Fluke NetDAQ 2640A, Service Manual

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NetDAQ
Service Manual
4-28
There are two connection methods used between the leads from the instrument Universal
Input Module and the 5700A Calibrator. The volts dc, volts ac, and resistance functions
use the two-wire connection shown in Figure 4-7. The resistance function uses the four-
wire connection shown in Figure 4-8.
Ending Calibration 4-33.
When you are using the manual method of calibration and have completed the
calibration of the desired functions (dc volts, ac volts, ohms, and frequency), press the
front panel CAL Enable button again to clear CAL from the primary display. When
using the calibration features of NetDAQ Logger for Windows, calibration is ended
automatically when you exit the calibration mode.
RS-232 Instrument Configuration Parameters 4-34.
When CAL is shown in the primary display indicating you are in the calibration mode,
the instrument configuration parameters are set as listed in Table 4-2.
Table 4-2. RS-232 Instrument Configuration for Calibration Procedures
Parameter Setting
Channel Configuration Unique to calibration step
Reading Rate Slow
Trigger Type All disabled
Intervals All disabled
Drift Correction Enabled
External Trigger Output Disabled
Temperature Units Celsius
Queue Overflow Mode Discard old
Totalizer Debounce Disabled
Autodisable Scanning On
Calibration Procedure (Automatic) 4-35.
Automatic calibration uses Fluke MET/CAL software. All procedures are provided in
the MET/CAL Users Manual. These procedures assume you have completed the
“Preparing for Calibration” procedure above.
Calibration Procedure (Semiautomatic) 4-36.
Semiautomatic calibration uses the calibration feature built into the NetDAQ Logger for
Windows software. This procedure assumes you have completed the “Preparing for
Calibration” procedure above.
Complete the following procedure to calibrate an instrument using NetDAQ Logger for
Windows software. This procedure integrates the four calibration cycles: VDC, VAC,
ohms, and frequency. Complete only the cycle or cycles of interest.
1. If you have not already done so, complete the “Preparing for Calibration” procedure
earlier in this chapter. Note the instrument baud rate and host computer COM port
used for interconnection.