First check to see if you can fix the problem. Following are some frequently encounted problems and how to deal with them. If you can not fix or are not sure about it, you should call the cryotarget on-call person (listed on the whiteboard in the counting house).

Cryotarget lifting are selected from the `position' menu item on the `atarg' GUI. To move the target, first call MCC to have the beam turned off and mask FSD, as well as to tell them what new target you are going to. Once the beam is off and the FSD is masked, click the appropriate button corresponding to the target you want in the Lifter GUI, the target will start to move. While it is moving, the `busy' and the `status' lights on the Lifter GUI should light up. The encoder position in the Lifter GUI and the GUI cartoon will also change. It may take a few minutes for the target to move to the new position. You're there when the busy and status lights go out and the break light on, and the green light goes on at the new position, and the encoder position has reached the right value. When you're finished you call MCC again, have them reset the FSD mask and give us back the beam.

First you should clear the software record by clicking on CLEAR SLECETED RECORD. Try to move again. If still not working, you can try to reboot IOC (see how to reboot the cryotarget IOC). This solves the problem most of the time. If the problem is still there, next you can try to restart the cryotarget GUIs (exit all the GUIs, then follow How to start the GUIs from scratch). If the problem persist, you need to call the cryotarget on-call person (listed on the whiteboard).

To service an alarm, first click the button on the Alarm GUI. This launches an alarm tree GUI which lights up those elements in the tree which have gone outside their limits. Go to the lowest, rightmost button which is lit up and click on its name. { Always service alarms from the lowest branch in the tree!} This will bring up another GUI which shows the current value, the high and low alarm limits, and the more extreme hihi and lolo alarm limits for each item in the category you just clicked on. The offending items are highlighted. Jot down which item is causing the alarm. If by this time it is still out of the alarm limits you have a problem. Call one of the target contact people to find out what to do. They may advise you to change the alarm limits, but this should only be done or sanctioned by one of the target experts/contacts (Chen, LeRose, Meekins, Keith). The more usual case is that the value has returned to its nominal value (such as the alarm due to condition change caused by beam off/on). In that case, all you have to do is click on the lit button in the leftmost column and that'll take care of it. Continue doing this until all alarms have been serviced.

You need to reboot the target IOC if the strip charts have flatlined, and/or the heartbeat GUI has stopped beating, or some of the normal functions stopped working (for example, you can not move the target). Don't panic, the target remains in PID mode even when the IOC has died. But you're running blind until you reboot. During the reboot, the PID mode goes off. For the deuterium target, to prevent any potencial of freezing (freezing temperature is 18.7 K), a constant auxillary power supply should be used before robooting the IOC. For the helium and the hydrogen targets, you can proceed directly to rebooting the IOC. The first thing to do is inform the shift leader that you need to reboot cryotarget IOC so the shift leader (or you) can stop run. For deuterium target only: Before you reboot, you have to supply a constant auxillary power to the heaters. You need to know approximately what the heater power is for the deuterium loop when the beam is off. It is a good idea to write this down when you started your shift. The auxillary high power heater power supply and the switch box are right above the Reset IOC button. Turn on the deuteirum loop (usually loop 2) power supply. Turn on the switch box power. Dial in the appropriate setting for the power supply. You can proceed to reboot the IOC. To reboot ioc, open a web page, go to hareboot7. Log on as hlauser (password on the wall in the counting house). Click on the iocha13. Then click on CONTROL. Check both 5 and 6. In the pulldown manu, choose Reboot Immediately. Click on Next. Then click on Apply. The ioc reboot will take a few minutes. During that time, when the ioc first comes back, you will hear some alarms. Wait for a few minutes, all should go back to normal. After that, check the high power heater to make sure it is in PID mode. If it is not in PID mode after waiting for a few minutes, click `PID' to put it in PID mode. (For Deuterium target only: now it's the time to switch the auxillary heater power supply back to the regular power supply). Check the fan and click `update' button. Check the charts to make sure everything back to normal. Service the alarms when things are settled down. When you are all done, inform the shift leader that the cryotarget is ready. Don't forget to log the target IOC reboot in halog.

To start the target control software, logon on to the target PC poltarac under the poltar account, you need to get the password during the training (also on the wall in the counting house). Type `cd Screens' to get to the correct directory, then launch the software by typing `./tgtgui'. Don't put this in the background, messages need to go to this window. The main target GUI will appear.

Now on the main target GUI, click on the `alarm' button. Click `OK' in the dialogue box, ctarg.alh will get loaded and your alarm GUI will appear.

Launch the working loop GUI by clicking on that loop (loop 3 for LH2 for HAPPEX3). Click on `Chart' to get the displays.

Since the high power heater power is linked to the temperature in each loop via a feedback (PID) mechanism, you can't affect the heater power directly. To adjust the heater power, you adjust the JT valves. Click on the JT valve button on the loop GUI. Set the step size to be a small value (say, 0.5%). Click on the J-T loop open (or close) button to change the J-T valve value. You should do it slowly, say, no more than one percent every 30 seconds). Watch the high power heat value change in the loop chart. Note that the high pwer heaters have upper limits associated with them (set in the high power heater GUI). These upper limits may prevent you from going as high as you want with the heater power, if so change the limit. If you are not sure, contact the cryotarget on-call.

The fan speed (accessible from the FAN in the LOOP GUI) can be adjusted. The nominal setting is 25% (of full speed) which is 60~Hz (the tachometer should read back 60 Hz for normal running). In the regime we're operating in, a higher fan speed actually raises the temperature a little due to the increased heat load put out by the fan motor. The fan frequency may be lowered on loops which will not be in the beam for long time (to 10% or 24 Hz). If you put them back into the beam you should raise the fan frequency back up to 60 Hz to mitigate local boiling.

The target operator should usually not need to open the Warm return valve. Only in special situation when the cryotarget warmed up, the return coolant is too warm (temperature higher than 30 K), the cryo-group may want to close the cold return valve (which is controlled by the cryo-group). Then they will need us to open the Warm Return Valve (which is controlled by us). In this situation, the cryotarget on-call should be called in. However, at the mean time you should comply with the request from cryo-group to open the Warm Return Valve. To open the Warm Return Valve, click 'device' on the atarg control GUI, choose the Warm Return, which will open a new `Warm Return Valve' panel. The value shown is the percentage open (0-100%). It should be a value near 0 (closed). Every time click only ONCE on the `energize' button next to `7 Warm Return Close'. Wait for the status button go from red 0 to green 1 for a second and change back to red 0. Watch the valve value. Now you can click again. The usual procedure is that the cryo-group (or MCC) will close the Cold Return to 75%, then ask us to open the Warm Return by 50%, and they will close the Cold Return to 25% and ask us to fully open (100%) the Warm Return and then they will fully close the Cold Return.
(Special Note: due to calibration problem, the readback value of the valve openning is 0-40 instead of 0-100. 40 is fully open).

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