Phonetics Sensaphone SCADA 3000, Руководство пользователя

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• Do not run signal or communications wiring and power in the same conduit.
• Segregate I/O wiring by signal type. Bundle wiring with similar electrical charac
-
teristics together.
• Allow at least two inches between the module and I/O wiring ducts.
The three terminal blocks on the Analog Output Module are all removable for faster and more
convenient wiring of the I/O module. They should only be removed or attached when power
to the module is OFF. To remove the terminal blocks use your thumb or forefinger to push the
screw section of the terminal block straight out (see figure below) .
Figure 9: Removing terminal blocks
HOW THe ANALOG OUTPUT mODULe WORKS
The Analog Output Module has four independent outputs that can be used to control equip-
ment, drive digital displays, or provide information to other computer devices. The only
requirement is that the equipment be capable of accepting a 4–20mA, 0–20mA or 0–10V sig-
nal. The SCADA 3000 CPU sends information to the module telling it how much current or
voltage to drive to each of the outputs. The output levels are determined based on the control
program you create using the Ladder program, C-program or PID settings. The SCADA 3000
Software allows you to set up a custom table to scale the signal to units that describe your pro-
cess. For example, say you are using an output to control the position of a valve. In this case
4mA may represent a valve that is 0% open and 20mA may equate to 100% open. By setting
low and high table values of 0 and 100 respectively, you can now control the position of the
valve from 0 to 100% as opposed to 4–20mA. This can greatly simplify programming as well
as viewing the position of the valve from the software. For more information, see the SCADA
3000 CPU manual.
To program the Analog Output Module, click on the
Analog Output
icon on the Main Unit
form. The icon appears at the corresponding module address and is designated by the letters
“ AO .”
On the I/O Setup tab you can force output values by entering numbers in the Forced Status
fields. To remove a forced value, simply delete the number from the forced value field.
On the
Table and Cal
tab you can enter the table values that correspond to the 4mA and 20mA
signal outputs. The Offset is used to calibrate the output by adding or subtracting this value to
the output.
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SCADA 3000 User’s Manual