16-6
Calibration
Model 6485 Instruction Manual
Aborting calibration
You can abort the calibration procedure at any time by pressing the EXIT key.
Current calculations
When calibrating the 2nA-2
µ
A current ranges, you must calculate the actual current val-
ues from the applied calibrator voltages and the characterized Model 5156 Calibration
Standard resistor values. Calibration currents are calculated as follows:
I = V/R
Where: I = required calibration current
V = calibrator voltage
R = actual standard resistor value
For example, assume you are calibrating the 20nA range using a 2V calibrator voltage
with an actual 100.5M
Ω
standard resistor value. The actual calibration current is:
2V/100.5M
Ω
= 19.9005nA.
Calibration procedure
The calibration procedure should be performed in the following order:
•
Preparing for calibration
•
Offset voltage calibration
•
Current calibration
•
Entering calibration dates and saving calibration
•
Locking out calibration
Preparing for calibration
1.
Turn on the Model 6485 and the calibrator, and allow them to warm up for at least
one hour before performing calibration.
2.
Press MENU, select CAL, then press ENTER. The instrument will display the fol-
lowing:
CAL: VOFFSET
3.
Use the up or down RANGE key to display the following:
CAL: UNLOCK
4.
Press ENTER. The instrument will prompt for the calibration code:
CODE? 000000
Summary of Contents for 6485
Page 20: ......
Page 24: ......
Page 44: ...1 20 Getting Started Model 6485 Picoammeter Instruction Manual ...
Page 66: ...3 6 Measurements Model 6485 Picoammeter Instruction Manual ...
Page 138: ...9 20 Remote Operation Model 6485 Picoammeter Instruction Manual ...
Page 159: ...11 CommonCommands ...
Page 164: ...11 6 Common Commands Model 6485 Picoammeter Instruction Manual ...
Page 165: ...12 SCPISignalOriented MeasurementCommands ...
Page 190: ...14 12 SCPI Reference Tables Model 6485 Picoammeter Instruction Manual ...
Page 214: ...16 14 Calibration Model 6485 Instruction Manual ...
Page 219: ...A Specifications ...
Page 221: ...B StatusandErrorMessages ...
Page 227: ...C GeneralMeasurement Considerations ...
Page 233: ...D DDCEmulationCommands ...
Page 247: ...E ExamplePrograms ...
Page 250: ...E 4 Example Programs Model 6485 Picoammeter Instruction Manual ...
Page 251: ...F IEEE 488BusOverview ...
Page 266: ...F 16 IEEE 488 Bus Overview Model 6485 Picoammeter Instruction Manual ...
Page 267: ...G IEEE 488andSCPI ConformanceInformation ...
Page 311: ......