Woodward Discrete Output for Driver Status Indication

Shutdown/Reset Discrete Input

When the shutdown contact is opened, the driver goes into a shutdown mode

and the valves are commanded to and held at minimum position. When the

shutdown contact is closed, the driver returns to ‘run’ mode and it resets all driver

faults.

Discrete Output for Driver Status Indication

The discrete output contact is normally on/closed (customer-supplied power

applied to load such as a trip-string relay) under normal driver operation, and

turns off/opens to indicate any detected shutdown condition within the driver.

Both alarm and shutdown indications are latching, which means a reset

command is required to clear the fault. The Service Tool program can be used to

interrogate the cause of the alarm or shutdown. The CAN communications can

also be used to determine alarm and shutdown causes.

The Swift Gas Metering System will continue to operate with an alarm condition

(for example, failure of the primary demand signal). However, the unit will cease

to operate on a shutdown condition (for example, failure of position demand input

signal).

RS-232 Communications Port

An RS-232 communications service port is provided in the J1 harness plug for

connection to a PC service tool. This connection is a typical three-wire RS-232

communication (Tx = J1-A1. Rx = J1-A2. Gnd = J1-A3), which is limited to 15 m

(50 feet). The port supports OPC protocol and has fixed communications settings

of 38.42 K baud rate, 8 data bits, no parity, and 1 stop bit. Refer to Chapter 7 for

details on the Service Tool.

CAN Communications Port

The driver has CAN communications, version 2.0B, with 29-bit identifiers. The

CAN port supports independent positioning (position demand from CAN) and

shutdown of each driver channel. It also supports driver diagnostic monitoring

and position demand feedback. Reading of CAN parameters is available

regardless of the configured Demand Source. The address and data rate

parameters are set using the Service Tool. The data rate may be chosen from

125 kbps, 250 kbps, and 500 kbps.