CO2 Incubators > TC to IR Conversion Kit  »   How do I convert my TC sensor to an IR sensor?

Step 1.
Turn off and unplug the unit. Do not work on the unit while there is power going to it.

Step 2.
Using a medium Phillips head screw driver, remove the top access cover by removing the 6 screws holding it in place. This will expose the control area. Set the top cover and screws aside until the conversion is complete.

Step 3.
a.    Locate tube heater wires and disconnect them from the wire nuts. Keep the wire nuts on the other wires but remember that you will be connecting the new tube heater here later.
b.    Locate the copper sample tube and disconnect the black polyvinyl tube. The easiest way is to snip it off as close to the brass fitting as possible using wire cutters or scissors. You will be attaching this tube to the fitting on the new assembly.
c.    Locate the black polyvinyl tube attached to the other end of the injection tube and disconnect it. Pull the injection tube out of the clamp on this end
d.    Locate the rubber lab stop. Insert the flat edge of a small screwdriver between the side of the lab stop and the edge of the hole and pry the lab stop up and out. There are slot cut into the sides of the lab stop so it will separate from the tubes and sensor cable.
e.    Locate the TC Interface board and disconnect the following: The grey sensor cable, the signal wire from CH 3 on the main control board and the black and white power wires from the main terminal block. Once these are removed, use a small Phillips screwdriver to remove the TC Interface board. Follow the grey sensor cable from the TC interface board to the rubber lab stop and carefully snip the wire ties so you can isolate the cable.

Step 4.
a.    Remove the chamber top duct to reveal the TC sensor.
b.    Using a 5/16 nut driver, remove (and set aside for future use) the 4 cap nuts and washers. This will allow the TC sensor to hang down by its cable.
c.    From the control area, stick the nut driver down through the hole from which you removed the upper lab stop and push down to remove the lower lab stop. Bend the copper injection tube up to allow it to go down through the hole. Pull the tube assembly, sample tube and sensor cable down into the chamber and out of the unit. Once this is completed, the entire TC sensor and injection assembly will have been removed from the unit.

Step 5.    Installing the IR Sensor and Injection tubing.
The IR sensor, injection tube and sample tube are attached to a copper mounting plate and the copper mounting plate is attached to the top of the chamber using the 4 cap nuts and washer that were removed in Step 4 b.
a.    Bend the copper injection tube up so that it and all the wires can be pushed up through the hole in the top of the chamber and the mounting plate fastened to the top of the chamber using the 4 cap nuts and washers. Note: The plate is sealed to the chamber ceiling by the Permagum as is the sensor sealed to the plate.
b.    From the top of the unit. Carefully bend the copper injection tube back into position and into the clamp. Re-attach the black polyvinyl tube to the brass fitting. The best way to do this is to hold the brass fitting in one hand and the black tubing in the other and apply pressure while wiggling the black tubing back and forth until it has bottomed out against the fitting.
c.    Repeat this process with the sample tube.
d.    Connect the tube heater element wires to the 2 wire nuts and tape the wire nuts.
e.    Run the wires from the sensor back along the place where you removed the TC sensor cable (use wire ties to hold them in place) and attach them as follows: The black and white wires with the 2 pin connector are plugged into CH 3 on the main control board (where you unplugged the TC signal wire). Unplug the red 4 pin connector from the 12 VDC power supply and cut the wires from the connector. Discard the connector. Plug the new 4 pin connector in its place. Strip the insulation back from the red and black wires you cut from the old connector and attach them to the red and black leads from the new connector using the butt connectors supplied.
f.    Check your work.
g.    Check your work again.

Plug the unit in and turn it on. The CO2 display should read very close to 0.1 and if it does not use the panel buttons to make it say 0.1. Allow the chamber to stabilize at set temperature and it is ready to go.