Yokogawa EJA110A User Manual

Page 58

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IM 01C21B01-01E

9-2

9. MAINTENANCE

Table 9.2.1 Instruments Required for Calibration

Name

Remarks

Yokogawa-recommended Instrument

Power

supply

Model SDBT or SDBS distributor

Load

resistor

Model 2792 standard resistor [250

±

0.005%, 3 W]

Load adjustment resistor [100

±

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.)

±

(0.2% of rdg + 0.1% of F.S.)

2) For 130 kPa class

Accuracy:

±

0.02% of rdg

±

5digits

±

(0.2% of rdg + 0.1% of F.S.)

3) For 700 kPa class

Accuracy:

±

(0.02% of rdg + 3digits)

±

5 digits

±

(0.2% of rdg + 0.1% of F.S.)

4) For 3000 kPa class

Accuracy:

±

(0.02% of rdg + 10 digits)

±

(0.2% of rdg + 0.1% of F.S.)

5) For 130 kPa abs class

Accuracy:

±

(0.03% of rdg + 6 digits)

4 to 20 mA DC signal

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.

Pressure

source

Model 6919 pressure regulator (pressure pump)

Pressure range: 0 to 133 kPa {1000 mmHg}

Prepare the vacuum pump
for negative pressure
ranges.

Dead weight gauge tester 25 kPa {2500mmH

2

O}

Accuracy:

±

0.03% of setting

Select the one having a
pressure range close to
that of the transmitter.

T0901.EPS

for 0 to 10 kPa
for -10 to 0 kPa

for 25 to 130 kPa
for 0 to 25 kPa
for -80 to 0 kPa

for 100 to 700 kPa
for 0 to 100 kPa
for -80 to 0 kPa

for 0 to 3000 kPa
for -80 to 0 kPa

for 0 to 130 kPa abs

. . . . .

. . . . . . . . .

. . . . . . . . . . . . . . . . . . . . . .

. . . . . . . . . . . . . . . . . . . . . . . . . .

. . . . . . . . .

. . . . . . . . . . . . .

. . . . . . . . . . . . . . . . . . . . . . . . .

. . . . . . . . .

. . . . . . . . . . .

. . . . . . . . .

. . . . . . . . . . . .

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% level, there are
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,

250

Load
adjusting
resistance,
100

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,

250

Load
adjusting
resistance,
100

Digital voltmeter

Power
supply
E

F0901.EPS

Figure 9.3.1 Instrument Connections

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