Old Gatan 626 cryo holder

The old holder, its transfer station and tool box are labeled with a yellow sticker. Only use the right set of tools with it.

warm up cycle

A warm-up cycle should be done after every cryoEM sesssion

1. Insert the holder in the Turbo pumping station and make sure that the valves V1 and V2 are open to allow pumping on the tip of the holder. Connect the cable of the heat controller to the holder. Important: Do not twist the cable while connecting

2. Rotate the holder, so that the opening of the dewar faces to the ground.

3. If the controller is off: Switch on the power of the heat controller on the backside. The front panel will indicate the current measured temperature of the holder.

4. Click on the dial on the outer left. This will open the Main menu.

5. Turn the dial until the option “Start Warm-up Cycle” appears.

6. Click again on the left dial. A confirmation message appears. Select “Yes”.

7. The warm up cycle is starting now. The holder will warm-up to 40 degrees and cool down again to room temperature. The holder can be used again by the next user.

 Bake out cycle (old holder)

A bake out is generally only performed by BECM staff. The procedure happens at least once a month. If the holder cannot keep the temperature and/or the dewar starts freezing, a bake out has to be performed.

1. Insert the holder in the Turbo pumping station and make sure that the valves V1 and V2 are open to allow pumping on the tip of the holder. Connect the plastic tube from V3 to the holder. Connect the cable of the heat controller to the holder. Important: Do not twist the cable while connecting.

2. Open Valve V3 and wait until the vacuum recovers. Then open the valve on the dewar.

3.  If the controller is off: Switch on the power of the heat controller on the backside. The front panel will indicate the current measured temperature of the holder.

4. Click on the dial on the outer left. This will open the Main menu.

5. Turn the dial until the option “Start Zeolite Cycle” appears.

6. Click again on the left outer left dial and a new menu appears.

7. A further click on the outer left dial will allow you to change the Duration of the Zeolite cycle by turning the dial (Indicated by the “*” before the hour). Set at least to 8h but not longer than until the next day for usage in the morning.

8. Confirm by pressing the yes button.

9. The holder will start warming up to 100 degrees. The bake out timer only starts once this temperature is reached. If the temperature cannot be reached, there is likely a problem with the turbo pumping station to create the vacuum.

10. Important: At the end of the bake out, wait until the holder is back to room temperature. Now you can close the valve on the dewar and valve 3 on the turbo pumping station. The plastic tube can be disconnected from the dewar of the cryo holder. The cryo holder is ready for usage again.

 New Cryo holder

The new holder, its transfer station and tool box are labeled with a red sticker. Only use the right set of tools with it.

Warm-up cycle (new holder)

1. Insert the holder in the Turbo pumping station and make sure that the valves V1 and V2 are open to allow pumping on the tip of the holder. Connect the cable of the heat controller to the holder.

2. Rotate the holder, so that the opening of the dewar faces to the ground.

3. If the controller is off: Switch on the main power of the heat controller in the back. Push the Gatan “G” symbol for startup of the controller. You will hear the fan starting up.

4. After a short period of time, click on the panel to reconnect to the holder.

5. The display will generally be in “Automatic”. Here, you just read out the current holder temperature. Click on “mode”.

6. In the menu select “Ramp” and go “back”.

7. If the parameter are “0 to 40 C” and “20:00 duration”, just click Start. Otherwise, click on the Ramp menu on the top right corner.

8. Set all parameter to the ones displayed above and click “back”.

9. Select “Start”. The holder will be warmed up to 40 degrees. Starting at 0 degrees the timer will run. After the time ran out, the holder will cool down back to room temperature and is ready to use again.

Bake out cycle (new holder)

A bake out is generally only performed by BECM staff. The procedure happens at least once a month. If the holder cannot keep the temperature and/or the dewar starts freezing, a bake out has to be performed.

1. Insert the holder in the Turbo pumping station and make sure that the valves V1 and V2 are open to allow pumping on the tip of the holder. Connect the plastic tube from V3 to the holder. Connect the cable of the heat controller to the holder.

2. Open Valve V3 and wait until the vacuum recovers. Then open the valve on the dewar.

3. If the controller is off: Switch on the main power of the heat controller in the back. Push the Gatan “G” symbol for startup of the controller. You will hear the fan starting up.

4. After a short period of time, click on the panel to reconnect to the holder.

5. The display will generally be in “Automatic”. Here, you just read out the current holder temperature. Click on “mode”.

6. In the menu select “Bake out” and go “back”.

7. If the parameter are minimum “8:00:00 duration”, just click Start. Make sure that it is finishing before the user on the next morning. Otherwise, click on the Bake out menu on the top right corner.

8. Make sure that the temperature is set to 100 degrees and set the duration to at least 8 hours but not longer than until the next user starts in the morning.

9. Select “Start”. The holder will be warmed up to 100 degrees. If the temperature cannot be reached, there is likely a problem with the turbo pumping station to create the vacuum.

10. Important: At the end of the bake out, wait until the holder is back to room temperature. Now you can close the valve on the dewar and valve 3 on the turbo pumping station. The plastic tube can be disconnected from the dewar of the cryo holder. The cryo holder is ready for usage again.