Bray 70 Series SERVO PRO DeviceNET - Manual (Page 15)

S70 DeviceNet Servo Installation & Maintenance Manual
2000 BRAY CONTROLS Page 14 of 24
controller has exclusive control of the S70 Servo via the polled message connection. The polled
message connection allows the process controller to position the S70 Actuator, and receive the
present actuator position. If the process controller establishes an additional Explicit message
connection, the process controller could also simultaneously monitor or control other features of
the S70 Servo as described in Section (3.1.6).
3.1.6 Supported Attributes
The S70 Servo supports attributes in the Assembly Class (4), Instance (1), which provide
access to the features that are also accessible in the EDS (Electronic Data Sheet). These
attributes are provided in the event the user wishes to monitor or control aspects of the S70
Servo beyond a polled message connection.
A process controller will typically access the S70 Servo through a polled message connection.
A polled message connection only sends and receives the S70 Servo actuator position. To
monitor or control additional features of the S70 Servo, an explicit message must be sent to the
S70 Servo with the appropriate attribute.
As an example, to monitor the temperature of the S70 Actuator motor, the process controller
would send the Group 2 Explicit message Assembly (4), Instance (1), and Attribute (101). The
response from the message would be the two-byte temperature.
The attributes supported by the S70 Servo are listed in Table 3. All attributes can be read (GET
service) and set (SET Service) unless otherwise noted. As an example, attribute 100, Valve
position, if “SET” would position the valve, if the attribute were read (GET), the present valve
position would be returned.
The EDS (Electronic Data Sheet) file, which is provided with the S70 Servo, contains the most
current information pertaining to attribute data. Use the EDS as a reference for data types, data
formats, and data conversion. Also check the Bray WEB site to obtain the latest EDS file for the
S70 Servo (www.bray.com).