Руководство - руководство по программированию в среде U90 Ladder (англ.язык)
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Inverted Coil
An Inverted Coil represents the opposite result instruction of the conditions (contacts and/or function blocks) on
the Ladder net before the Inverted Coil. An Inverted Coil instruction can be:
Output
Memory Bit
System Bit
The result instruction can be to an external output device (for example: alarm bell) or to an internal system
element (for example: SB 80 activate linearization).
During the system scan, the processor evaluates all of the program elements on the Ladder net before the
Inverted Coil for power flow continuity.
If no power flow continuity exists in the net: the Inverted Coil address instruction is ON (logic 1).
If power flow continuity exists in the net: the Inverted Coil address is OFF (logic 0).
Set Coil
A set coil separates the coil from the action or condition that energized the coil. Once energized, a set coil's
result is no longer dependant on the action that energized it. A set coil stays energized (latched) until its
condition is reset (unlatched) by a reset coil.
A set coil can be:
Memory Bit
System Bit
Output
An example of a set coil is an overhead light. When we turn on a light it stays lit until we turn it off (reset or
unlatch it) or the light bulb burns out. Luckily, you do not have to hold the light switch to keep the light on.
An example of a coil that you do not want to be set (latched) is a car horn. You expect it to toot only when you
press on the horn button and you expect it to stop when you stop pressing on the horn button.
Use set and reset coils to preserve a condition in a program.
Reset Coil
A reset coil turns off (unlatches) a set coil, provided that there is logic continuity to the reset coil. Once a set coil
is energized it stays energized, independent of the original set condition, until a reset coil with the same address
resets (unlatches) the coil condition.
A reset coil can be:
Memory Bit
System Bit
Output
Do not use a set coil without a reset coil in a program.
Operands
An element's Operand is the form in which information is stored and operated on in the U90 Ladder program.
Operand lists are organized in categories, according to operand type:
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Input: I (according to model and expansion)
Output: O (according to model and expansion)
Memory Bit: MB (0 - 255)
Memory Integer: MI (0 - 255)
System Bit: SB (0 - 255)
System Integer: SI (0 - 255)
Timer:T (0 - 63)
Every Operand has an Address and a Symbol.
Symbols appear together with the operand every time the operand and address are used in the program. There
are two types of symbols: preset and user-created.
Preset symbols are descriptions that are connected to System Bits and System Integers.
User-created symbols are descriptions that are written by the user for a specific project
application. The user assigns a particular description to a particular operand.
Power-up
You can assign Power Up values to most Data Types. These values are written into the operand by the program
when the controller is turned on. Outputs, MBs, SBs can be set or reset; integer values can be written into MIs
and SIs.
You can assign Power Up values when you place an element into a net, or by opening a Data Type list as shown
below.
Note •
If an operand has been assigned a Power-up value, it is a referenced operand and will not appear
in the Unreferenced Operand list.
Watch Folders
Watch Folders enable you to:
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Arrange related groups of operands in folders.
Name the folders.
View these operands in the Output Window at the bottom of the screen.
To view a Watch folder, click it in the Program Navigation window. Edit the folder by right-clicking a line, then
selecting the appropriate function.
To add a single operand to a Watch folder, right-click it in the Ladder or in the Operand Output Window.
Operand Addressing
An Operand Address is the physical location in the PLC memory where the element information is stored.
For example:
MB 10 - "10" is the address of the MB Operand
MI 35 - "35" is the address of the MI Operand
T 12 - "12" is the address of the Timer Operand
U90 Ladder allows you to create your own symbols before you write your program. This feature can help you to
organize your project properly from the very beginning. You can also create symbols as you write your program.
Symbols can be edited after you create them. Note that there is a default address setting for each operand type.
The Default message box will appear if you do not specify an address:
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Inputs (I)
Inputs are one Operand type available for writing a project application.
The number of Inputs varies according to the PLC model and any I/O Expansion Modules that may be
integrated into the project.
An Input is an actual hardwired input connection into the controller.
Click on the Inputs folder in the Program Navigation pane to display the complete list of Inputs. Scroll down to
view the complete list
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Outputs (O)
Outputs are one Operand type available for writing a project application.
The number of Outputs varies according to the PLC model and any I/O Expansion Module integrated into the
project.
An Output is an actual hardwired output connection from the controller.
Click on the Outputs folder in the Program Navigation pane to display the complete list of Outputs. Scroll down
to view the complete list
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Timers (T)
U90 Ladder offers 64 On Delay Timers. Timers have a preset value, a current value, and a bit value. Timers
always count down from the Preset Value. The timer value is 14 bits.
Click on the Timers folder in the Program Navigation pane to display the complete list of Timers. Scroll down
to view the complete list.
To place a Timer in your program, place a direct coil in a net, and select T.
Timer resolutions
10mS (0.01S)(from 00:00:00.01 to 00:02:43.83 )
100mS (0.1S)(from 00:00:00.10 to 00:27:18.30)
1000mS (1.0S)(from 00:00:01.00 to 04:33:03.00 )
10000mS (10.0S)(from 00:00:10.00 to 45:30:30.00)
The first 14 bits (from the LSB) of the Timer register contains the value. The two most significant bits contain
the Timer resolution.
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Note that:
A Timer value can be displayed in a Display as a current or elapsed value/
The Resolution field is Read-only. The resolution is a function of the Timer Preset Value.
You cannot change the resolution of a timer when the application is running.
A timer's current value can be changed at any time, including when the timer is active. The new
value can be either greater or smaller than the previous value; storing 0 into a timer's current
value stops it immediately.
A change of Timer Preset value without changing the resolution will take effect when the timer
restarts.
Changing the resolution of the timer's preset value does not affect the current resolution; it is
therefore recommended that the resolution not be changed while the timer is active.
During Stop mode, timers continue to run.
Memory Bits (MB)
Memory Bits are one Operand type available for writing a project application.
There are 256 MBs (Address MB 0 - MB 255).
Memory Bits hold a bit value ( 0 or 1).
Click on the Memory Bits folder in the Program Navigation pane to display the complete list of Memory Bits.
Scroll down to view the complete list
Memory Integers (MI)
Memory Integers are one Operand type available for writing a project application.
There are 256 MIs (Address MI 0 - MI 255).
Memory Integers hold an integer value ( -32768 to +32767).
Click on the Memory Integers folder in the Program Navigation pane to display the complete list of Memory
Integers. Scroll down to view the complete list
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System Bits
System Bits are the Operating System interface to the user writing the application. System Bits are reserved by
the Operating System for particular functions. Some System Bits, for example, are connected to the PLC's
keypad keys.
There are 256 SBs (Address SB 0 - SB 255).
Only certain SBs may be written into by the programmer:
SB 80: Activate Linearization
SB 200 -SB 215: M90 Network Operand
Click on the System Bits folder in the Program Navigation pane to display the complete list of System Bits.
Scroll down to view the complete list
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System Integers (SI)
System Integers are the Operating System interface to the user writing the application. System Integers are
reserved by the Operating System for particular functions. Specific System Integers, for example, are connected
to the M90's high speed counter/shaft-encoder.
There are 256 SIs (Address SI 0 - SI 255).
Only certain SIs may be written into by the programmer:
SI 2: Current HMI Display
SI 80 - SI 84: Linearization Parameters
SI 200 , SI 201: M90 Network Operand
Click on the System Integers folder in the Program Navigation pane to display the complete list of System
Integers. Scroll down to view the complete list
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Assigning an Operand Address by Symbol
1. After placing the element on the net, the Select Operand and Address dialog box opens.
2. Click on the Symbol drop-down menu.