Temperature Controller Instructions

Using the variable temperature accessory.

1) Follow the initial steps of initial steps of sample preparation, logging on, locking and shimming, that are used for a routine proton experiment.

2) Turn on the N2 tank behind you (as you are sitting at the computer). Open the valve on top of the tank; do not adjust the regulator.

3) Change the gas supply to the NMR from house air to tank N2. Go to the air handler to the left of the door to the NMR magnet room. On the far left, there are two valves approx. 5' and 6' high. Turn the upper one to vertical (open) and the lower one to horizontal (closed), in that order.

4) If you will be going below room temperature, you will need the heat exchanger dewar filled with liquid nitrogen. This is a safety goggles procedure! The dewar is the white dewar next to the NMR magnet. If the dewar is not filled, fill it or get someone else to fill it. Carefully disconnect the gas line from the heat exchanger to the NMR (there's a clip under the probe). Insert the heat exchanger into the dewar (it may spit some liquid nitrogen), then reconnect the air line to the probe.

5) You should be running the NMR acquisition program. If not, start it now. Display the temperature window by selecting

          Temperature monitor

You may move the window to any convenient location on the screen.

6) Set the temperature. First, you will need to enter the desired temperature, then set it. Enter the temperature by selecting

          Temperature control
              Enter temperature TE

Enter the desired temperature in kelvin, then press return. Set the temperature by selecting

          Temperature control
              Set temperature

7) Open the NMR console. About 1/2 way up from the bottom is the temperature controller (labelled BDTC, with a pressure guage and temperature readout). Depress the "heater on" switch so that it lights up.

8) When you are finished, turn off the heater on switch on the temperature controller. Remove the heat exchanger from the dewar (if there is liquid nitrogen in the dewar) and switch the gas flow back to house air. Turn the nitrogen tank valve off.