GMW 5203, Руководство пользователя

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4.9 Magnet Cooling
The Model 5203 can be operated up to an average coil temperature of 80°C. Assuming an ambient
laboratory temperature of 20°C and a temperature coefficient of resistivity for copper of 0.0039/°C,
the hot resistance of the coil should not exceed 25% more than the ambient temperature "cold"
resistance. The coil thermostat will open when any coil cooling plate temperature exceeds
approximately 80°C . Clean, cool (16°C 20°C) water at 8 l/min and 4 bar (60 psid) must be used to
cool the 5203 magnet.
The copper cooling tubes are electrically isolated from the coils to avoid electrochemical corrosion.
A 50 micron filter should be placed before the input to the magnet to trap particulates.
Configuration Suggestion: For continuous operation of the magnet it may be appropriate to use a
recirculating chiller to reduce water and drainage costs. The chiller capacity will depend on whether
cooling is required for the magnet alone or magnet and power supply.
Do not use corrosion inhibitors in high quality electrical systems since the water conductivity is
increased which can result in increased leakage currents and electrochemical corrosion.
Avoid cooling the magnet below the dew point of the ambient air. Condensation may cause
electrical shorts and corrosion.
During operation the resistance can be checked using a voltmeter across each coil. The voltage will
rise to a constant value once thermal equilibrium has been reached. If it is desired to save water, the
water flow may be reduced until the hot resistance is approached. NOTE: This adjustment must be
made slowly enough to allow for the thermal inertia of the coils.