Fluke 2625A User Manual

Page of 310
HYDRA
Service Manual
4-24
Note
The 300 k
Ω
, 3 M
Ω
, and 10 M
Ω
 ranges are sensitive to noise. Any
movement of the input leads can cause noisy readings. Use shielded leads
and verify these two calibration points at the conclusion of calibration.
Table 4-10. AC Volts Calibration
Command
Response
Action
CAL 2
=>
Puts Hydra in VAC Calibration.
CAL_REF?
+029.00E-3
You output 29 mV ac at 1 kHz from the 5700A. Wait about 8 seconds.
CAL_STEP?
Hydra computes calibration constant 7 and returns the calibrated reading
(for example, +029.00E-3.)
Note
If the input is incorrect, the "!>" response signifies that a Device
Dependent Error was generated. The calibration step could not be
executed. Verify that the input to Hydra channel 1 is the correct value and
polarity. Also verify that the 5700A is in OPERATE mode. If the input is
correct, Hydra may require repair.
CAL_REF?
+290.00E-3
You output 290 mV at 1 kHz from the 5700A. Wait 8 seconds.
CAL_STEP?
Hydra computes calibration constant 8 and returns the calibrated reading.
CAL_REF?
+0.2900E+0
You output 290 mV at 1 kHz from the 5700A and wait 8 seconds.
CAL_STEP?
Hydra computes calibration constant 9 and returns the calibrated reading.
CAL_REF?
+2.9000E+0
You output 2.9V at 1 kHz from the 5700A and wait 8 seconds.
CAL_STEP?
Hydra computes calibration constants 10 and 11 and returns the
calibrated reading. (For software versions lower than 5.4, this step
computes calibration constant 10 only.)
CAL_REF?
+29.000E+0
You output 29V at 1 kHz and wait 8 seconds.
CAL_STEP?
Hydra computes calibration constants 12 and 13 and returns the
calibrated reading. (For software versions lower than 5.4, this step
computes calibration constant 11 only.)
CAL_REF?
+290.00E+0
You output 290V at 1 kHz and wait 8 seconds.
CAL_STEP?
Hydra computes calibration constant 14 and returns the calibrated
reading. (For software versions lower than 5.4, this step computes
calibration constant 12.)
4-28.  Reference Junction Calibration
Note
This procedure is necessary only if the Input Module has been repaired or
damaged, or if R3 on the Input Module has been inadvertently adjusted.
If thermocouple readings taken in the Thermocouple Temperature Accuracy Test section
of the performance tests are found to be out of tolerance, the Input Module Reference
Junction may require calibration. First, check the volts dc calibration. If volts dc
calibration is correct, perform the following steps:
1.
 
Perform the Volts DC group calibration.
2.
 
Switch OFF power to Hydra, and remove the Input Module from the rear of the
instrument.