When the TDA Module is the last device on the bus, make sure the end-of-line (EOL) switch on the circuit board is in the On position. This requires the cover of the device to be removed; therefore, the last device should be determined and the EOL switch set to the proper position before applying the tamper evident label to the enclosure cover.
Each module has an EOL switch, which, when set to ON, sets the module as a terminating device on the bus. See Figure 1 for the EOL switch location. The default EOL switch position is Off (Figure 2).
Figure 1. TE-74 Module with Cover Removed Showing EOL Switch Location
Figure 2. End-of-Line Switch Positions
