Lutron Electronics MAELV-600-LA Manual

FOR YOUR INFORMATION ...
Guide to Dimming Low-Voltage Lighting
Overview
This guide answers typical questions encountered by
Lutron's Technical Assistance and Applications
personnel concerning low-voltage dimming applications.
Lutron manufactures low-voltage dimmers for low-
voltage fixtures that use magnetic transformers.
To control electronic (solid-state) transformer-supplied
low-voltage lighting, Lutron developed special dimming
circuitry after an extensive engineering research and
development program. This technology has been built
into a series of dimmers specifically for ELV transformer
loads.
Lutron offers dimmers for both load types in a variety of
product families.
Facts About Low-Voltage Lighting
Why Use Low-Voltage Lighting?
• Low-voltage lighting provides an excellent source of
illumination when a precise, concentrated beam of
light is required.
• Low-voltages contribute to extended lamp life and
increased safety.
• Small fixture sizes permit lamps to be easily aimed
and reconfigured.
• Common applications include residences, display
lighting, task lighting, and product highlighting.
What is Low-Voltage Lighting?
Low-voltage lighting uses a transformer to reduce a
120VAC line voltage to 12VAC or 24VAC. This lower
voltage is then used to power an incandescent low-
voltage lamp. Examples of low-voltage lamps are
AR111, MR16, MR11, PAR36, T3-1/4, T5, striplites, etc.
Many, but not all low-voltage lamps are tungsten
halogen.
Where is the Transformer Located?
A low-voltage transformer may be mounted remotely or
as an integral part of the fixture.
Does Dimming Affect Lamp Life?
Dimming will increase the life expectancy of low-voltage
lamps. Occasionally, darkening of a low-voltage
halogen lamp may occur. If this happens, simply turn on
the lamp at 100% illumination for 10 minutes and the
black residue (the result of tungsten evaporation) will
nearly be eliminated.
Need additional assistance? Call the Lutron Technical Support Center 1-800-523-9466
Please provide exact model number when calling.
Dimming Low-Voltage Lighting
When dimming a low-voltage fixture, the dimmer con-
trols the line voltage (120VAC) input to the transformer
powering the low-voltage lamps. There are two types of
transformers manufactured for low-voltage lighting:
• Magnetic (core and coil) - MLV
• Electronic (solid-state) - ELV
Important: Before selecting a dimmer, determine
what type of transformer is in the lighting fixture.
Different characteristics of the two transformer types
require special dimming considerations. If you have a
question concerning what type of transformer a fixture
uses, refer to the fixture manufacturer's literature.
Note: Line voltage incandescent and low-voltage
fixtures can be mixed on the same circuit, but the
correct low-voltage dimmer (for the given low-voltage
load) must be used. The total load must not exceed the
dimmers capacity. Do not mix magnetic and electronic
transformers on the same dimming circuit.
Note: Some low-voltage fixtures cannot be dimmed.
Read the literature from the fixture manufacturer for
details.
Differences Between Magnetic and
Electronic Transformers
Magnetic:
Magnetic transformers step down 120VAC line voltage
to 12VAC or 24VAC. Magnetic transformers use copper,
wound around a steel core which is inductive by nature
(inductance is the ability of a device to store energy in
the form of a magnetic field). Magnetic transformers are
relatively large and heavy. Magnetic transformers are
primarily available in two types of construction; torroidal
and laminiated EI core. For these types of transformers,
use one of Lutron's magnetic low-voltage dimmers.
These products are rated in volt-ampere (VA), which is
explained in Dimming Magnetic Transformers on the
next page.
All MLV transformers should be equipped with a primary
fuse to protect against over heating.
Electronic:
Electronic transformers also step down 120VAC line
voltage to 12VAC or 24VAC. This is done with
electronic circuitry which is capacitive by nature
(capacitance is the ability of a device to store energy in
the form of an electric field). Electronic transformers are
compact and lightweight. Due to the higher efficiency of
ELV transformers, Lutron ELV dimmers are rated in
watts, which is the lamp load connected to the
transformer.
APPLICATION
NOTE
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