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SCCR or S.C.C.R. or Short Circuit Current Rating

SCCR or “short circuit current rating” is a rating of how much over-current a device can take without injuring equipment or personnel. SCCR is applied to a passive device such as a relay that doesn’t have its own way to “open”. 



Specific setting for a group of dimmer channels or zone. A multi-scene control allows you to select the different setting by pushing a button.

The lighting effect created by adjusting several zones/channels of lighting to the desired intensity.



A component used to determine the an environmental condition or value of a physical system variable.


Example: RS Sensor



The mode during which preset lighting scenes change in a designated order using fade times that have been programmed.



A device in a networked system acting as a provider of data, responding to a request from a client.


services, bacnet

The method by which one BACnet device gets information from another device, commands a device to perform certain actions, or lets other devices know that something has happened.


Setpoint Optimization 

A control strategy that optimizes the setpoint of a source piece of equipment that supplies one or more receiving units - such as an air handler unit supplying zone terminal units with heating, cooling, ventilation, or similar service.

The source unit communicates with receiving units to determine heating, cooling, and other requirements, and then adjusts its setpoint.

For example, if all zones are comfortable and do not request cooling, the AHU will gradually increase (trim) its supply air setpoint. When a zone requests cooling, the AHU responds by dropping its setpoint. The more zones that request cooling, the more it drops the setpoint. The AHU repeats this process throughout the day to keep zones cool, but with a supply air setpoint that is no cooler than necessary.



ShortStack is technology from Echelon used to LonWorks-network-enable any microprocessor-based device. The device's application uses the ShortStack API and the hardware includes the ShortStack Micro Server.


Slide Dimmers

Slide dimmers operate via a slide toggle, providing a full-range of manual dimming control. Some are equipped with a touch-button that allows you to return to the previous lighting level. Others have an indicator light that glows in the dark for easy location.



Acronym for Serial LONTalk Adapter.



Sheet Metal and Air Conditioning Contractors National Association, Inc. is an international association of HVAC contractors. Its headquarters is at 4201 Lafayette Center Drive Chantilly, Virginia 20151-1209, and it has about 2,000 members and 98 chapters in the United States, Canada, Brazil, and Australia.

Sheet Metal and Air Conditioning Contractors National Association, Inc.

4021 Lafayette Center Drive
Chantilly, VA 20151-1209


Smart Actuator (SA)

An actuator which is controlled by a network connection rather than a binary or analog signal. (0-10v, 4-20mA, relay, etc.)


Smart Sensor (SS)

A sensor which provides information to the BAS via network connection rather than a binary or analog signal. (0-10000 ohm, 4-20mA, dry contact, etc.)

SNVT - Standard Network Variable Types

A method utilized by LON that is a standardized way of communication uses a discreet list of variable types to set or change various outputs such as temperautre in a controlled space and allows building automation systems to monitor output variables such as room and duct humidity readings, heat output, and service information.


Solid State

Electronics that use semi-conductor chips and circuitry.


Solid-state electronic components, devices, and systems are based entirely on the semiconductor, such as transistors, microprocessor chips, and the bubble memory. In solid-state components, there is no use of the electrical properties of a vacuum and no mechanical action, no moving parts, although a considerable amount of electromagnetic and quantum-mechanical action takes place within.


In a solid-state component, the current is confined to solid elements and compounds engineered specifically to switch and amplify it. Current flows in two forms: as negatively-charged electrons, and as positively-charged electron deficiencies called electron holes or just "holes". In some semiconductors, the current consists mostly of electrons; in other semiconductors, it consists mostly of "holes". Both the electron and the hole are called charge carriers.


Surface Mounted

Surface-mounted fixtures are also know as ceiling mounted fixtures. They attach directly or close to the ceiling. The light distribution is often semi-direct or general diffuse.


Switch Leg

Wiring that connects the switch or dimmer output to the fixture or load being controlled.