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List of Tables
Table Title Page
1-1. Hydra Features......................................................................................................... 1-6
1-2. Accessories ............................................................................................................ 1-7
1-3. 2620A/2625A Specifications................................................................................. 1-8
1-4. 2635A Specifications............................................................................................. 1-20
2-1. Microprocessor Memory Map............................................................................... 2-11
2-2. Option Type Sensing ............................................................................................. 2-14
2-3. Programmable Input Threshold Levels ................................................................. 2-15
2-4. Analog Measurement Processor Pin Descriptions ................................................ 2-19
2-5. Function Relay States ............................................................................................ 2-21
2-6. AC Volts Input Signal Dividers............................................................................. 2-25
2-7. Front Panel Switch Scanning................................................................................. 2-29
2-8. Display Initialization Modes ................................................................................. 2-32
2A-1. Microprocessor Interrupt Sources (2635A)........................................................... 2A-12
2A-2. Booting Microprocessor Memory Map (2635A)................................................... 2A-13
2A-3. Instrument Microprocessor Memory Map (2635A).............................................. 2A-13
2A-4. Analog Measurement Processor Pin Descriptions (2635A).................................. 2A-22
2A-5. Function Relay States (2635A).............................................................................. 2A-24
2A-6. AC Volts Input Signal Dividers (2635A).............................................................. 2A-28
2A-7. Front Panel Switch Scanning (2635A) .................................................................. 2A-33
2A-8. Display Initialization Modes (2635A)................................................................... 2A-36
4-1. Recommended Test Equipment............................................................................. 4-3
4-2. Performance Tests (Voltage, Resistane, and Frequency)...................................... 4-5
4-3. Thermocouplt Information .................................................................................... 4-10
4-4. Performance Tests for Thermocouple Temperature Function............................... 4-10
4-5. Performance Tests for RTD Temperature Function (Resistance Source)............. 4-12
4-6. Performance Tests for RTD Temperature Function (DIN/IEC 751)..................... 4-13
4-7. Digital Input Values............................................................................................... 4-14
4-8. Calibration Mode Computer Interface Commands ............................................... 4-20
4-9. DC Volts Calibration............................................................................................. 4-23
4-10. AC Volts Calibration............................................................................................. 4-24
4-11. 4-Wire Ohms Calibration (Fixed Resistor) ........................................................... 4-27
4-12. 4-Wire Ohms Calibration (5700A)........................................................................ 4-28
4-13. Frequency Calibration ........................................................................................... 4-29
5-1. Error Codes............................................................................................................ 5-5
5-2. Preregulated Power Supplies................................................................................. 5-6