Emerson E2 User Manual

The chart below describes symptoms and solutions if troubleshooting the system or equipment is needed. For further 

information, contact Emerson Retail Solutions Service at 1-800-829-2724. 

I/O Network Problems

I/O board not getting power.

Check I/O board power--is the 
green STATUS light on? If not, 
check power wiring connections, 
and use a multimeter to verify 
the board is getting 24VAC.
Reset power to board.

I/O board not communicating or 
won’t come online.

Check I/O network connections:
1. Check wire polarity (positive 
to positive/negative to negative)
2. Check for broken or loose 
wires.

Dip switches are set incorrectly.

Check I/O board network dip 
switches. Verify network ID 
number is not a duplicate and 
that baud rate switches are set to 
9600. (If switches are wrong, 
make changes and then reset the 
controller.) Refer to Section 
6.1.6, Network ID Numbers 
(Board Numbers).

Terminating resistance jumpers 
are set incorrectly.

Check for proper setting of ter-
minating resistance jumpers. 
Network segment should be ter-
minated on the two endpoints of 
the daisy chain and unterminated 
everywhere else. Refer to Sec-
tion 6.1.8, Setting the Terminat-
ing and Biasing Jumpers.

Boards are not powered.

Check Network/Power voltages. 
Refer to Section 6.1.9, Powering 
the I/O Boards.