Fluke 2680A Service Manual page 9

Open Thermocouple Detect Circuitry....................................................... 2-28
A4 Analog Input PCA Circuit Description ................................................... 2-28
A31 A/D Power Supply Circuit Description................................................. 2-29
Controller/System Power (Outguard) to A3 A/D Converter (Inguard)
Communications ........................................................................................... 2-29
Special Codes ................................................................................................ 2-29
Resets ............................................................................................................ 2-29
Commands..................................................................................................... 2-30
Perform Scan............................................................................................. 2-30
Perform Self-Test...................................................................................... 2-31
Return Firmware Version ......................................................................... 2-31
Return Boot Firmware Version................................................................. 2-31
Set Global Configuration .......................................................................... 2-32
Set Channel Configuration........................................................................ 2-32
Do Housekeeping...................................................................................... 2-32
Checksums .................................................................................................... 2-33
Errors............................................................................................................. 2-33
Power-Up Protocol........................................................................................ 2-33
Inguard Unresponsive ................................................................................... 2-33
Inguard Software Description ....................................................................... 2-33
Hardware Elements ....................................................................................... 2-34
Channel MUX........................................................................................... 2-34
Function Relays ........................................................................................ 2-35
Stallion Chip and Signal Conditioning ..................................................... 2-36
A/D ........................................................................................................... 2-39
DISCHARGE Signal ................................................................................ 2-42
Open-Thermocouple Detector .................................................................. 2-42
Channel Measurements ................................................................................. 2-42
Reading Rates ........................................................................................... 2-42
Measurement Types.................................................................................. 2-43
Autoranging .............................................................................................. 2-45
Overload ................................................................................................... 2-45
Housekeeping Readings ................................................................................ 2-45
Reading Types .......................................................................................... 2-45
Housekeeping Schedule............................................................................ 2-46
Self-Tests....................................................................................................... 2-47
Power-Up Self-Tests................................................................................. 2-47
Self-Test Command .................................................................................. 2-47
3 Maintenance ....................................................................................... 3-1
Introduction ....................................................................................................... 3-3
Self-Test Diagnostics and Error Codes ............................................................. 3-3
Cleaning............................................................................................................. 3-6
AC Fuse Replacement ....................................................................................... 3-7
DC Fuse Replacement ....................................................................................... 3-8
4 Performance Verification................................................................... 4-1
Introduction ....................................................................................................... 4-3
Configuring the Performance Test Setup ...................................................... 4-3
Initializing the Performance Test Setup ........................................................ 4-5
Accuracy Performance Tests ............................................................................. 4-6
Master Alarm Output Tests........................................................................... 4-7
RS-232 Master Alarm Output Test ........................................................... 4-7
Fluke DAQ Master Alarm Output Test .................................................... 4-7
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Contents
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