Grain Systems PNEG-1745 - Manual (Page 13)

3. Installation
PNEG-1745 WatchDog 13
5. Plug the DB9 connector of Serial Cable #1 into the DB9 connector on the WatchDog circuit board.
Tighten the two (2) screws to secure the connection. (See Figure 3F.)
Figure 3F
6. If a cellular modem is being used, the bare leads of the WatchDog power cable should be connected
to the cellular modem power terminals as follows:
Black with faint white line lead - PWR +
Black lead with faint white writing lead - PWR GND
Figure 3G
NOTE: These are the same slots holding the wires coming from the moisture control panel.
DB9 Connector