Omega RD200 - Manual (Page 126)

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21. MAINTENANCE 21.3 Measured Values Check
3
Connections
Connections depend upon the input types. Connect both standard and other tools to the measuring input
terminals to be adjusted.
In order to prevent electric shock, turn off the power source before starting connections.
(1) In case of thermocouple input
The electromotive force of the thermocouple input is reduced by an amount proportional to the temperature
at the terminals. The recorder itself compensates (reference junction compensation) for this reduction. The
adjustment is executed by inputs based on the reference electromotive force (0
°C reference). In case the
“RJ selection” is set to “1” (Enable) in the “Range/Printing range” programming, an amount equivalent to the
reference junction compensation has to be subtracted using a reference junction compensator.
(2) DC voltage input (3) Resistance thermometer input
4
Checking Method
Input the printing range (T) of 0%, 50% and 100% from a
standard tool and obtain an error (e) by reading the
measured values (M).
e (%) = X 100
Error computation
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(B)
(A)
(B)
*Thermocouple of the same
type as the input type
Input terminals
1 2 3 4
( - )
(+)
Thermocouple wire * Copper lead wire
Test tube
Vacuum bottle
Ice + distilled water
Silicon oil
Reference junction
compensator
DC standard voltage
generator
Standard variable
resistor
Input terminals
1
2 3 4
Input terminals
1
2 3 4
Standard variable
resistor
M – T
T
Turn off the power source before starting connections Caution