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1. Before connecting the PSxxx-yy to the electricity supply, check the rating plate on the rear of the unit corresponds with the supply voltage being used. Now connect the magnet current leads and the persistent mode switch heater lead to the terminals inside the rear cover of the power supply.
2. Connect the leads to the cryostat magnet terminals and the appropriate ten pin seal. Check for electrical isolation from the cryostat.
3. Switch on the magnet power supply. The power supply will indicate successful initialization by displaying the firmware version e.g. 'PS2.04' then 0.00.
4. Select the mode of display required, this can be in Amps or Tesla by pressing the button labelled CURRENT/FIELD (the ratio of these is set in the software for a given magnet). Set the current or magnetic field to which magnet is to be energized by pressing the RAISE and LOWER buttons on the ADJUST panel while depressing the SET POINT button on the DISPLAY panel. Set the rate of change in a similar way by pressing RAISE and LOWER while depressing the SET RATE button. Please consult the results section of this manual for advised energization limits.
5. If the magnet is equipped with a persistent mode switch, press the HEATER ON button on the SWITCH HEATER panel. The button should be pressed, the indicator light will come on. Wait 30 seconds to allow the switch to heat up before proceeding.
6. The magnet energization can now be started by pressing the SET POINT button on the SWEEP CONTROL panel. The current or field will be seen to increase on the digital display and the output voltage will have been seen to kick to the voltage needed to overcome the magnet impedance on the analogue meter (if fitted, i.e. not the PS120-3).
7. When the set point has been reached, the switch heater can be turned off by pressing the HEATER ON button again. After waiting about 30 seconds for the switch to become superconducting, press the ZERO button on the SWEEP CONTROL panel. The current in the magnet leads will decrease to zero leaving the magnet, still energized, in persistent mode. The rate at which the leads alone can be swept is faster than the magnet and leads, this is automatically taken into account in the power supply firmware.
8. The magnet can be taken out of persistent mode by using the following procedure:
   Pressing the SET POINT button on the SWEEP CONTROL panel (the switch heater is left 'off'). The current leads will be swept at a fast rate to the Set Point value. Turn the switch heater current 'on' by pressing the HEATER ON button. Wait 30 seconds for the switch to warm up. Press the ZERO button on the SWEEP CONTROL panel and the magnet will start to de-energize. The Set Rate can be increased during the sweep without stopping.
   

   If it is desired to change the value of magnetic field, sweep the current leads to the present current or field of the magnet, press HOLD, open the switch by turning on the heater.  Press the SET POINT button and RAISE and LOWER to change the Set Point to the new desired value. Make changes to the Set Rate of sweep in a similar manner.  Press the SET POINT button on the SWEEP CONTROL panel and the magnet will either energize or de-energize to the new field

   If the voltage needed to drive the magnet at a given rate is such that the maximum voltage of the power supply will be exceeded, the power supply will trip into the ’Hold’ mode, and the HOLD light will illuminate, on the SWEEP CONTROL panel.  The sweep can continue, after a slower rate has been selected, and the SET POINT button has been depressed.
   In the event of a magnet quench, the power supply will trip to zero amps and the QUENCH light will illuminate. Useful facilities on the PSxxx-yy power supplies include automatic running down of the magnet (whatever state it is in) if the helium level falls below a threshold value.