This function block gives the user a detailed summary of the status of one (or both) of the encoder(s). Included in the encoder status are:

• Communication Status
• Direction Indicator
• Separate Channel A & B Status (Z on appropriate options)
• Separate Channel A & B Alarms (Z on appropriate options)

• Available only in the dw2xx series products
• Requires library: System & I/O
• Requires: Single or Dual Encoder
• Singleton function block
• Firmware versions 0x2015 and later

This parameter reflects the status of the communication channel to either the internal encoder (dwOption -15) or to an External Encoder Module (dwOptions -40 through -46).

For normal operation, the ENC1 Comms State must indicate an OK state. If communications is lost for at least 20 milliseconds, a Fault is indicated. If the problem persists check for voltage variations on the module's power supply and the I2I Encoder Interface Port cabling.

Indicates the current status of DIN1 (Terminal E4). The transition level is 8.2 Vdc (+/-7%).

Indicates the current status of the input channel.

• Low: A < -A by more than 2 Vdc.
• High: A > -A by more than 2 Vdc.

Indicates the current status of the input channel.

• Low: B < -B by more than 2 Vdc.
• High: B > -B by more than 2 Vdc.

Indicates the current status of the input channel.

• Low: Z < -Z by more than 2 Vdc.
• High: Z > -Z by more than 2 Vdc.

This parameter indicates the relationship of encoder channel A with respect to encoder channel B. To change the indication for a particular direction of rotation, swap A and -A on the input terminals.

For proper operation, this parameter must read OK and indicates the presence of the input channel and its complement. If an Alarm state is indicated, the associated function blocks will behave as follows:

• ENC# Speed type function blocks will reset to a zero output.
  
  
• ENC# Cyclic Position and ENC# Linear Position type function blocks will hold their Internal Count.

These actions are considered the safest behavior for the associated application; however, as you may expect, the system's performance will suffer during the Alarm state. For critical applications, a drive.web connection may be made from this parameter to any alarm handling logic designed by the user.

If the alarm clears, the Status will immediately return to OK (i.e., alarm conditions are not latched).

Possible causes for an Alarm state are shown below:

• Short circuit between input channels.
  
  
• Open circuit on the input channels.
  
• Low Input Differential Voltage
  
  -10 V < Common Mode Voltage < 13.2 V

  

  | Differential Voltage | < 275 to 475 mV
  

  The CH2 signal going high results in the Status parameter changing to a faulted condition.

• Outside Common-Mode Voltage Range
  
  Common Mode Voltage < -10 V or 13.2 V < Common Mode Voltage
  

  

  The CH3 signal going high results in the Status parameter changing to a faulted condition.

For proper operation, this parameter must read OK and indicates the presence of the input channel and its complement. If an Alarm state is indicated, the associated function blocks will behave as follows:

• ENC# Speed type function blocks will reset to a zero output.
  
  
• ENC# Cyclic Position and ENC# Linear Position type function blocks will hold their Internal Count.

These actions are considered the safest behavior for the associated application; however, as you may expect, the system's performance will suffer during the Alarm state. For critical applications, a drive.web connection may be made from this parameter to any alarm handling logic designed by the user.

If the alarm clears, the Status will immediately return to OK (i.e., alarm conditions are not latched).

Possible causes for an Alarm state are shown below:

• Short circuit between input channels.
  
  
• Open circuit on the input channels.
  
• Low Input Differential Voltage
  
  -10 V < Common Mode Voltage < 13.2 V

  

  | Differential Voltage | < 275 to 475 mV
  

  The CH2 signal going high results in the Status parameter changing to a faulted condition.

• Outside Common-Mode Voltage Range
  
  Common Mode Voltage < -10 V or 13.2 V < Common Mode Voltage
  

  

  The CH3 signal going high results in the Status parameter changing to a faulted condition.

If the Z channel is used, this parameter must read OK indicating the presence of the input channel and its complement. If desired, this parameter may connected to user logic so the appropriate action may be taken when an Alarm state is indicated. When the alarm clears, the Status will immediately return to an OK state (i.e., alarm conditions are not latched).

Possible causes for an Alarm state are shown below:

• Short circuit between input channels.
  
  
• Open circuit on the input channels.
  
• Low Input Differential Voltage
  
  -10 V < Common Mode Voltage < 13.2 V

  

  | Differential Voltage | < 275 to 475 mV
  

  The CH2 signal going high results in the Status parameter changing to a faulted condition.

