<8. Maintenance>
8-2
IM 01C25W05-01EN
Table 8.1
Instruments Required for Calibration
Name
Yokogawa-recommended Instrument
Remarks
Power supply Model SDBT or SDBS distributor
4 to 20 mA DC signal
Load resistor
Model 2792 standard resistor [250 Ω ±0.005%, 3 W]
Load adjustment resistor [100 Ω ±1%, 1 W]
Voltmeter
Model 2501 A digital multimeter
Accuracy (10V DC range): ±(0.002% of rdg + 1 dgt)
Digital
manometer
Model MT220 precision digital manometer
1) For 10 kPa class
Accuracy: ±(0.015% of rdg + 0.015% of F.S.). . . . for 0 to 10 kPa
±(0.2% of rdg + 0.1% of F.S.). . . . . . . . for -10 to 0 kPa
2) For 130 kPa class
Accuracy: ±0.02% of rdg. . . . . . . . . . . . . . . . . . . . for 25 to 130 kPa
±5 digits . . . . . . . . . . . . . . . . . . . . . . . . for 0 to 25 kPa
±(0.2% of rdg + 0.1% of F.S.). . . . . . . . for -80 to 0 kPa
3) For 700 kPa class
Accuracy: ±(0.02% of rdg + 3digits) . . . . . . . . . . . for 100 to 700 kPa
±5 digits . . . . . . . . . . . . . . . . . . . . . . . . for 0 to 100 kPa
±(0.2% of rdg + 0.1% of F.S.). . . . . . . . for -80 to 0 kPa
4) For 3000 kPa class
Accuracy: ±(0.02% of rdg + 10 digits). . . . . . . . . . for 0 to 3000 kPa
±(0.2% of rdg + 0.1% of F.S.). . . . . . . . for -80 to 0 kPa
5) For 130 kPa abs class
Accuracy: ±(0.03% of rdg + 6 digits) . . . . . . . . . . . for 0 to 130 kPa abs
Select a manometer having
a pressure range close to
that of the transmitter.
Pressure
generator
Model 7674 pneumatic pressure standard for 200 kPa {2 kgf/cm
2
}, 25 kPa
{2500 mmH
2
O}
Accuracy: ±0.05% of F.S.
Requires air pressure
supply. Select the one
having a pressure range
close to that of the
transmitter.
Dead weight gauge tester
Accuracy: ±0.03% of setting
Pressure
source
Prepare the vacuum pump
for negative pressure
ranges.
