Power Supplies And Power Entrance - Micromeritics SediGraph III 5120 Service Manual

Power Supplies and Power Entrance

Power Supplies and Power Entrance
There are four power supplies used in the SediGraph:
• X-ray High Voltage
• Photo Multiplier Tube high voltage
• 24VDC
• Quad Switching power supply
Two of these supplies are located in the back of the instrument, behind the rear panel. The
24VDC supply is on the right hand side of the instrument, while the quad switcher is on the
panel facing you when the rear panel is removed. The X-ray high voltage is located under the
X-ray shield, which is mounted on a heat sink on the inner cabinetry. The Photo Multiplier
Tubes supply is located on the X-ray control PCB.
Exercise extreme caution when measuring or setting the high voltage. Follow all
safety precautions as voltage in excess of 13,000 volts DC is present.
The high voltage (PN 003/40062/00) supply is used to operate the X-ray tube. This power
supply is located under the top panel on the left side (looking from the front) under the X-ray
shield. It provides the accelerating voltage for the X-ray tube and has sense lines feeding back
to the X-ray control board, which are used to control the supply. The maximum output voltage
is 15,000VDC. The voltage is set for an output of 13,600VDC.
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SediGraph III 5120 Service
Mar 2010