Specifications

RUSKA 7250, 7250i, 7250xi & 7250LP
Users Manual
ii
Standard Equipment and Options ...................................................................... 1-5
2 Theory of Operation ............................................................................ 2-1
Introduction........................................................................................................ 2-1
Power Supply..................................................................................................... 2-1
Electronics Module ............................................................................................ 2-2
Back-Plane Board.......................................................................................... 2-2
Microprocessor Board ................................................................................... 2-2
Digital Control Board .................................................................................... 2-3
IEEE–488 Interface ....................................................................................... 2-3
Front Panel..................................................................................................... 2-3
Pneumatics Module............................................................................................ 2-4
Measure Mode Pneumatics............................................................................ 2-6
Reference Port........................................................................................... 2-6
Test Port .................................................................................................... 2-6
Vent Procedure.......................................................................................... 2-7
Control Mode Pneumatics ............................................................................. 2-7
Pressure Supply Port ................................................................................. 2-7
Vacuum Supply (Exhaust) Port................................................................. 2-7
Pressure Control ........................................................................................ 2-7
Control Strategy................................................................................................. 2-7
Inner vs. Outer Loops .................................................................................... 2-7
Normal Mode................................................................................................. 2-8
Fast Mode ...................................................................................................... 2-8
Alignment of Inner Loop with Outer Loop ................................................... 2-8
PID Control ................................................................................................... 2-8
Transducer Module ............................................................................................ 2-9
Quartz Bourdon Tube Sensor (Transducer01)............................................... 2-9
Sensor Board ................................................................................................. 2-10
Linearization Term ........................................................................................ 2-10
Auxiliary Sensors .......................................................................................... 2-11
Case Reference Vacuum Sensor.................................................................... 2-11
Software............................................................................................................. 2-11
Software Safety Controls............................................................................... 2-11
Preventing Operator Errors ....................................................................... 2-11
Pneumatic Errors....................................................................................... 2-11
Shut Offs ................................................................................................... 2-11
Oven Control............................................................................................. 2-11
Pressure Reading and Correction .................................................................. 2-12
Zero Coefficients....................................................................................... 2-12
Range Coefficients .................................................................................... 2-13
3 Installation ........................................................................................... 3-1
Introduction........................................................................................................ 3-1
Unpacking the Calibrator................................................................................... 3-1
Cautions ............................................................................................................. 3-2
Powering Up the Calibrator ............................................................................... 3-2
Observing the Calibrator’s Full Scale Rating .................................................... 3-3
Pneumatic Connections...................................................................................... 3-3
Pressure Supply Port...................................................................................... 3-3
Exhaust Port................................................................................................... 3-3
Absolute Models............................................................................................ 3-3
Test Port ........................................................................................................ 3-3
Reference Port ............................................................................................... 3-4