American Magnetics 110 Liquid Helium Level Meter (CE-Marked) - Manual (Page 24)

14
Service Guide
Custom Instrument Configurations
4. Ensure the sensor is not installed in a restricted area which
prohibits the level of helium around the area of the sensor to be an
accurate representation of the level to be measured. The gas
produced by the sensor when the sensor current is on can depress
the liquid level.
5. Ensure the sensor is installed with lead wires at the top. Due to the
physical construction of the AMI LHe sensor, a reading of 100% will
always result if the sensor is installed upside down.
4.2 Custom Instrument Configurations
4.2.1 Modifying the line voltage requirements
Warning
Before removing the cover of the instrument, remove the power from
the instrument by disconnecting the power cord from the power
receptacle. Failure to do this could expose the user to high voltages
and could result in life-threatening electrical shock.
Caution
The Model 110A instrument operates on 50-60 Hz power and may be
configured for 100-120 VAC or 200-240 VAC
±
10%. The power
requirements for each instrument are marked on the rear panel. Be
sure the instrument’s power requirements match your power source
prior to plugging in the line cord. Do not fail to connect the input
ground terminal securely to an external earth ground.
If the instrument operating voltage needs to be changed, ensure the
instrument is de-energized by disconnecting the power cord from the
power source. Remove the instrument cover and slide the voltage selector
switch on the main printed circuit board to the proper voltage. Replace the
instrument cover and indelibly mark the rear panel indications to match
the new configuration.
4.3 Additional Technical Support
If the cause of a problem cannot be located, contact an AMI Technical
Support Representative at (865) 482-1056 for assistance. The AMI
technical support group may also be reached by Internet e-mail at
VXSSRUW#DPHULFDQPDJQHWLFVFRP . Additional technical information,
latest software releases, etc. are available at the AMI World Wide Web site
at: