SERIES CAL7 Lighting Contactors
Compact contactors for North American lighting applications
Sprecher + Schuh CA7 and CA6 contactors can be used to control a wide variety of lighting loads. These contactors are well suited to handle the high inrush currents typical of this application as well as other non-motor (resistive) loads.
Lamps can basically be divided into three categories:
- Tungsten Filament Lamps
- General purpose incancdescent
- Special purpose incandescent
- Sodium Iodine
- Discharge Lamps (with Ballast)
- Fluorescent Lamps
- Mercury vapor
- High / low pressure sodium
- Halogen metal-vapor
- Mixed Light Lamps
The tungsten filaments of incandescent lamps have a very low ohmic resistance when cold. As a result, the closing current is very high but also very short.
The closing current of discharge lamps (lighting with ballast) is highly inductive (due to series-connected transformers or chokes), and its duration depends on the lamp type.
In general, North Americans refer to Lighting Contactor ratings in amperes without distinction between incandescent or ballast type of load. The lighting contactor selection table provided below is for North American use, so ratings are selected for mixed lamp loads which account for the higher incandescent inrush.
Europeans usually seperate the values for incandescent from discharge (ballast) lighting.
Electrically held contactors
Electrically held contactors are available for use where the control signal is activated by a timer or other maintained electrical signal. The coil is energized as long as the contactor is closed. This design is well suited for applications where lights are operated frequently or where the control panel is in a remote location.
Mechanically held contactors
Mechanically held contactors are available for applications where quiet operation or critical lighting is required, i.e., institutions, hospitals and residential/commercial areas. After the contactor closes, the voltage is disconnected from the operating coil and the contactor is held closed by the mechanical latch. Built-in clearing interlocks allow control from either a momentary or maintained pilot device for the seperate "pull-in" and "release" functions.