GMW 5203, User Manual

Page: 20 / 71

18
5. OPERATION
The 5203 electromagnet is water cooled and should not be operated without water.
Attempts to operate the magnet as an air cooled system will most likely result in
irreversible damage to the magnet.
This product is an electromagnet and creates significant magnetic fields both within
the magnet and in the surrounding area. Make sure that there are no ferromagnetic
items, tools or components loose in a 1 meter radius surrounding the magnet.
The Model 5203 is not a shielded electromagnet. In operation the magnet fringing
field can be in excess of 0.5mT (5G). This can cause malfunctioning of heart
pacemakers and other medical implants. We recommend that the fringing field should
be mapped and warning signs be placed outside the 0.5mT (5G) contour. Entry to this
region of higher field should be restricted to qualified personnel.
Do not move magnetically sensitive items into the close vicinity of the magnet. Even
some anti-magnetic watches can be damaged when placed in close proximity to the
magnet during operation. Credit cards, and magnetic disks are affected by magnetic
fields as low as 0.5mT (5G).
5.1 Initial Operation
The magnet system in its most basic configuration will consist of the electromagnet and a suitable
DC power supply. Options are available to improve usability by providing better feedback of the
magnet interlock status, computer control, and magnetic field monitoring and control.
1.
Adjust the cooling water flow to approximately 8 liters/min (2.1 US gpm). For operation at
less than maximum power the water flow may be correspondingly reduced. Note that the inlet
water temperature will determine the actual flow rate required. The above specified flow rates
were determined with a water inlet temperature of approximately 18°C.
2.
Set the DC power supply voltage and current controls to zero and switch on the power supply.
For maximum stability, the power supply should be operated in 'current mode', and most power
supplies will automatically switch modes depending on which control is set LOWER as the
lower control would be the limiting factor.
3.
Switch on the DC power supply. To operate in the current mode, the voltage control must be
set to a sufficiently high level to allow the desired current to be set: With the current control at
its minimum, turn the voltage control up, and then adjust the current control to the desired
output. Should the current control stop responding, it is likely that the system has switched to
voltage mode. In that case, adjust the voltage control higher and then continue adjusting the
current control.
At this point the magnetic field should be checked to verify that the field being generated
corresponds correctly with data given for the Excitation Curve. Refer to Section 7 - 'Excitation
Curves' for excitation graphs that most closely resembles your magnet configuration.