In figure 9 Dave shows what can happen. The detection device is triggered but there is NO ALARM because the end of line resistor is in the wrong place! Compare figures 8 and 9 with the correctly installed figure 4, shown again for comparison.
When the end of line resistor is incorrectly installed in the control panel, the security system will work correctly MOST of the time but not ALL of the time. A short in the wires can cause the system to work improperly. The correct placement of the end of line resistor is critical for proper supervision of the circuit.
Now that you know what to look for, go to Pictures 1 to see just a few of the many improperly installed security systems in the Colorado Springs, Colorado area.
Let Dave do it right the first time!