• Outside Common-Mode Voltage Range
  
  Common Mode Voltage < -10 V or 13.2 V < Common Mode Voltage
  

  

  The CH3 signal going high results in the Status parameter changing to a faulted condition.

This parameter reflects the status of the communication channel to either the internal encoder (dwOption -15) or to an External Encoder Module (dwOptions -40 through -46).

For normal operation, the ENC2 Comms State must indicate an OK state. If communications is lost for at least 20 milliseconds, a Fault is indicated. If the problem persists check for voltage variations on the module's power supply and the I2I Encoder Interface Port cabling.

Indicates the current status of DIN2 (Terminal E5). The transition level is 8.2 Vdc (+/-7%).

Indicates the current status of the input channel.

• Low: A < -A by more than 2 Vdc.
• High: A > -A by more than 2 Vdc

Indicates the current status of the input channel.

• Low: B < -B by more than 2 Vdc.
• High: B > -B by more than 2 Vdc.

Indicates the current status of the input channel.

• Low: Z < -Z by more than 2 Vdc.
• High: Z > -Z by more than 2 Vdc.

This parameter indicates the relationship of encoder channel A with respect to encoder channel B. To change the indication for a particular direction of rotation, swap A and -A on the input terminals.

For proper operation, this parameter must read OK and indicates the presence of the input channel and its complement. If an Alarm state is indicated, the associated function blocks will behave as follows:

• ENC# Speed type function blocks will reset to a zero output.
  
  
• ENC# Cyclic Position and ENC# Linear Position type function blocks will hold their Internal Count.

These actions are considered the safest behavior for the associated application;however, as you may expect, the system's performance will suffer during the Alarm state. For critical applications, a drive.web connection may be made from this parameter to any alarm handling logic designed by the user.

If the alarm clears, the Status will immediately return to OK (i.e., alarm conditions are not latched).

Possible causes for an Alarm state are shown below:

• Short circuit between input channels.
  
  
  
• Open circuit on the input channels.
  
  
• Low Input Differential Voltage
  
  -10 V < Common Mode Voltage < 13.2 V

  

  | Differential Voltage | < 275 to 475 mV
  

  The CH2 signal going high results in the Status parameter changing to a faulted condition.

• Outside Common-Mode Voltage Range
  
  Common Mode Voltage < -10 V or 13.2 V < Common Mode Voltage
  

  

  The CH3 signal going high results in the Status parameter changing to a faulted condition.

For proper operation, this parameter must read OK and indicates the presence of the input channel and its complement. If an Alarm state is indicated, the associated function blocks will behave as follows:

• ENC# Speed type function blocks will reset to a zero output.
  
  
• ENC# Cyclic Position and ENC# Linear Position type function blocks will hold their Internal Count.

These actions are considered the safest behavior for the associated application; however, as you may expect, the system's performance will suffer during the Alarm state. For critical applications, a drive.web connection may be made from this parameter to any alarm handling logic designed by the user.

If the alarm clears, the Status will immediately return to OK (i.e., alarm conditions are not latched).

Possible causes for an Alarm state are shown below:

• Short circuit between input channels.
  
  
  
• Open circuit on the input channels.
  
  
• Low Input Differential Voltage
  
  -10 V < Common Mode Voltage < 13.2 V

  

  | Differential Voltage | < 275 to 475 mV
  

  The CH2 signal going high results in the Status parameter changing to a faulted condition.

• Outside Common-Mode Voltage Range
  
  Common Mode Voltage < -10 V or 13.2 V < Common Mode Voltage
  

  

  The CH3 signal going high results in the Status parameter changing to a faulted condition.

If the Z channel is used, this parameter must read OK indicating the presence of the input channel and its complement. If desired, this parameter may connected to user logic so the appropriate action may be taken when an Alarm state is indicated. When the alarm clears, the Status will immediately return to an OK state (i.e., alarm conditions are not latched).

Possible causes for an Alarm state are shown below:

• Short circuit between input channels.
  
  
  
• Open circuit on the input channels.
  
  
• Low Input Differential Voltage
  
  -10 V < Common Mode Voltage < 13.2 V

  

  | Differential Voltage | < 275 to 475 mV
  

  The CH2 signal going high results in the Status parameter changing to a faulted condition.

• Outside Common-Mode Voltage Range
  
  Common Mode Voltage < -10 V or13.2 V < Common Mode Voltage
  

  

  The CH3 signal going high results in the Status parameter changing to a faulted condition.

This parameter keeps a tally of total errors on the communication link effectively recording every transition of the ENC1 Comms State and ENC2 Comms State.