Bruker 300'89 Ascend, User Manual

Page: 53 / 100

53 ZTKS0168 / Z31960 / 05
Troubleshooting
6.2.7 During De-energizing and Warming
Indicator Possible reason Solution Performed by
The magnet
system quenches
during
de-energizing.
The helium level
was too low for
de-energizing.
Refill helium at least to the
minimum allowed level. Bruker Service
The Power Supply
is defective. Replace Power Supply. Bruker Service
The main current is
oscillating. Replace Power Supply. Bruker Service
The shim current
can not be set
correctly. The control cable is
not connected
correctly to the
current lead and/or
the Power Supply. Connect the control cable to
the current lead and to the
Power Supply correctly. Bruker Service
The switch "Main
Coil/OFF/Shim
Coil" is not on the
"Shim Coil"
position. Switch "Main Coil/OFF/Shim
Coil" on the "Shim Coil"
position. Bruker Service
High helium flow
after breaking
vacuum. Remaining
cryogenic agents in
the vessels. Remove liquid cryogenic
agents. Bruker Service
Vacuum still
remains after
12 hours. Vacuum valve is
closed. Open the vacuum valve.
Block it if necessary. Bruker Service
RT vessel is wet
and cold. Cryostat is still
cold. Wait until RT vessel is dry
and warm. Check PT100
temperature sensors. Bruker Service
RT bore is wet and
cold before
disassembling. Cryostat is still
cold. Wait one more day. Do not
open a cryostat before the
room temperature bore tube
is warm and dry! Bruker Service