Analog Outputs - GE Optica Operator's Manual

Analog Outputs

Example:
Installation
Note: When the Optica is being programmed, the analog outputs
provide 4–20mA and 0–5 VDC signals representing the
designated parameters.
•
For 4–20mA output, connect to terminals labelled 4–20 (+) and
RTN (–).
Note: The maximum load allowed for current output is 500 Ohms.
•
For 0–5 VDC output, connect to terminals labelled 0–5 (+) and
RTN (–).
Note: The maximum load allowed for voltage output is 5 mA.
Assume a temperature output, scaled to range from 0°C (Tlower) to
100°C (Tupper), with a measured actual temperature of 23°C
(Tactual):
The voltage output is calculated by:
Vout =
yielding an output voltage of 1.15V.
(
-------------------- -
(
The current output is calculated by:
( )
Iout mA =
yielding an output current of 7.68 mA.
(
23 0
–
-------------------- -
(
100 0
( )
Tactual Tlower –
--------------------------------------------- -
( )
Tupper Tlower –
)
23 0
–
×
5 1.15V
=
)
100 0 –
( )
Tactual Tlower
–
--------------------------------------------- - ×
( )
Tupper Tlower –
)
× ( )
16 7.68mA
+ 4 =
)
–
January 2006
×
5
( )
20 4 + 4
–
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