Watchdog v2

A combined network watchdog and network driver with facilities for propagating faults from the function block engine, Ethernet, or device comms.

Suitable for pair and ring topologies. Use in conjunction with Watchdog v1 function blocks for branch or star topologies.

To reset a pair or ring following a fault that is propagated, disable the Propagate to Network parameter in one device until the Status parameter returns to OK.

• Available only in the dw2xx & dw2xx-v2 series products
• Requires library: System & I/O
• Singleton function block
• Firmware versions 0x201F and later

Watchdog v2 - Network Input

Make a drive.web-over-Ethernet connection here from a Network Driver in another drive.web device.

If the connection fails to write a non-zero number here, the timer begins to count down.

Watchdog v2 - Timer

Shows the current time of the watchdog countdown.

Fault is active (low) if the timer counts down to zero.

Watchdog v2 - Initial Holdoff

Inhibits the watchdog countdown for the specified period, following device power-up.

Watchdog v2 - Timeout

The time, following an absence of network updates at Network Input, before the fault occurs.

Watchdog v2 - Fault Output

Active low. Active when a fault occurs at Network Input or Fault Input.

Also active when a general Ethernet failure occurs, unless Fault on Ethernet Down is disabled.

Also active when a device comms failure occurs in drive-dedicated devices, unless Fault on Device Comms Fail is disabled.

Watchdog v2 - Network Driver

Connect directly to Network Input parameter(s) in other device(s) using drive.web-over-Ethernet connection(s).

Alternates between a raw value of one or two at every function block execution cycle, unless Fault Output is active (low).

Equals zero when a fault is active.

Watchdog v2 - PLX Driver

Only present for PLX Digital DC Drive devices. Connect to PLX PIN787, driveWeb Watchdog Timer.

If the connection fails to write a number here, the parameter will count down and cause a drive alarm (trip if the drive is started).

Watchdog v2 - Fault Input

Active low. Use to propagate fault conditions from the drive.web device's function block engine.

Watchdog v2 - Propagate to Network

Enable to cause Network Driver to equal zero when Fault Output is active.

Watchdog v2 - Propagate to PLX

Enable to cause PLX Driver to equal zero when Fault Output is active.

Watchdog v2 - Fault on Ethernet Down

Enable to cause Fault Output to be active if the Ethernet Link fails.

Watchdog v2 - Fault on Device Comms Fail

Only present in drive-dedicated devices.

Enable to cause Fault Output to be active if the device comms fail.

Watchdog v2 - PLX Trip Time

When PLX Driver is connected to PIN787, driveWeb Watchdog Timer, a drive alarm will occur after this time, following a fault.

Watchdog v2 - Status

Indicates the current state of the function block.

Equals zero when OK

Enumerations are provided for various faults and states.