YOKOGAWA CA71 HANDY CAL, Руководство пользователя

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IM CA71-E
10-5
Method of Calibrator
Adjustment
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App
NOTE
• Saving to memory results in the overwriting of existing data.
Be extremely careful since the previous adjustment setpoints are cleared.
• Both the thermocouple and RTD ranges are adjusted at the same time
when the 100 mV and 400 Ω ranges are adjusted.
TIP
With the CAL mode selected, press the key while holding down
the key. This key operation cancels the CAL mode (the same key
operation as for selecting the CAL mode).
You can use the same key operation to cancel the CAL mode during
adjustment, before saving to memory.
CAUTION
Precautions when adjusting the 400 Ω range for resistance signal source
(1) Internal Offset Adjustment
When setting a resistance of 0.00 Ω , make sure the voltage between
the H and L terminals is within ±20 µV. If the voltage is beyond the limits,
internal adjustments must be made. Contact the vender from which you
purchased the instrument.
(2) Notes on Resistance-measuring Current
Adjusting the 400 Ω range requires drawing two types of resistance-
measuring current – 1 mA and 5 mA – from an external device.
Adjust the range separately for each of these currents.
Adjustment for 1 mA
This adjustment is possible with the resistance measuring range of
the calibration standard (digital multimeter). At this point,
make sure the resistance-measuring current is 1 mA.
Adjustment for 5 mA
Like the method of adjusting the 400 Ω/5 mA range shown in the figure
(Hook-ups for Adjustment) on page 10-3, you can make this adjustment
by applying the reference current of 5 mA from the external device and
then measuring the resulting voltage drop.
10.2 Adjusting source Functions