any bends are very gradual to avoid kinks in the lines.
3.0 STEP-BY-STEP OPERATION
3.1 THEORY OF OPERATION
T he HF scientific On-line UV Transmission Sensor/Sampler is intended to operate along with a controller
or analyzer to comprise a complete "system". The TUV Sensor/Sampler can perform all of it's own
internal control functions, but it has no form of input or output. The Sensor/Sampler communicates
to the controller or analyzer through an RS-485 data port. It is the controller or analyzer's job to ask
for readings and interpret them. The controller or analyzer is also responsible for initiating
calibrations, displaying data and supporting control functions. Please refer to the manuals accompa-
nying the controller or analyzer for complete information of its operation.
The HF scientific On-line UV Transmission Sensor/Sampler is specifically designed to monitor the
transmission of 253.7nm light through fluid being pumped through the sensor cuvette. The low-pressure
mercury vapor lamp is temperature controlled by the Sensor/Sampler’s microprocessor, which turns the
lamp to the “on” state for a fraction of a second every 30 seconds. During this short interval several hundred
readings of the transmission are taken. These readings are digitally signal processed over the "on" time
period to preclude instantaneous fluctuations from biasing the value. Because the lamp is "on" for such
a short period, UV degradation of the optical path is held to an absolute minimum.
The Sensor/Sampler enclosure houses the sampling pump, control valve and a one gallon empty container
for the 100% transmission calibration fluid. The amount of calibration fluid is sufficient for approximately
15 calibrations, and is contained in a replaceable container. The calibration fluid is available as a
replacement item. The entire pump-head kit is replaceable and is available as Part No. 22041. The Sensor/
Sampler also houses the Sensor module, CPU module, Power Supply module, cabinet heater, T-strainer,
and flow sensor. Refer to Section 7.3 for replacement part numbers.
The CPU module controls the lamp heat, serial port communication system, and many other housekeeping
functions. A signal from the flow sensor will shut the unit down if insufficient flow is detected for more
that 10 seconds. This safeguard will prevent a buildup of pressure if a line were to get clogged or excessive
leakage if a line or connector were to fail.