Crouzet Solid State Relay Knowledge Base

There are a number of different type lighting applications, but generally they can be broken into 4 types: incandescent, quartz, fluorescent, and HID.

Incandescent Lights
Characteristics are similar to resistive heaters. Significant inrush currents of 10x nominal current are common but easily addressed with zero-voltage turn on solid state relays. Ambient temperature and heat sinking carry the same significance for lamps as they do heaters, thus operation at lower temperatures increases reliability and life expectancy. SSR ratings of nominal current are recommended. Triac or SCR solid state relays may be employed successfully.

Quartz Lamps
Similar to incandescent lights, except that inrush current can be 20x nominal load-current rating and they often have a slight inductance. Zero-voltage turn-on, SCR output solid state relays are recommended for quartz lamp applications and, depending upon ambient temperature and heat sink, should be rated 2x the nominal load current rating.

Fluorescent Lights
Fluorescent lights are becoming more common in wide area lighting applications. SSRs can be successfully applied. Generally, electronic ballast lights can be controlled with zero-voltage turn-on, and traditional transformer/ballast type lights should use random turn-on solid state relays. If the SSRs are contained within the light assembly, they will operate at elevated temperature, and therefore should have at least 2x nominal current rating. Traditional transformer/ballast lights should also employ solid state relays with 2x the nominal voltage rating minimum to prevent electrical noise generated by the ballast from triggering the SSR into conduction.

High Intensity Discharge Lamps
HID lamps produce light by striking an electrical arc across tungsten electrodes housed inside a specially designed inner glass tube. This tube is filled with both gas and metals. The gas aids in the starting of the lamps and the metals produce the light once they are heated to a point of evaporation.

HID lamps produce a large quantity of light in a small package in comparison with incandescent and fluorescent sources. HID lighting is typically used when high levels of light are required over large areas and when energy efficiency and/or long life are desired. More recently, however, HID sources, especially metal halide (MH), have been used in small retail and residential environments.

HID lights generally employ capacitors for current limiting. In these cases, the effective load may appear capacitive or resistive. Zero-voltage turn-on is mandatory. Significantly elevated operating temperatures can be expected if the SSR is contained within the light housing with the supply ballast. Relays with 2x the voltage rating are recommended, and 3x to 4x the nominal current rating due to elevated operational temperatures and surge currents.

Typical Solid State Relay Lighting Applications;

Warehouse Lighting

Theatrical Lighting

Street Lights

Arena Lighting

Next Section

SSR Home
Knowledge Base
Downloads
Distributors
FAQ's
SSR CATALOG
Cross Reference Enter Competitor's Part#:


	SSR Applications
	Contact us
	Site Map
	Webmaster