6
2
3
4
5
6
1
Bottom Ports Purpose
1. Station output ports  
(15-pin connectors) (up to four) 
These connect to the circuit boards in the Sentinel satellite, controlling up to  
12-stations each for a maximum of  48 stations.
2. AC adapter and the red “power on” light LED ashes if  a program is running.  
The slower the ash, the slower the code is running
3. USB port Allows connecting a thumb drive for “ashing” of  the rmware.
4. 2-prong port 24 VAC connection
5. Serial Port 1 (9-pin connector) Both top and bottom serial ports support communications devices, standard off  the shelf  
serial cables, and are optically isolated.
6. Two fuse sockets with a red LED light next 
to each fuse socket
When the red LED is lit, indicates a blown fuse.