Obstruction Lamp Alarm Relay Series - Obstruction Lamp Alarm Relay

External overview image
Roll Over to Zoom
Disclaimer Notice

Littelfuse products are not designed for, and shall not be used for, any purpose (including, without limitation, automotive, military, aerospace, medical, life-saving, life-sustaining or nuclear facility applications, devices intended for surgical implant into the body, or any other application in which the failure or lack of desired operation of the product may result in personal injury, death, or property damage) other than those expressly set forth in applicable Littelfuse product documentation. Warranties granted by Littelfuse shall be deemed void for products used for any purpose not expressly set forth in applicable Littelfuse documentation. Littelfuse shall not be liable for any claims or damages arising out of products used in applications not expressly intended by Littelfuse as set forth in applicable Littelfuse documentation. The sale and use of Littelfuse products is subject to Littelfuse Terms and Conditions of Sale, unless otherwise agreed by Littelfuse. "Littelfuse" includes Littelfuse, Inc., and all of its affiliate entities.

The SCR490D is used to provide remote monitoring of steady burning incandescent marker and obstruction lighting. Four onboard switches allow operator programming for lighting systems with two through nine lamps on a single AC circuit. The SCR490D uses a toroidal sensor and electronic circuitry to sense the failure of one or more lamps.

Operation
When a lamp fails, the SCR490D senses a decrease in current flow. Then, after a fixed time delay, it transfers to its alarm mode. In alarm mode, the LED indicator, the output relay (SPDT isolated contacts), and a non-isolated solid-state output are energized. Replacement of the failed lamps resets the alarm outputs and the LED indicator. To prevent false alarm signals, power must be applied

Access specifications, certifications, check availability and order parts below

Catalog #Input
Voltage (V)
Output VoltageOutput
Form
Trip Delay TypeOutput Load Rating (VA)DimensionsStockSamples
SCR490D120 V ac≤125 W @ 120 VacSDPT≅6 fixed10 A @ 240 Vac or 30 Vdc resistive; 1/4 hp @ 125 Vac; 1/2 hp @ 250 Vac3.5 H x 2.5 W in. (88.9 x 63.5 mm)CheckOrder
To request product environmental information, please complete the Product Environmental Information Request Form.