Yokogawa EJA310E User Manual
Page 41
<8. Maintenance>
8-2
IM 01C25B01-01E
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
±5digits. . . . . . . . . . . . . . . . . . . . . . . . . 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.
Dead weight gauge tester 25 kPa {2500 mmH
2
O}
Accuracy: ±0.03% of setting
Select the one having a
pressure range close to that
of the transmitter.
Pressure
source
Model 6919 pressure regulator (pressure pump)
Pressure range: 0 to 133 kPa {1000 mmHg}
Prepare the vacuum pump
for negative pressure
ranges.
Note: The above table contains the instruments capable of performing calibration to the 0.2% level. Since special maintenance and
management procedures involving traceability of each instrument to higher-level standards are required for calibration to the 0.1%
or higher level, there may be difficulties in calibration to this level in the field. For calibration to the 0.1% level, contact Yokogawa
representatives from which the instrument was purchased or the nearest Yokogawa office.
V
R
Rc
P
Using pressure
generator
Reference pressure
High pressure side
High pressure side
Low pressure side
open to atmosphere
Low pressure side
open to atmosphere
Supply pressure
Pressure generator
Load resistance,
250Ω
Load
adjusting
resistance,
100Ω
Digital voltmeter
Power
supply
E
V
R
Rc
P
Using pressure
source with
manometer
Reference pressure
Pressure source
Model MT220
precision digital manometer
Load resistance,
250Ω
Load
adjusting
resistance,
100Ω
Digital voltmeter
Power
supply
E
F0801.ai
Figure 8.1
Instrument Connections (EJX110A)