mikejrc
Active Member
Nice EOLR explaination. This should help a lot of people understand End Of Line Resistors. We need more write ups like this.
I will state one other fact concerning EOLR's and lightning transients. Most security controls reference one side of their zone loop to the negative side of the power supply. Without the end of line resistor in the circuit, any lightning transients are quickly bled off to negative. With an end of line resistor installed, there is more of the lightning transient having to be bled off through the transient protection network located on the control panel. You will have more chance of lightning damage with the EOLR installed rather than the zone loop connected directly to negative.
If you are not wiring the EOLR at the end of the zone loop and the control allows for programming the EOLR to a normally closed zone loop, remove the EOLR from the circuit for better lightning transient protection.
is there a way to have the EOLR installed and have better transient protection at the same time? Could you elaborate on the Elk's internal transient network?