Wire Length

[lautend]

I've heard the maximum wire length for 12 gauge cable is 200 ft with the transformer I'm using. Does that mean for each lead, if there are multiple leads, or is that a total that all wire in total must stay below?

Dave

[sitelights]

The simple answer is that the mythical 200' is per run not in total.

Wire length is only one aspect of low voltage lighting performance. In order to achieve a technically correct system i.e. with all lamps getting 10.8 to 12.0v it is necessary to design the system using the shortest possible main cable lengths. The factors that determine acceptable performance are: transformer regulation, cable gauge, lamp load and cable length. While it is possible to use a 200' run of 12/2 the lamp load would have to be minimal since if you start with 12v output at the transformer loss through resistance of the cable would limit the lamp load to less than 50w to achieve the 10.8v target at 200'. It is impractical to attempt to run 200' of 12/2 to power one or two lamps. The many variables preclude a simple answer. A more precise answer would require the following information: Does the transformer have more than one output voltage (HI-LO switch or 13v or 14v outputs) and what is the planned lamp load, wire size and length of each wire run? There are a number of posts that address this problem. The "search" function will take you to the relevant posts if you key in "voltage drop", "transformer regulation" or scan the posts under the appropriate headings on the home page to access the technical info.

If you provide information on all the parameters outlined above it would be possible to assist you in the technical design.