Bard MEGA-TEC W090A, Service Instructions Manual

Page: 55 / 159

Manual 2100-671C
Page 53 of 59
Modbus Troubleshooting for MEGA-TEC
Use the following instructions if alarm 96, 97, 99, 101
or 103 occurs.
1. Disconnect the communication wires from the
condenser fan (Figure 60) and unplug the ModBus
from the expansion module (C.PCOe) as shown in
Figure 61. Verify that the other end of the ModBus
is plugged into the upper field bus connection
(FieldBus 1) on the PLC board (see Figure 62).
FIGURE 60
Disconnect Condenser Fan Communication Wires
FIGURE 61
Unplug Modbus from Expansion Module
FIGURE 62
Verify Modbus is Connected to PLC Board
2. Using the TEC-EYE, check to see if the blower
motor is online.
FIGURE 63
Verify Blower Motor Is Online
A. Yes. Proceed to Step 3.
B. No. Reverse the polarity of the wires coming
from the blower motor at the terminal block
(terminals 14 and 18, see Figure 64).
FIGURE 64
Reverse Polarity of Wires from Blower Motor