49 
ZTKS0243 / Z31993 / 03
Troubleshooting
Continued from page before
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Indicator Possible reason Solution By
Shorting plug can 
not be removed.
The connector is 
covered with ice 
(frozen moisture or 
nitrogen ice).
Carefully remove the ice with 
warm helium gas. Use the 
dipstick or the precooling tube 
as tubing for the warm helium 
gas to remove small ice spots 
from the connector.
Bruker Service
The magnet system 
quenches.
Loss of 
superconductivity.
See chapter ”After a 
Quench” on page 55.
Bruker Service
The helium level was 
too low for energiz-
ing, cycling, 
shimming,  
de-energizing or 
sweeping.
See chapter ”After a 
Quench” on page 55.
Bruker Service
The Power Supply is 
defective. The main 
current is oscillating.
Replace the Power Supply. Bruker Service
The main coil switch 
can not be closed on 
field.
The helium level is 
too low for energiz-
ing. The main coil 
switch is not covered 
with liquid helium.
Never try to energize the 
magnet with less than the 
"minimum level during ener-
gizing" in the helium vessel.
Bruker Service
The Power Supply is 
defective. The main 
current is oscillating.
Replace the Power Supply. Bruker Service
Shim current can not 
be set correctly.
The control cable is 
not connected 
correctly to the 
current lead or to the 
Power Supply.
Connect the control cable 
correctly to current lead and 
power supply.
Bruker Service
Switch „Main Coil/
OFF/Shim Coil“ in 
wrong position.
Change the switch position. Bruker Service
Shims do not affect 
the NMR signal.
Shim heater current 
is not correct. The 
shim switches are 
not opened.
Set the shim heater current to 
the specified value (see 
Appendix Technical Data).
Bruker Service