Yokogawa JUXTA MS5 - Manual (Page 5)

5 IM 77J04S05-01E 1st Edition Jul 29, 2005-00
7. MAINTENANCE
The product starts running immediately when the power is turned on;
however, it needs 10 to 15 minutes of warm-up before it meets the
specified performance.
7.1 Calibration Apparatus
● Two 6-dial variable resistor (Yokogawa M&C 279301 or the equivalent)
● A digital mutimeter (Yokogawa 7561 or the equivalent)
● A precision resistor of 250
Ω ±
0.01%, 1 W
● A setting tool for adjustment
(Refer to “4.2 Connector for Communication” in this mnual.)
7.2 Calibration Procedure
(1) Connect the instruments as shown below.
(2) Operate the variable resistor corresponding to the specifications
of the potentiometer to be combined (overall resistance, resis-
tance of 0% and 100%). Change the values of R1 and R2 main-
taining the overall resistance constantly, and apply the input sig-
nal equivalent to 0, 25, 50, 75 and 100% of the input span to the
converter.
(3) Check to see the corresponding output voltages are 0, 25, 50, 75,
and 100% respectively and within the specified accuracy rating.
“R” is used for current output.
● Use the setting tool (VJ77 Parameter Setting Tool or JHT200
Handy Terminal) or the switches on the front panel (selection
switch and adjustment switch) to adjust the input/output signals.
Input Adjustment Procedure
Refer to “4.3.2 Setting Input Range Using the Switches on the
Front Panel” and “5.2 Setting Input Range” for the input adjust-
ment.
NOTE
It is recommended that you use the potentiometer actually
used for inputs in the field when the input adjustment is
performed.
Because some differences occur compared with the test
inputs using the 6-dial variable resistor owing to the
influence of the tolerance of potentiometer resistance and
wiring resistance.
The accuracy may not be maintained if you use the
potentiometer actually used for inputs after performing the
input adjustment by test inputs.
Output Adjustment Procedure
(1) When adjusting 0% value of output, call the adjustment item (P:
ADJUST) to select P26: OUT1ZERO ADJ.
(2) If it slips out to (
+
) side, set (
−
) value equivalent to slipout; if slips
out to (
−
) side, set (
+
) value equivalent to slipout.
*: The 100% value of output can be adjusted by the same operation
as the above.
For adjustment using a setting tool, refer to the User’s Manual for
each setting tool and “6. List of Parameters” in this manual.
For adjustment using the switches on the front panel, refer to “4.3
Selection Switch and Adjustment Switch.”
User’s Manual for VJ77 [Document No.: IM 77J01J77-01E]; how-
ever, use the VJ77 of version R1.04 or later.
User’s Manual for JHT200 [Document No.: IM JF81-02E]
1
2
R1
100%
0%
R2
6
7
8
3
4
5 L +
N −
GND
R
−
+
Power supply
Input
Output
R: 250 Ω precision resistor
for current output
Digital
multimeter
6-dial variable
resistor
6-dial variable
resistor