Detcon TP-700 - Manual (Page 32)

Model TP-700
TP-700 Instruction Manual Rev. 3.5 Page 28 of 38
a) Remove power to TP-700 sensor by lifting the + 24VDC wire in J-Box.
NOTE: It is necessary to remove power while changing the plug-in H
2
S sensor in order to
maintain area classification.
b) Use a M1.5 Allen wrench to release the locking setscrew that locks the ITM and bottom housing together
(One turn will suffice - Do not remove setscrew completely).
c) Remove splashguard. Unthread and remove the Bottom Housing from the ITM.
d) Gently pull the plug-in H
2
S sensor cell out of the ITM. Orient the new plug in sensor so that it matches
with the female connector pins. It may be necessary to look from below to assure alignment is correct. When
properly aligned, press the sensor in firmly to make the proper connection.
NOTE: The previous plug-in H
2
S sensor cell did not use a Face seal o-ring design. If you are
installing this new face seal o-ring version to replace an older revision sensor, you must fully
remove the adhesive gasket from the inside of bottom housing first
e) Thread the Bottom Housing onto the ITM to a snug fit and tighten the locking setscrew using the 1/16”
Allen wrench. Reinstall the splashguard.
f) Perform “Set Heater Power (Section 3.5.6 to match the new sensor with the ITM.
g) Perform a successful AutoSpan to match the new sensor with the ITM (Section 3.4).
5.5 Replacement of ITM
a) Remove the power source from the sensor assembly. Disconnect all sensor wire connections at the J-Box
taking note of the wire connections.
NOTE: It is necessary to remove power to the J-Box while changing the ITM in order to
maintain area classification.
b) Use a wrench and the wrench flats provided at the top section of the ITM and unthread the ITM until it can
be removed.
c) Use a M1.5 Allen wrench to release the locking setscrew that locks the ITM and bottom housing together
(One turn will suffice - Do not remove setscrew completely).
d) Remove splashguard. Unthread and remove the Bottom Housing from the ITM.
e) Gently remove the plug-in H
2
S sensor from the old ITM and install it in the new ITM. Orient the plug-in
sensor so that it matches with the female connector pins on the new ITM and press the sensor in firmly to
make proper connection.
f) Thread the bottom housing onto the ITM until snug, tighten the locking setscrew and reconnect splashguard.
g) Feed the sensor assembly wires through the ¾” female NPT mounting hole and thread the assembly into the
J-box until tight and the ITM lens faces toward the front access point. Connect the sensor assembly wires
inside J-Box (Refer to Section 2.6, and Figure 8).