Rs-232 Calibration (Manual) - Tektronix DMM4020 Technical Reference Manual

When the last calibration point for the selected function finishes, the Meter will go to
IDLE mode where  appears in the secondary display and six flashing dashes appear
in the primary display. Return to step 1 above and select the next function for calibration.
Press to exit the calibration mode at any time. If a function has not been completely
calibrated, a CAL ERROR will be displayed.

When
input.
When in current calibration, if ZERO point is calibrated all test leads shall
be removed. Use the mA input terminal for low current range (1, 2, 3, and 4
for ADC and 1 or 2 for AAC). Use the 10A input terminal for high current
range (5 or 6 for ADC and 3 or 4 for AAC).
Set the calibrator to 1.9 volts for frequency calibration input.

RS-232 Calibration (Manual)

A manual calibration of the Meter is possible by typing commands through the RS-232
port from a PC and making manual adjustments of the test equipment. To use the RS-232
port to calibrate the Meter, connect a PC to the Meter using a null-modem cable. Set the
PC in the Hyper Terminal mode to enable communication between the PC and the Meter.
All commands should be ASCII codes.
Enable calibration by sending "*TER" to the Meter. The Meter will return "Select a
Function or input EXIT to QUIT!".
1. Send "VDC", "VAC", "ADC", "AAC", "OHMS", or "FREQ" to the Meter to select the
function you want to calibrate. The Meter will return "XXXXXX V, 0 HZ" where
XXXXXX is the recommended calibration value. The value also shows in the Meter
display.
The recommended value can be overwritten by sending the Meter a
new value as "CALREF XXXXXX". If the value is acceptable
"=>" will be returned, otherwise "!>" will be returned.
2. Push the "Enter" key to confirm the calibration value.
3. With a stable input to the Meter, push the "Enter" key to start calibrating the current
calibration point. The Meter will return the string "WAIT..." while calibrating.
When the calibration point finishes calibration and another calibration point is part of the
selected function, a new recommended calibration value is sent automatically. Input the
proper signal and repeat step 3 above.
Once a function is selected for calibration, all calibration points must be
calibrated before exiting the calibration process. Otherwise a CALL
ERROR will show in the display.
When the last calibration point for the selected function finishes, the Meter will go to
IDLE mode and the Meter will send the string "Select a Function or input
EXIT to QUIT!". Return to step 1 above and select the next function for calibration.
Note
shows in the display, 4-wire compensation is enabled on the
Note
Note
Note
Note
Note
Performance Verification and Calibration
Adjustment (Calibration)
3
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