Download Ferritometer® Biomagnetic Liver Susceptometer

10.2.2 Sensor Maintenance
Water and ice must be kept off the sensor in order to have reliable readings. If ice forms on the
electrical connectors at the top of the dewar, the readings may not be accurate.
10.3 Bed Maintenance
The bed must be lubricated every three months and the belts checked for tension. Care--Watch
for the pulley screw on the motor if power is applied and the motor turns. This is not
recommended. Do not apply power if the sides are uncovered.
10.4 Water Bag Maintenance
The water bag must be checked for leaks periodically and the system kept free of trapped air.
Maintenance of the water bag is covered in a separate document.
10.5 Mechanical Pump Maintenance
Check the pump for backstreaming and oil periodically.
10.6 Transfer Tube Maintenance
The two piece flexible transfer tube has an evacuated region in each section between the inner
tube and the outer tube which is at room temperature. If the vacuum deteriorates, then the
thermal isolation between the two tubes will also deteriorate, and the outer tube will frost up
along its whole length when a transfer is attempted. It is possible that it will be impossible to
transfer any liquid helium. The cause of such a deterioration may be either a leak or the mistaken
opening of the evacuation valve. If the problem is a leak, it must be fixed. After repair, the
transfer tube vacuum space must be evacuated before the transfer tube can be used. As little as
1/2 hour of pumping with a mechanical vacuum pump should be sufficient.
11 Appendices
11.1 Hardware PC and National cards setup
Channel list is shown below:
Channel assignment
NI 6031 (64 Ch)
100 pin
Callout
ribbon
AI SQUID A
3-4
A0,8
1
2 SQUID B
5-6
1,9
3 SQUID C
7-8
2,10
4 H20
9-10
3,11
Pressure
5 Z Position
11-12
4,12
6 Cardiac
13-14
5,13
7 X fluxgate
15-16
6,14
8 Y fluxgate
17-18
7,15
Model 5700 Biosusceptometer
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7/3/99