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Slow and Fast Magnets Functional! Lab Book 2014_08_27

Summary:  Most of the morning was spent hooking up the last few wires on the iron magnet, and figuring out which section of EM I’ll be TA’ing for.  In the afternoon, the pulsed current supply for the fast magnet was fired while taking background spectral data with the NaI detector.  There was no recognizable effect caused by firing the pulser.

If you're new to the experiment, please scroll to the bottom for background information.

Magnet Work
Spades were attached to the four wires of the three phase power cord.  These were in turn attached to the magnet power supply. 




The power supply case was grounded per the instructions



The chiller was turned on along with the coil cooling supply, (the sink faucet).  The flow of the coil cooling supply was increased until the bucket/timer flow meter indicated two gallons per minute.  The position of the cold water know with a flow of two gallons per minute is shown below.


When the chiller is operating, the flow meter for the power supply should appear as follows.


The supply did not energize on the first attempt.  The breaker was off.  When the breaker was turned back on, the power supply operated correctly.



Chiller alarms:  The chiller occasionally sounds an alarm.  The typical fix is to increase the water level in the chiller.  This procedure worked today.

Operational tests:
The magnet has been operated at currents up to five Amperes for less than a minute.




Detector Work
Bias
1500 V
Gate Window
0.5 uS
Threshold
1.5mV
Attenuation
0 dB
Data set
HBC_00023
Source
3? Pulsed magnet shots
Start Time
2:55 PM
Stop Time
3:00 PM, (5:01 minutes:seconds)
verified on video
Date
2014_08_20 – 2014_08_21
x-y scope V/div
1, 0.5
Shielded?
Yes
Tube
Harshaw B-

Background check
Bias
1500 V
Gate Window
0.5 uS
Threshold
1.5mV
Attenuation
0 dB
Data set
HBC_00024
Source
Background
Start Time
2:55 PM
Stop Time
3:00 PM, (5:33 minutes:seconds)
Date
2014_08_20 – 2014_08_21
x-y scope V/div
1, 0.5
Shielded?
Yes
Tube
Harshaw B-

The graph below shows no significant difference between the spectral data gathered while the pulsed magnetic field was fired four times, and that gathered with no pulsing of the magnet current supply.


Simulator Work
The simulator is back up and running.  The following output is for a coil 1.6 cm in diameter that would hold the small YBCO sample.  The labels on the magnetic field plot are not correct.  An issue has been filed on the simulator code.






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