Beckhoff Device¶
Documentation from the Advanced Electronics group:
Communication Patterns¶
For simplicity, Karabo mirrors the structure of the PLC’s soft-devices in multiple Karabo devices.
These are proxies of the PLC status, as viewed by the TCP interface.
The PLC does not send each single updates happening on the Hardware to the TCP layer, but applies the following data reduction strategies:
- Event driven/Epsilon: the soft-device will send a specific value only in case that a change is larger than a fixed threshold (e.g. temperature for temperature sensors, position for motors)
- Scheduled push: The soft-device can be programmed to send periodic updates.
- Polling: Explicit request of an attribute in a defined time interval. This mode of communication is inefficient with respect to the PLC and network load and should therefore be used for debugging purposes only.
Common Properties¶
Epsilon¶
The epsilon is void for many device classes (e.g. Boolean properties..). In the devices which use epsilon it is used for one property only. E.g. Motor: position, AnalogIn: Value.
“Throttling” of fast changing properties¶
The maximum update rate coming from each Soft device can be set using the
property Maximum Update Frequency
Each device can be included in a technical interlock implementation. This Karabo device is capable of decoding the information coming from the PLC. More information is available the section Interlock. .. _BeckhoffGeneric:
Commands¶
| Key | Displayed Name | Alias | Access Level | Allowed States | Description |
|---|---|---|---|---|---|
| reset | Reset | CError | USER | ERROR, INTERLOCK_BROKEN | Resets the PLC hardware |
| readHardware | Read | EXPERT | Requests value updates from the PLC for the properties listed under ‘Properties to read’ | ||
| requestHardwareValues | Request hardware values | CSendAll | EXPERT | Ask for all property values on the device | |
| CReInit | Reinit | CReInit | ADMIN | Reinitialize device | |
| disableInterlockedSlots | Disable Interlocked Slots | ADMIN | INTERLOCK_BROKEN | Send device into INTERLOCKED state, thus enabling all interlocked slots. | |
| enableInterlockedSlots | Enable Interlocked Slots | ADMIN | INTERLOCKED | Send device into INTERLOCK_BROKEN state, thus enabling all interlocked slots. |
Properties¶
| Key | Displayed Name | Alias | Type | Access Level | Access Mode | Allowed States | Description |
|---|---|---|---|---|---|---|---|
| beckhoffComDevice | BeckhoffCom Device | String | OBSERVER | READONLY | InstanceId of the BeckhoffCom device that forwards commands to the PLC. | ||
| busy | Interface Busy | Bool | OBSERVER | READONLY | Defines whether the PLC softdevice is busy. | ||
| hardwareErrorDescription | Hardware error description | String | OBSERVER | READONLY | Error Code description | ||
| hardwareErrorDescriptor | Hardware error descriptor | AError | UInt32 | OBSERVER | READONLY | This word encodes in bits describing the hardware error | |
| hardwareStatusBitField | Hardware state (hex) | AState | UInt32 | OBSERVER | READONLY | This word encodes in bits the hardware-status information of this device | |
| interlockOk | Interlock Ok | Bool | OBSERVER | READONLY | Defines whether interlock is ok (true) or broken (false). | ||
| interlockOn | Interlock On | Bool | OBSERVER | READONLY | Defines whether interlock surveillance is on or off. | ||
| interlockReadOnly | Interlock Read Only | Bool | USER | INITONLY | Defines whether interlock conditions are configurable from this interface. | ||
| triggers.trigX.enable | Enable | Bool | USER | RECONFIGURABLE | Enable/disable scheduled push for the specified property. | ||
| triggers.trigX.interval | Interval | Double | USER | RECONFIGURABLE | Push interval in milliseconds. Minimum 100 ms (TrainId Frequency) maximum 3e5 ms (5 minutes PLC limit). | ||
| triggers.trigX.property | Property | String | USER | RECONFIGURABLE | Alias name of the property to push. | ||
| epsilon | Epsilon | AEpsilon | Float | EXPERT | RECONFIGURABLE | The epsilon determines the amount of change until a new physical value is posted from the hardware | |
| hardwareRegion | Hardware Region | String | EXPERT | READONLY | The current region of the hardware decoded | ||
| hardwareState | Hardware state | String | EXPERT | READONLY | The current state of the hardware decoded | ||
| maxUpdateFrequency | Maximum Update Frequency | AMaxUpdFrq | Float | EXPERT | RECONFIGURABLE | set to limit maximum update frequency for some values. | |
| pollInterval | Poll interval | Float | EXPERT | RECONFIGURABLE | Hardware poll interval in seconds | ||
| propertiesToPoll | Properties to poll | VectorString | EXPERT | RECONFIGURABLE | All specified properties will be polled from the PLC with the given poll-rate | ||
| propertiesToRead | Properties to read | VectorString | EXPERT | RECONFIGURABLE | The specified properties will be read from the PLC by activating the Read button | ||
| softDeviceId | Soft device id | UInt32 | EXPERT | READONLY | |||
| waitingFor | Waiting For Command Reply | String | EXPERT | READONLY | Any call to the PLC will be published here, once the reply is received this property will be cleared. Commands will not be sent to the PLC until this property is cleared. | ||
| force | Force | AForce | Bool | ADMIN | RECONFIGURABLE | ??? | |
| functionBlockName | PLC Function Block Type | AFWBlock | String | ADMIN | READONLY | The type of the firmware block. | |
| fwInstanceName | PLC Instance name | AName | String | ADMIN | READONLY | The name of the firmware block instance. | |
| fwVersion | Framework Version | APlcFramworkVersion | String | ADMIN | READONLY | The version of the PLC framework. | |
| isInterlockOverridden | Interlocked Slots Enabled | Bool | ADMIN | READONLY | |||
| terminal | Terminal | ATerminal | UInt32 | ADMIN | READONLY | ??? |