GMW 5203, User Manual

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4.6 Magnet Power Connections
Never connect or remove cables from the magnet with the power supply energized.
The stored energy in the magnet can cause arcing resulting in severe injury or
equipment damage.
Follow the lockout/tagout procedure as described in Section 1, Lockout/Tagout prior
to connecting or removing the DC power cables.
The magnet is shipped with a power and interlock cable attached. The recommended current cable
for the 5203 is shown in Drawing 16907-0116-1-S1_A (section 12). Because the magnet stores a
significant amount of energy in its magnetic field, special care should be taken to ensure that the
current terminations are secure and cannot work loose in operation. Local heating at the
terminations can cause rapid oxidation leading to a high contact resistance and high power
dissipation at the terminals. If left unattended this can cause enough local heating to damage the
terminals and the coils.
4.7 5203 Interlocks
In the event of an interlock tripping it is strongly recommended that the root cause of
the trip be determined. In the event that the root cause cannot be determined please
contact Tom King (tom@gmw.com) for technical support.
The Model 5203 has one Selco UP62-080C thermostat. It is located between the base yoke plate and
the lower cooling plate. The thermostat is normally closed, opening when the coil heatsink
temperature exceeds 80°C, ± 5°C.
The interlock circuit also includes a flow switch (GEMS FS-380) located at the junction box. This
flow switch is open for flow rates above 5.4 lpm (1.5 US gpm).
4.8 Interlock Testing
It is crucial that before general operation of the magnet system, that the interlock
circuits be tested. This test requires that the terminal cover be removed from the
magnet while energized and therefore must be completed by a qualified electrician.
This test should be done with the magnet operating with a LOW power setting,
preferably less than 5 amps.
DO NOT AT ANY POINT TOUCH OR DISCONNECT THE MAGNET
POWER CABLES.
Thermal Switches : Carefully remove one of the temperature switch connections from the interlock
termination block. The power supply output MUST enter a disabled state. Reconnect the
connection and the power supply output should return to normal.
Flow Switch : Shut off the water supply to the magnet. The power supply output MUST enter a
disabled state. Restore the water supply and the power supply output should return to normal.
This interlock testing procedure should be carried out no less than every six months.