The lighting business is changing, and in many ways,
becoming more complicated and confusing
This month we discuss AC vs. DC power, 12 vs. 24 volts, and dimming LEDs
All LEDs operate using low voltage DC power, but line
voltage AC is how we deliver electricity from the power plant
to our homes. We first have to convert line voltage to low
voltage and then convert AC to DC.
Transformer
Converts line
voltage to low
voltage
Rectifier
Convert from
AC to DC
AC is converted to DC in a remote power supply.
120 Volt
DC LED Strip
SS2C Soft Strip
24V DC LED
TEB-75L-24DC
or
AC is converted to DC right on board the fixture.
AC LED Strip
Audrey Vanity
24V AC LED
What is the difference between 12 and 24 volts?
Low voltage means anything under 30 volts, regardless of whether it is AC or DC. 12 volt systems work
for smaller LED Soft Strip runs less than 25 feet. If we have a larger system (i.e. cove lighting
application), we’d use 24 volts. 24 volts allows us to create LED Soft Strip runs up to 40 feet with less
voltage drop and still use the same 14 gauge wire.
Low voltage lighting for landscape and swimming pool lighting must be under 15 volts.
VS
12 Volt
24 Volt
What dimmer should I use?
Dimming hardware varies depending on the type of power supply used. The TEB-60L-12DC or
TEB-75W-24DC (electronic power supplies), best for fitting discreetly under cabinets, use ELV dimmers*;
with a minimum load of 30 watts. 0-10V power supplies have no minimum load issues and easily integrate
into home automation systems. 0-10V systems often have smoother dimming but require two additional
wires as well as larger power supplies.
*Always verify that the power supply, LED product and dimmer are cross referenced on the manufacturer’s literature to ensure
compatibility.
Typical ELV Dimming System
TEB-60L-12DC or
TEB-75L-24DC
G
N
L
GRAY
PURPLE
LED -
BROWN
LED +
RED
GND
0-10V
Dimming
L N G
Typical 0-10V Dimming System
PSB-96W-010-24VDC
ELV Dimming
VS
0-10V Dimming
10”x6”x3”
7.75”x2.5”x1.5”
TEB-60L-12DC or
TEB-75L-24DC
PSB-96W-010-24VDC