Automated Logic InterOP8500, Технические инструкции

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Revised 7/10/01 • InterOP8500 12 © 2001 Automated Logic Corporation
4. For each input, enter the point identifiers.
• In WebCTRL, enter the point number
and the point type on the Properties
page. For linear inputs, set the
minimum value and maximum value to
scale the point to engineering units.
• In SuperVision, enter the channel
number, offset, and gain using the
Configure Points or Point Help feature.
Valid channel numbers are listed in
“Channel Numbers in SuperVision” on
page 15.
5. To verify each input’s operation, have
each sensor create a known value and
compare it to the condition reported on
the FB’s Properties page in WebCTRL or
Status page in SuperVision.
Calculating Offset and Gain
You may need to calculate the offset and gain
for analog inputs to ensure the correct value
is read by the InterOP8500. You can also use
the custom translation table on the module
driver Parameter page to read nonlinear
signals from these inputs. Refer to the
“Channel Numbers in SuperVision” on
page 15 for details.
Use this formula to calculate the gain for an
analog input point:
Use this formula to calculate the offset for an
analog input point:
For example, consider a 1 to 4.5V humidity
sensor with a relative humidity of 20 to 90%.
The voltage span is 3.5 volts (4.5V - 1V). The
user unit span is 70% (90% - 20%). Calculate
the gain and offset for a humidity sensor like
this:
Here is an example of a 0 to 2.5V V-9012
feedback sensor with a range of 0 to 100%
relative humidity. The voltage span is 2.5V
(2.5V - 0) and the user unit span is 100%
(100% - 0%). Calculate the gain and offset for
a V-9012 feedback sensor like this:
Binary I/O Power Jumper
The InterOP8500 provides a jumper (see
Figure 1 on page 2 for location) for selecting
between internal and external power for
Binary I/O points. The InterOP8500 provides
isolation for externally powered devices and
no isolation for internally powered devices. If
binary outputs are present, they must be
externally powered and the jumper must be
set to the External position (see Figure 15 on
page 13). If no binary outputs are present,
GAIN = user unit
256 voltage span
5 volts
*
256 minimum voltage
OFFSET = GAIN
5 volts
*
*
*
5 volts
* 256 1 volt
OFFSET = 0.392 *
= 0.392 51.2
= 19.07
GAIN = 70%
256 3.5 volts
5 volts
*
= 70% 178.5
= 0.392
*
= 0.392 0
256 0 volts
5 volts
*
OFFSET = 0.78
*
= 0
GAIN = 100%
5 volts
256 2.5 volts
*
= 100% 127.5
= 0.78