I see that the forum members here seem to take pleasure in complicated voltage calculations. I'm preparing an article on voltage losses associated with all the common wiring methods used in landscape lighting. If anyone here wants to take on the following wholly or in part, please do. Or, if you know of a source, please pass that on.
I'm interested in calculating the voltage at light fixtures in a 12V AC lighting system for four different wiring methods.
I'm clear about the CAST Spider splice method and associated voltage loss calculations. This method uses a homerun wire connected to a splice hub. From this hub, a number of fixtures are connected with equal length lead wires.
There are four other common wiring methods that I'd like to get the voltage loss calculations clear on:
1. Daisy chain method (all fixtures connected in a chain - a single wire is run passing near all fixture locations, each fixture is then spliced onto this wire, wire ends at last fixture).
2. Daisy chain method with loop (same as above, except a wire is run connecting the splice point for the first fixture and the splice point of the last fixture).
3. Loop method (same as the above method except that the additional wire connects the last fixture to transformer common and voltage tap).
4. T-method (same as the daisy chain except the homerun wire connects with the daisy chained fixtures at the center fixture instead of at the end).
I'm looking for the voltage at each fixture.
The following terms can be used:
V=voltage; VT=voltage at the transfomer tap; VFx=voltage at fixture number "x"; L=wire length; WFx=lamp wattage at fixture "x"; Wtot=total lamp wattage of system; R=wire resistance value
Have fun and thanks!
I'm interested in calculating the voltage at light fixtures in a 12V AC lighting system for four different wiring methods.
I'm clear about the CAST Spider splice method and associated voltage loss calculations. This method uses a homerun wire connected to a splice hub. From this hub, a number of fixtures are connected with equal length lead wires.
There are four other common wiring methods that I'd like to get the voltage loss calculations clear on:
1. Daisy chain method (all fixtures connected in a chain - a single wire is run passing near all fixture locations, each fixture is then spliced onto this wire, wire ends at last fixture).
2. Daisy chain method with loop (same as above, except a wire is run connecting the splice point for the first fixture and the splice point of the last fixture).
3. Loop method (same as the above method except that the additional wire connects the last fixture to transformer common and voltage tap).
4. T-method (same as the daisy chain except the homerun wire connects with the daisy chained fixtures at the center fixture instead of at the end).
I'm looking for the voltage at each fixture.
The following terms can be used:
V=voltage; VT=voltage at the transfomer tap; VFx=voltage at fixture number "x"; L=wire length; WFx=lamp wattage at fixture "x"; Wtot=total lamp wattage of system; R=wire resistance value
Have fun and thanks!
