MAGNET

THE 9T MAGNET

... is working but this page is under construction :)

First test with 50Amps (~5.7T) worked!

In the picture a threaded rod is attracted by the magnet at 50A.

Operate the Magnet

• Power Supply : OXFORD IPS 120-10 (Max.12 Amp @10Volt)
  • Software Remote-control: IPS_120-10_v03.vi
  • ! Change of Range when increasing the current at ~4.3A, when decreasing at ~3.4A! Don't get scared by the noise :)
• Upper Magnet, Connection on window side of cryo. Power-cable are marked red (+) and blue (-).
• Persistent current switch:
  • Upper magnet - BOX VII, X9:1/4 ,R_Heater(4K)=135${\Omega }$.
  • I_Heater=55mA. The TVL-10 is used as current supply.

Magnetisation and Demagnetisation Procedure

• After ramping the magnet the magnetized first nuclear stage must be precooled. The temperature dependence varies as T~t^-1/3.
• The first nuclear stage was demagnetized by reducing the field in steps by a factor of 2 to a final field of few mT.
• Sweep Rate B>0.5T : R=2T/h.
• Sweep Rate B<0.5T : decrease by a factor of 2 proportional to the field.

Upper Magnet UMM

• I/B-Conversion: 10A=1T (? not yet clarified, date: 14.Dec 2011)
• Sweep Rate: 1 T/h = 10 A/h = 0.167 A/min

Lower Magnet LMM

• I/B-Conversion: 0.8T=6.96A -> B (I[A]) = 0.115 T/A *I[A]

Connection

• To Power supply: M6 (13Rigschlüssle, 6erInbus).
• To Upper Magnet: Connection on window side.
• To lower magnet: Connection on door side of the cryostat.