Fluke 1504 8 Calibration Procedure

8 Calibration Procedure

The 1504 uses a three-pointcalibration scheme with a quadratic polynomial

correction function to maintain the accuracyof its resistance measurement. The

three calibration points are at 0Ω,10kΩ, and 100 kΩ.Three calibration pa-

rameters determine the correction function:CAL0, CAL10, and CAL100.

The CAL0 parameter sets the correction at 0Ωresistance (but does not

affectthecorrectionat10kΩ). The CAL10 parameter sets the correction

at 10 kΩresistance (but does not affectthe correction at 0Ω).The

CAL100 parameter sets the correction at 100 kΩresistance (but does

not affectthe correction at 0Ωand 10 kΩ).Adjusting the calibration pa-

rameters directly affectsthe measurement at the specific resistances.

For example,increasing the CAL10 parameter by 0.1 increases the

measured value at 10 kΩby 0.1Ω.

The calibration parameters are accessed inthe Cal menu. Th e calibration pa-

rameters are protected by requiring thecorrect password to access them. Press

the Menu/Enter button,“SEt?” appears. Press the /Exit buttonand hold it

downfor one second, “CAL” appears briefly. The display will show “PA=

0000” and allowyou to change the number to the correct password. You must

enter thepassword (“4051”). Use the Land Rbuttons to move between

the passworddigits and the Uand Dbuttons to increase or decrease

the value of a digit.Press Enter when all the digits are correct. If the pass-

word is entered correctly the firstparameter in the calibration m enu will appear.

The firstparameter inthe Cal menu is the lockout control parameter, indicated

on the display as “LOCOUt”. This parameter has two options,“CAL”and

“ALL”. “CAL” (default) locks out the calibration menu only. “ALL” locks out

all menusand access to any menu requires the correct password. Use the L

and Rbuttons to select the lockoutoption and press Enter to continue.

The instrument calibration parameters follow.

The calibration parameters appear with thename shown briefly then the value.

Youcan change the sign and digits of each parameter. Use the Land R

buttons to movebetween digits and the Uand Dbuttons to increase or

decrease the value of thedigit. Press Enter to save the new value.

The calibrationparameters can also be set using remote commands through the

RS-232 or IEEE-488 interfaces.The *PA=<password><EOS> command must

be used first,using the correct password (“4051”), to enable access to the cali-

bration parameters. Lockoutprotection is automatically set by cycling the

power.The *C0=<value><EOS>, *C1=<value> <EOS>, and

*C2=<value><EOS>commands can be used to set the values of the CAL0,

CAL10, and CAL100 parametersrespectively.

8 Calibration Procedure

Accessing the Calibration Parameters