Process image of the cam controller

Input process image

Via the input process image the PLC can influence the function of the cam controller at runtime. On the PLC side these variables are declared as outputs and linked with the input process image of the cam controller in the System Manager.

• ToolSafe: not implemented
• ReverseMode: The cam controller manages two cam tables (standard and reverse). For each cam the table in which it becomes active can be parameterised. Via the variable ReverseMode the PLC can specify which of the two cam tables is used.
• Coupled: The Coupled signal must be set to TRUE by the PLC in order to activate the monitoring functions of the cam controller. It indicates that the encoder is mechanically coupled and that the monitoring functions are therefore active.
  The calculation of Actual HPM starts as soon as Coupled is set to TRUE. Actual HPM will be initialised with HPM Preset while Coupled is set to FALSE.
• HPM Preset: Set speed value at constant encoder speed after start-up. This value is mainly required for calculating the time cams and must be set by the PLC before start-up.
  The unit of HPM Preset is [1/min] if the Use Encoder precisionencoder parameter is set to FALSE. When high precision is enabled, the unit changes to [1/1000 min]
• HPM Difference: Maximum speed deviation [rpm] from the set value HPM Preset. A deviation leads to recalculation of the cam table. A value of 0 avoids any automatic recalculation of cams.
• Reset I/O Errors: Via this variable the PLC can reset an I/O error indicated by the cam controller. To this end a value of 1 is written to the variable and reset to 0 during the next cycle.
• Reset Encoder Error: Via this variable the PLC can reset an encoder error indicated by the cam controller. To this end a value of 1 is written to the variable and reset to 0 during the next cycle.
• Reset Shaft Error: Via this variable the PLC can reset a shaft failure (Shaft Error) indicated by the cam controller. To this end a value of 1 is written to the variable and reset to 0 during the next cycle.
• Reset HPM Error: Via this variable the PLC can reset an HPM error indicated by the cam controller. To this end a value of 1 is written to the variable and reset to 0 during the next cycle.
• Enable Counters: Via bits 0..4 of the data word one of the five counters is activated (see output process image).
• Preset Counter 1: Initial value for counter 1.
• Preset Counter 2: Initial value for counter 2.
• Preset Counter 3: Initial value for counter 3.
• Preset Counter 4: Initial value for counter 4.
• Preset Counter 5: Initial value for counter 5.
• Max val counter 1: Maximum value for counter 1. After this value the counter changes to 0.
• Max val counter 2: Maximum value for counter 2. After this value the counter changes to 0.
• Max val counter 3: Maximum value for counter 3. After this value the counter changes to 0.
• Max val counter 4: Maximum value for counter 4. After this value the counter changes to 0.
• Max val counter 5: Maximum value for counter 5. After this value the counter changes to 0.
• Brake Enabled: Brake enable. The data word is resolved into 32 individual variables for the first 32 output tracks. The variables activate brake enable for output tracks 0 to 31. Brake enable is used in conjunction with brake cams.
  If more than 32 outputs were configured, additional data words (Brake Enabled 1..9) are used.
• PLC AND Mask: Via the AND mask the PLC can deactivate individual output tracks. A track can only become active, if the associated bit (0..31) has the value 1, otherwise the output is permanently inactive.
  The output tracks can be activated through a PLC program, once the cam encoder has reached its constant speed (HPMpreset). During the start-up or braking phase the PLC program should set the mask to 0, thereby deactivating the output tracks.
  The AND mask has priority over the OR mask. If more than 32 outputs were configured, additional data words (PLC AND Mask 1..9) are used.
• PLC OR Mask: Via the OR mask the PLC can explicitly activate individual output tracks. A track becomes permanently active, if the associated bit (0..31) has the value 1.
  The AND mask has priority over the OR mask. If more than 32 outputs were configured, additional data words (PLC OR Mask 1..9) are used.

Output process image

• Actual HPM: Current speed of the cam encoder.
  The unit of Actual HPM is [1/min] if the Use Encoder precisionencoder parameter is set to FALSE. When high precision is enabled, the unit changes to [1/1000 min]
  The calculation of Actual HPM starts as soon as Coupled is set to TRUE. Actual HPM will be initialised with HPM Preset while Coupled is set to FALSE.
• Cams in use: not implemented
• I/O Errors: This variable is set if the cam controller detects an I/O error.
• Encoder Error: This variable is set if the cam controller detects an encoder count error. (The encoder value does not change)
• HPM Error: This variable is set if the cam controller detects an encoder speed deviation.
• Timeout Rec. 1: Only for special configuration with dedicated Lightbus I/O card. In this case a diagnostic value relating to the card is indicated.
• Timeout Rec. 2: Only for special configuration with dedicated Lightbus I/O card. In this case a diagnostic value relating to the card is indicated.
• Counter 1: Count of counter 1. The value is initialised with an initial value specified by the PLC and incremented with each encoder revolution as long as the associated bit of the Enable Counters variable in the input process image is 1.
• Counter 2: Count of counter 2.
• Counter 3: Count of counter 3.
• Counter 4: Count of counter 4.
• Counter 5: Count of counter 5.
• Counter ready: The data word is broken down into individual bits. Bits 0 to 4 indicate that the maximum value for counter 1 to 5 was reached.
• Cam Inputs: Only for special configuration with dedicated Lightbus I/O card. In this case the digital inputs of the connected digital I/O box are indicated here.
• Cam Output: Current status of the output tracks. The data word is broken down into 32 individual bits that can be linked with the connected digital outputs.
  If more than 32 outputs were configured, additional data words (Cam Output 1..9) are used.