The Analog Input Function is designed for practical process applications. The
complete design incorporates the display of variables on the
WinCC mimic, with variable attributes to display the state of the analog input.
It also includes the pop-up template, with detailed display of
the analog condition, values and properties. The Step7 function is easily
incorporated into an existing or new PLC project. Details of alarm
configuration will also be supplied.
Mimic Display : Analog values on-screen need to be discretely small, but with
properties, to display maximum detail. For this purpose we
have designed the on-screen values to reflect not only the analog value, but
also the state of the signal, i.e. warning (yellow) or alarm
Alarms and warnings are configured to flash on-screen on first occurrence.
This assists with drawing the attention to the problem area. Once
the alarm has been acknowledged, it will stop flashing and change to a steady
state of yellow (warning) or red (alarm).
Further information of each value will be made available when the operator
clicks on the Analog Tag, thereby opening the template
(example) as shown below :
1. Scaling is entered on the PLC function, this can be 0 to 100, -5 to +15,
or any scaling that your instrument requires. This scaling cannot
be modified from WinCC.
2. The display bar shows a graphical representation of the analog value, as a
filling bar from minimum to maximum value (bottom to top).
3. Current value displays the analog value as a scaled value in decimal format.
It is possible to have more or less decimal points displayed.
The units of display (in this case "%") is entered in a field
in WinCC. Other units could be e.g. "kg" or "kPa" etc.
This value changes colour when in warning (yellow) or alarm
4. Limit monitoring "ON" indicates that alarms will be activated if the
configured levels are exceeded. It is possible to disable alarms in the PLC.
5. As the template is opened, the correct tag name is displayed,
linking the displayed variable to its associated value. This value
is entered in a Datablock on the PLC.
6. Warning and alarm levels can be configured from the WinCC template. As
can be seen for the above example, 85.0 has been
configured as "Warning High" and 95.0 as "Alarm High". The
yellow and red bars at displays these levels in graphic format. It is also
possible to enter low alarms and warning levels. These fields
have their own access level control and can be protected to access by higher
level staff only.
7. When a new warning, or alarm state occurs, the signal will flash, indicating
an un-acknowledged alarm. Pressing "ACK" on the template will
acknowledge the alarm or warning.
8. Press PCE (higher level password required) to enter a forced value into the
reading. This is useful for testing, simulation, or in case an instrument
is faulty and the analog needs to be fixed to a known good
Use the ActiveX control below to find out more about the features of this
- Allows Scaling of any measured value in the PLC for display on WinCC
- Graphical and numeric representation of measured value
- Alarming can be enabled / disabled from the PLC
- Visual confirmation of tag name on display
- Visual representation of warning / alarm levels
- Warning / Alarm levels can be edited from WinCC (access level
- Mimic and template will visually indicate a new or acknowledged warning
- Starting time will delay monitoring of alarm conditions, e.g. ignore
alarms for 20 sec after pump starts
- Damping Time provides a filter to eliminate spurious alarms
- Hysteresis can be set to prevent an alarm going on/off on a slightly
fluctuating analog signal
- Multiple measurement entries into one datablock possible, i.e. doesn't
require a DB for each measurement
- Addressing is done directly to analog input card, e.g. IW124
- Various sensor types supported, V/I, Temperature (PT100, Type K, Type
J); Direct entry of a value is also possible
- Configurable upper and lower ranges for each signal
- Cyclic filtering possible, for smoothing each measured value seperately
- Alarming can be enabled / disabled from the PLC, e.g. only alarm on
low-flow if the pump is running
- Additional alarms available, e.g. measurement error, wire break, range
WHAT IS INCLUDED :
The Analog Input package includes the following :
Full step-by-step configuration and instruction manual.
Example mimic with analog input implementation
Usable Mimic display items. (copy/paste from example)
Structure tags in WinCC
Pop-up template (as WinCC .pdl files)
Full step-by-step instruction manual.
Example function and datablock with Analog Input implementation
Structured tag (UDT) for creating new datablocks
Analog Input Function (FC) for use in programming.