Ametek XEL Serie Mode D'emploi page 51

Routine calibration is carried out without opening the instrument. Allow a 10 minutes warm-up
before commencing calibration.
Equipment Required
A 5½ digit multimeter with better than 0.02% accuracy on dc volts and better than 0.06%
accuracy on dc current (to 5A). Alternatively use a precision shunt for current measurement.
Calibration
Calibration mode is entered by holding down all three VOLTAGE SPAN keys (V
ENABLE) while the POWER switch is turned on (
indicator lamps will be lit, as a display test. When the VOLTAGE SPAN keys are released the
display will show the first calibration step and the ENABLE lamp will blink slowly.
In calibration mode V
max
each step the calibration must first be made 'active' by pressing the ENABLE key; the ENABLE
lamp blinks rapidly when calibration is active and the calibration value is adjusted using the MAIN
and FINE VOLTAGE controls. If ENABLE is not pressed at any step, calibration is not activated
at that step and the existing calibration value is retained when the step is exited.
During calibration the left-hand display shows the calibration value and the right-hand display
shows the step number. Some values are 5-digit, in which case the 5
hand digit of the right-hand display.
Some steps adjust values on the display and some adjust the output. When a step adjusts the
output, measured by the DMM, the left-hand display shows a number.
Calibration must be done in sequence. However, it is possible to pass through a step, without
making an adjustment, providing ENABLE is not pressed, see above.
The full procedure is detailed in the table. Steps 3 and 8 are model dependent; note that the
15V/5A model is calibrated at 3A to minimize errors.
Note that the CURRENT control must be at minimum for step 5.
The message between steps 7 and 8 is the point at which the high current
change load
range must be selected on the DMM.
The final step in the sequence (step 14) shows
stores the new calibration values and reboots the instrument in the normal operating mode. Until
this is done the new values are not stored permanently. Turning POWER off (
will retain all the old calibration values.
l
). All the display segments and other
steps forward to the next adjustment and V
. Pressing the ENABLE key for 2½ seconds
End
Calibration
, V and
min max
steps backwards. At
min
th digit is shown in the left-
) at any point
(Calibration Table below)
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