To determine the correct wire gauge to use on “one circuit” the following information is required: 1. The quantity, voltage and current draw of all lock(s) to be used. 2. The distance in feet from the power supply to the furthest lock. Add together the current draw (amps) of all locks on the same circuit. Cross reference the total amps with the distance between the power supply and the farthest lock to determine the wire gauge required. “One circuit” implies that two wires are being run from the power supply to one or more locks in parallel. The last lock on the pair of wires should not exceed the maximum distance number shown on the chart for that gauge of wire and total current draw in Amps. If the wire gauge size or maximum distance is inadequate for your application, divide the quantity of locks on that circuit to create two or more separate circuits and use the chart to figure each new circuit independently. This will increase the total number of wires being run but it will allow for a smaller gauge of wire to be used and it will increase the maximum distance from the power supply to the furthest lock on that circuit even though the same power supply is being used. The chart shows the maximum distance allowable for a 5% voltage drop from the power supply to the furthest lock on one circuit. All wiring must be installed in accordance with all state and local codes.