Detcon IR-700 - Replacement of ITM

Model IR-700
IR-700 Instruction Manual Rev. 4.3 Page 33 of 46
a) Remove power to IR-700 sensor by lifting the + 24 VDC wire in J-Box.
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 IR combustible gas sensor 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.
e) Thread the Bottom Housing onto the ITM to a snug fit and tighten the locking setscrew using the M1.5
Allen wrench. Reinstall the splashguard.
f) With the new IR plug-in sensor physically installed, two functions are required to be performed:
1) Perform the Set Sensor Gain function to match the new sensor with the ITM (Section 3.5.6).
2) Perform a successful AutoZero and AutoSpan to match the new sensor with the ITM (Section 3.4).
5.5 Replacement of ITM
Caution: Hazardous areas must be declassified before opening the junction box or
removing and replacing the ITM
a) Disconnect all sensor wire connections at the J-Box after removing power source.
b) Use a wrench and loosen the locking nut at the top of the ITM and unthread the ITM from the junction
box.
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 pull the plug-in IR combustible gas sensor out of the ITM and set it aside along with the bottom
housing and splashguard. 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 13).
h) Two functions are required to be performed on the new ITM:
i) Perform the Set Sensor Gain function to match the new sensor with the ITM (Section 3.5.6).
ii) Perform a successful AutoZero and AutoSpan to match the new sensor with the ITM (Section 3.4).