Watlow Series SD6 PID Controller with DeviceNet Addendum - Manual (Page 8)

Wa t l o w S e r i e s S D 6 P I D w i t h D e v i c e N e t ■ 8 ■
Class Services: NONE
Instance Services:
• 0x0E GET ATTRIBUTE SINGLE
• 0x10 SET ATTRIBUTE SINGLE
Additional Poll Connection information:
• In the event of the input error, a valid process value reading is no longer available. The poll connection will return a
value of 9999.999 for the process value while the error condition exists.
• Bit 1 and bit 2 of byte 4 in the output poll connection select whether set point and auto / manual mode values are
changed from the SD’s front panel or else over DeviceNet through the poll connection. Setting the bit to “zero” will relin-
quish control of the parameter to the DeviceNet master device (typically the master is a PLC). Setting the bit to “one” will
retain control of the parameter locally at the front panel of the Series SD controller. If there is a loss of communications,
control of auto / manual mode and adjustment of set point will automatically return to the Series SD front panel regardless
of the settings of byte 4 in the output poll connection.
Connection Object
Class Code: 05hex
The Connection Class allocates and manages the internal resources associated with both I/O and Explicit Messaging
Connections. The specific instance generated by the Connection Class is referred to as a Connection Instance or a
Connection Object.
A Connection Object within a particular module actually represents one of the end-points of a Connection. It is possible for
one of the Connection end-points to be configured and “active” (e.g., transmitting) without the other end-point(s) being
present. Connection Objects are used to model the communication specific characteristics of a particular application-to-
application relationship. A specific Connection Object Instance manages the communication-specific aspects related to an
end-point.