Detcon TP-700 - Manual (Page 31)

Model TP-700
TP-700 Instruction Manual Rev. 3.5 Page 27 of 38
5. Service and Maintenance
5.1 Calibration Frequency
In most applications, monthly to quarterly span calibration intervals will assure reliable detection. However,
industrial environments differ. Upon initial installation and commissioning, close frequency tests should be
performed, weekly to monthly.
Test results should be recorded and reviewed to determine a suitable
calibration interval. If, after 180 days, an AutoSpan Calibration is not performed, the ITM will generate an
AutoSpan Fault.
5.2 Visual Inspection
The Sensor should be inspected annually. Inspect for signs of corrosion, pitting, and water damage. During
visual inspection, the Splash Guard should be inspected to insure that it is not blocked. Examine the porous
316SS flame arrestor within the sensor’s bottom housing for signs of physical blockage or severe corrosion.
Also, inspect inside the Junction Box for signs of water accumulation or Terminal Block corrosion.
5.3 Condensation Prevention Packet
A moisture condensation packet should be installed in every explosion proof Junction Box. The moisture
condensation prevention packet will prevent the internal volume of the J-Box from condensing and
accumulating moisture due to day-night humidity changes. This packet provides a critical function and should
be replaced annually. Detcon’s PN is 960-202200-000.
NOTE: A desiccant cap with a desiccant packet is attached to the sensor cell housing to avoid
damage during storage and shipping. This prevents water from contacting the sensor film, and
as a result helps to retain the stability of the factory span calibration.
NOTE: Store the desiccant caps with the desiccant packets in a sealed container (i.e. zip-lock
bag) for future use. It is advisable (but not mandatory) to reinstall the desiccant cap and packet
during prolonged periods without power (more than 1 day is considered “prolonged”). An
active desiccant packet is blue in color and turns pink when consumed. (P/N 960-399800-000
Package of 10)
5.4 Replacement of Plug-in H
2
S Sensor
O-Rings
Splash Guard
Adapter
Plug-in Replaceable
H2S Sensor
Lens and LED
Display Interconnect
Wires
Housing Bottom
Locking Set-Screw Intelligent Transmitter Module (ITM)
Micro-processor controlled circuit
encapsulated in an Explosion proof
housing.
Magnetic
Programming
Switches
M
O
D
E
L
T
P
-7
0
0
d e
tc
o
n
in
c
.
H
2 S
S
e
n
s o
r
SplashGuard
Figure 12 Sensor Assembly