Micromeritics SediGraph III 5120 Service Manual page 29

SediGraph III 5120 Service
Access to the high voltage supply is gained by removing the top panel, then removing the
internal side mounting panel.
Quad switching power supply (PN 003/40002/00) supplies 5VDC, + 15VDC and 24VDC. The
5VDC is used for the front panel Power Led, logic and enables while the + 15VDC is used for
the CMOS logic, the 24VDC output goes to the three fans in the instrument.
Access to the quad switcher is gained by removing the top panel then locating the supply in the
rear of the instrument.
There is also a high voltage supply for the PMT supply (PN 003/40023/02) located on the X-
ray control PCB. This supply powers the Photo Multiplier Tube and is internally controlled. Its
output range is 700VDC to 1300 VDC, typically the final setting is around 1000Volts.
Access to the PMT high voltage supply is gained by removing the top panel, then removing
the internal side mounting panel opposite the X-ray tube.
The 24VDC power supply (PN 003/40049/00) with universal input, is capable of 350 watts
and supplies power to the X-ray tubes HI voltage power supply, PMT HI voltage supply, pump
motors, valve assemblies, cell drive motor, key-switch lamps, instrument fans, RTDs and
heaters, the fan in the Analysis module used for the heaters, and the stirrer motor.
Access to the 24VDC power supply is gained by removing the top panel, then locating the
supply in the right side in the rear of the instrument.
Mar 2010
Power Supplies and Power Entrance
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