GE LM10, Motor Protection System A.2.8 Explicit Messaging, Monitoring Data, Description

CHAPTER A: LM10 AND GE FANUC 90-30 WITH DEVICENET™

ZDouble-click the added slave device to view the data area for Connection 2.

ZOpen the Reference View Table and add address %I00089.

ZTo interpret the 1 byte of status information for address %I00097, refer to Object Class 4, Instance 54 in Assembly Object on page 5– 48.

A.2.8 Explicit Messaging

Description:

Explicit messaging provides multi-purpose, point-to-point communication paths between two devices. It typically provides request/response-oriented network communication used to perform node configuration and problem diagnosis.

In the GE Multilin LM10 Motor Protection System. explicit messaging is used for configuration and monitoring.

Use the following procedure to set the network for explicit messaging:

ZFor the master side: In the Network Setting > DN9030 Master Properties menu, disable connections 1 and 2 by selecting Enable Explicit Connection.

ZSet the Message Request Size and Message Response Size to 20 bytes.

ZFor the slave side: In the Network Setting > Disable Connection 1 & 2 window, select Explicit Message Size set the value as 20 bytes.

ZConnect the PLC and download the hardware logic. The configuration should be shown as = EQ.

ZObserve the DeviceNet master module LEDs.

All three LEDs for NET POWER, MOD STATUS, and NET STATUS should turn solid green. Refer to LEDs on page 3–19to interpret the device LED status.

Explicit messaging between the DeviceNet master module and LM10 slave takes place using COMMREQ ladder instructions.

A communication request begins when a COMMREQ ladder instruction is activated in the PLC application program. The CPU sends the COMMREQ to the DeviceNet™ master module in the PLC system. The module receives the command and performs the requested function.

Monitoring Data:

The ladder logic for monitoring data from the GE LM10 Motor Protection System using COMMREQ is shown in Ladder Logic for Data Monitoring on page A–13.The ladder logic is configured as follows:

•Rung 1 and 2 have a timer (thousands), as well as set and reset coils, which toggle the T1 contact after the timer PV value overflows. With the values shown, the T1 contact will toggle every five (5) seconds.

LM10 MOTOR PROTECTION SYSTEM – INSTRUCTION MANUAL A–11