Green Light Power Switching
Crestron Commercial Lighting Design Guide
Green Light Power Switching
Panels (MLO) Main Lug Only and (MCB) Main Circuit
Breaker Zero-Cross Arcless Relays
The GLPS-HSW Power Switching Panels come standard
with 20A branch circuit breakers, and accept 208Y/120 or
480Y/277 volt feeds terminating to main lugs provided. An
optional back-fed main circuit breaker may also be specified.
Four panel sizes are available, dubbed
The panel size is ordinarily
determined according to the number of control circuits
specified, ranging from 8 to 42 circuits per panel. Each
control circuit is rated for 16A at 100-277V.
The GLPS-HSW panels utilize Crestron zero-cross arcless
relay technology, achieving a relay lifetime of one million
cycles. A high-current triac is employed to handle the
high-inrush current turn on, especially with certain load
types such as HID and electronic ballasts. Within
milliseconds, the continuous load is transferred to a
robust 50A mechanically-latching relay. All switching
occurs at the zero-cross point of the AC waveform under
microprocessor control. This is a complete solution
eliminating arcing at the physical relay contacts
and turn off, and supports switching of all types
of lighting loads
up to 16A at 100V to 277V, as well as
motors up to 1 HP.
As an option, GLPS-HSW panels may be equipped with 0-10V
fluorescent dimming control substituted in place of some or
all switching circuits. Consult Crestron Sales Support
Services to specify this option.
The GLPS-HSW panels employ field-replaceable lighting
control modules, with 8 or 12 control circuits per module,
for excellent configurability and serviceability. Each module
includes local relay controls and load state indicators for each
circuit, plus additional controls and indicators for use during
Individual hinged doors are provided on the front of each
GLPS-HSW panel for access to the circuit breaker panelboard
and the local controls on each module. As an option, the local
control access door may be omitted.
As part of a complete Green Light system, GLPS-HSW
panels connect to an IPAC-GL1 lighting control processor
(or other 2-Series control system) via the Cresnet
control network. An optional GLA-PWS50 (or equivalent)
power supply is also recommended for each panel to provide
backup power to the lighting modules.
Remote emergency override mode allows the lighting system
program to be overridden while each circuit is set to an
override preset state. The override preset for each circuit is
set using the local controls on the front of each lighting
module. Remote override mode is activated by an external
contact closure from a Crestron GLS-PLS-120/277 power
loss sensor or other device.
All low-voltage connections to a GLPS-HSW panel are made
via a connector block located near the bottom of the panel.
Connections are provided for Cresnet communications,
backup power supply, and emergency override.
Crestron Green Light Power Switching panels are configured
to order, factory assembled and tested prior to shipping. Each
panel is engineered to provide a clean and manageable
installation with provisions for wire termination and conduit
knockouts. On-site installation is fast and easy with all
termination points clearly labeled and accessible from
Specifying and ordering a Crestron Green Light Power
Switching panel is facilitated using the following model
number system. Simply fill in the appropriate entry in each
position according to the steps that follow:
GLPS-Relay Type-Feed Type-Number of Ckts-Voltage-AIC Rating-Door Option
The above example is for a
Main Lug Only
panel with 30
zero-cross arcless relays, 120V / 10kAIC circuit
breakers, and no local control access door.
Relay Type: Enter
to specify zero-cross arcless
Notes: For other relay types, refer to the Selection Guide
0-10V fluorescent dimming is also available. Consult Crestron
Sales Support Services to specify this option.