COSA Xentaur Xentaur LPDT - Manual (Page 22)

Section 3: Instrument
page 15
(and pressure if installed) can be read.
In the digital mode multiple units can operate on
the same loop cable as a multi-channel instrument.
Alarms:..............................The 4-20mA signal or the digital output may be used
by an external device to operate relays.
Isolation: ...........................Sensor and case are isolated from the current loop
but are shunted with a 33V transorb and 2000pF
capacitor.
3.3 Installation
3.3.1 Mechanical Installation
The LPDT has two thread sizes for mounting to the sample
cavity (consult the sensor installation section) where the
dewpoint will be measured. Various adapters are available
for direct connection into existing system openings. Ask
your representative for a Sample Cell, if you do not have the
ability to provide an appropriate sample cavity mounting. If
the ¾”x16 thread is used then the LPDT will seal against the
wall of the sample cell with the provided Viton A O-ring. If
the 14mm x 1.25 spark plug thread is used then an addi-
tional Viton gasket must be installed to provide the proper
seal. Ask your representative for this gasket, it is available
free of charge. The LPDT is light enough such that either
thread will mechanically support the whole instrument. To
prevent any leaks, tighten the LPDT into the sample cavity,
with a
1 7 /
8
” wrench, 1/8 turn past finger-tight to assure
metal-to-metal contact.
Since the tightened positioning of the LPDT is unpredict-
able, its front panel may be rotated (360°) to allow easy
reading of the display. Press down gently on the spring
loaded face plate and turn it to the desired position.
The sensor can be removed from the LPDT by unscrewing
it. Make sure that the sensor is securely fastened to the