Fluke 1522 - Manual (Page 53)

9 Calibration
The 1522 should be calibrated at regular intervals to ensure that it continues to
measure with proper accuracy. Calibration should only be done by qualified,
authorized personnel.
9.1 Required Equipment
The following items are required to test and calibrate the 1522:
• 0Ω four-wire resistor (short)
• 25Ω four-wire resistor, accurate within 20 ppm (±0.0005Ω)
• 100Ω four-wire resistor, accurate within 20 ppm (±0.002Ω)
• 400Ω four-wire resistor, accurate within 20 ppm (±0.008Ω)
• 4 kΩ four-wire resistor, accurate within 50 ppm (±0.2Ω)
• 10 kΩ four-wire resistor, accurate within 50 ppm (±0.5Ω)
• 40 kΩ four-wire resistor, accurate within 50 ppm (±2Ω)
• 100 kΩ four-wire resistor, accurate within 50 ppm (±5Ω)
• 500 kΩ four-wire resistor, accurate within 75 ppm (±37.5Ω)
Each resistor must be attached with an INFO-CON probe connector. The 25
Ω,
100
Ω, and 400Ω resistors must be programmed with the CVD probe type with
units set to ohms. The 4 k
Ω, 10 kΩ, 40 kΩ, 100 kΩ, and 500 kΩ resistors must
be programmed with the THERM probe type with units set to ohms.
9.2 Calibration Procedure
Calibration requires adjustment of the CAL1 and CAL2 parameters at 100
Ω
and 10 k
Ω respectively (see Section 7.9.20). The calibration parameters can be
accessed from the front panel by pressing the MODE button and holding it for
three seconds, releasing it, then pressing the ENT button (see Section 7.9). You
must enter the pass-code to continue (see Section 7.9.4). The step-by-step pro-
cedure is as follows:
1. Connect the 100
Ω resistor. Adjust the CAL1 parameter by subtracting the
measured error. For example, if the resistor is exactly 100.000
Ω and the 1522
measures 100.029
Ω, CAL1 should be adjusted by subtracting 0.029 from the
current value of CAL1.
2. Verify the accuracy at 0
Ω, 25Ω, 100Ω, and 400Ω.
3. Connect the 10 k
Ω resistor. Adjust the CAL2 parameter by subtracting the
measured error. For example, if the resistor is exactly 10.0000 k
Ω and the 1522
measures 10.0029 k
Ω, CAL2 should be adjusted by subtracting 2.9 from the
current value of CAL2.
53
9 Calibration
Required Equipment