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--- stm:manual_setting_of_the_magnetic_field [2006/06/09 13:22] – galli
+++ stm:manual_setting_of_the_magnetic_field [2007/01/29 18:01] (current) – galli
@@ Line 1: / Line 1: @@
+====== Manual Setting of the Magnetic Field ======
+===== Driven Mode =====
+Advantage: faster field sweeps. Disadvantage: helium consupmtion and noise increased.
+  - Superconducting switch HEATER ON. Wait 1 minute.
+  - Select right MID set point with SELECT on keypad.
+  - Press MID toggle button.
+  - To change set point to a smaller or bigger value, just change MID set point and re-press MID if not already toggled on.
+  - Note that you can PAUSE the ramp at any moment with PAUSE.
+===== Persistent Mode =====
+Advantage: less noise and helium consumption, field more stable. Disadvantage: slower to change field.
+  - Superconducting switch HEATER ON. Wait 1 minute.
+  - Energize to desired current/field setpoint (by pre selecting the desired MID setpoint and pressing MID).
+  - Wait about 1 minute for current to stabilize.
+  - Turn OFF superconducting switch HEATER.
+  - Wait 1 minute for switch to become superconducting.
+  - Set current to ZERO, slowly first and at lower current the rate can be increased.
+  - Now you can possibly switch the magnet power supply off.
+To set the field back to ZERO or to a different value:
+  - Switch HEATER still OFF.
+  - Ramp up the current to previous value and wait till value is reached.
+  - Switch's HEATER ON. Wait 1 minute.
+  - Change set point by changing MID. Press MID (or ZER0).
+  - Wait about 1 minute for current to stabilize.
+  - Turn OFF superconducting switch HEATER.
+  - Wait 1 minute for switch to become superconducting.
+  - Repeat, as written above, the procedure to ramp the current to ZERO and switch off the power supply.