Intelligent Technologies (
IT.
) D77B-DSNAP
Pub. No. MN05004001E
19
September 2002
Typical Application
The following figure illustrates a typical D77B-DSNAP application, where a single D77B-
DSNAP is connected to a single motor controller and where the motor controllers are
distributed throughout the DeviceNet subnet. The subnet is then being controlled by a PC or
PLC, which scans the D77B-DSNAP for control and monitoring information.
Figure 12: Typical D77B-DSNAP Application
Note: Such an application typically has more devices on DeviceNet than are shown in this
illustration, such as drives, I/O and user interface units.
Features
Table 19: Standard Protective Features
Note: The threshold values for Thermal Overload and Phase Current Unbalance can not be
modified.
DeviceNet
System
Controller
Trip
Definition
Phase Current
Unbalance/Phase
Loss
A phase current unbalance trip will occur if one or two of the line currents are 40 –
60% or less of the remaining line(s) for longer than 10 seconds.
A phase loss trip will occur with a load current of at least 75% of the minimum FLA
if one of the two input line voltages is lost, with the line current going to zero for
longer than 10 seconds.
Thermal
Overload
While the motor is running and depending on the FLA and trip class settings, when
the FLA is exceeded for a period of time (depending on the trip class setting), a
thermal overload trip will occur. For more information on this feature, see the
Contactor and Starter User Manual (Publication No. 49400).