7835
Hydrazine Monitor
4 Electrical Installation
12
IM/7835–EN Rev. P
4.7 Sensor Unit – Sample Requirements
4.8 Sensor Unit – External Pipe Connections
Ensure the sample temperature and pressure are suitable for
measurement – see Section 11, page 28. If necessary, use
sample cooling and pressure-reducing equipment.
If particulate matter is present, such as oxides of iron, an in-line
filter is essential – see Section 9, page 21.
4.8.1 Inlet Pipe
Connect sample to the sensor unit using suitable de-scaled
stainless steel tube, 6.3 mm (0.25 in.) OD. Connect this tube to
the sample inlet coupling on the right-hand side of the panel via
the grommet in the base of the case.
The inlet tubing must have sufficient wall thickness to withstand
the highest sample pressure and the pipe lengths must be kept
short. Bend the inlet pipe to a right-angle outside the case to
allow removal of the liquid handling panel when required.
An isolator valve (not supplied) is necessary in the sample inlet
line to the sensor unit.
4.8.2 Drain Pipe
The drain from the split tundish at the bottom of the sensor unit
case consists of two stub pipe connections suitable for 10 mm
(0.4 in.) bore plastic or rubber tubing. Clean water waste can be
taken from one connection (and NaOH dosed waste from the
other connection can be used for pH checking) grab sample
collection or can be directed to a contaminated-water drain.
Warning.
The maximum pressures and temperatures
specified must not be exceeded. Where pressure-reducing
equipment is used, install a pressure relief valve between
this and the sample inlet to the monitor.
