
E3730A OPERATING INSTRUCTIONS
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Check the ion pump current. The klystron has been conditioned for weeks in ultra-high vacuum.
Out-gassing from the tube body is very little. The ion pump current is far less than ten
micro-amperes. When ion pump does not start because of very low residual gas pressure, ion
pump can be started when the filament is lit on. Do not give mechanical or electrical shock or
vibration to the ion pump in order to start it.
After long period of storage without pumping, residual gas may give a large ion pump
current more than tens of micro-amperes. Usually the ion pump easily evacuates this residual gas
in several minutes.
6.1.3.11. Connect the cooling water pipings
Connect the cooling water pipings to the water inlet and the outlet of the klystron. The
connectors of the klystron mate with "SP-coupler" size 4S for the inlet and 4P for the outlet of
NiTTO KOHKI COUPLER from NITTO KOHKI Shanghai Office [#1117 Ruijin Building, 205
Maoming South Road, Shanghai, China, TEL(21)6415-3935&(21)-6415-3922, FAX(21)6472-6957].
6.1.3.12. Electrical connection of the electromagnet
Be sure all the power supplies connected to the electromagnet and the associated circuitry
are not energized and properly grounded. Make the electromagnet electrical connection. Connect
a pair of wire to the terminal board on the side wall of the electromagnet. Make the connections of
the thermal interlock output.
6.1.3.13. Electromagnet water piping
Connect the cooling water piping. The connectors mate with "SP-coupler" size 4S for the
inlet and 4P for the outlet of NITTO KOHKI COUPLER from NITTO KOHKI U.S.A. INC.
6.1.4. Checks
6.1.4.1. Ion-pump power supply
Check the overcurrent relay is set for the value of 2 microamperes. This relay cuts off the
klystron high voltage when actuated. Apply the rated voltage of 3.5 plus minus 0.4kV to the pump.
Wait for several minutes until the current decreases to less than 1 microamperes, after a current
peak that may reach several tens of microamperes. In case that the voltage is much less than the
nominal value and the current still takes tens of microamperes 10 minutes later, the tube is very
suspicious of poor vacuum. Please call immediately Electron Tube Division.
6.1.4.2. Output waveguide vacuum
The E3730A klystron is designed with waveguides evacuated to less than 1.3x10
-5
Pa (10
-7
torr). Check the evacuating system is in normal operation and the vacuum gauge is correctly
operating. Be sure that the vacuum pressure is less than the value described above. Check the
interlock relay of the vacuum gauge is set for the value described above, and the interlock system
does properly cut off the klystron HV.
6.1.4.3. Water flow