8
Electronics
AC board
241
AC board
The ac board is mounted on the opposite side of the electronics panel from the
HP-IB/MS control card. The ac board is also sometimes called the power distribu-
tion / vacuum control board. The ac board performs the following functions:
•
Has two sockets for connecting the toroid transformer. The socket used
depends on the line voltage.
•
Distributes ac line power to the ac/dc power supply, the foreline pump, the
toroid transformer.
•
Turns on the diffusion pump once the foreline pressure is low enough.
•
Regulates the ac power to the diffusion pump heater.
•
Turns off the diffusion pump if the foreline pressure is too high or if the diffusion
pump is too hot.
•
Controls the foreline gauge.
•
Passes the foreline pressure signal from the foreline gauge or turbo pump speed
and other vacuum status information to the main board.
•
Turns off the foreline pump in case of a problem with pumpdown.
•
Provides power and logic interface to turbo controller.
•
Turns the calibration valve on or off as directed to by the main board.
•
Turns the diffusion pump on or off as directed to by the main board.
•
Provides the voltage for the calibration valve.
The power regulator ensures that the diffusion pump heater receives constant
power, even if there are fluctuations in the ac line voltage. It measures the voltage
across the heater and the current through it, multiplies them together, and com-
pares the result with a standard value. Any discrepancy is applied as an error sig-
nal to adjust the power.
If the power distribution board senses a malfunction in the diffusion pump power
regulator, it shuts off power to the diffusion pump.
In turbo pump MSDs, the ac board sends control signals to, and receives turbo
pump status information from, the turbo pump controller.
Summary of Contents for 5973
Page 1: ...H Hardware Manual HP 5973 Mass Selective Detector ...
Page 3: ...HP 5973 Mass Selective Detector Hardware Manual ...
Page 25: ...1 Installing GC Columns To condition a capillary column 25 ...
Page 30: ...30 ...
Page 37: ...2 Operating the MSD To view MSD analyzer temperature and vacuum status 37 ...
Page 39: ...2 Operating the MSD To set monitors for MSD temperature and vacuum status 39 ...
Page 41: ...2 Operating the MSD To set the MSD analyzer temperatures 41 ...
Page 43: ...2 Operating the MSD To set the interface temperature from the ChemStation 43 ...
Page 51: ...2 Operating the MSD To remove the MSD covers 51 Upper cover Lower cover ...
Page 92: ...92 ...
Page 105: ...4 Maintaining the MSD To drain the foreline pump 105 Fill cap Drain plug Pump motor ...
Page 113: ...4 Maintaining the MSD To separate the MSD from the GC 113 ...
Page 121: ...4 Maintaining the MSD To reconnect the MSD to the GC 121 ...
Page 141: ...4 Maintaining the MSD To lubricate the side plate O ring 141 Side plate O ring ...
Page 159: ...4 Maintaining the MSD To remove a filament 159 Filament 2 Filament 1 ...
Page 161: ...4 Maintaining the MSD To reinstall a filament 161 Filament 2 Filament 1 ...
Page 210: ...210 ...
Page 214: ...214 ...
Page 232: ...232 7 Analyzer Analyzer heaters and radiators ...
Page 280: ...280 ...
Page 294: ...294 Index ...
Page 296: ...294 Chapter ...
Page 297: ...H Manual Part Number G1099 90027 Copyright 1998 Hewlett Packard Printed in USA 11 98 ...