Littelfuse SCR9L Series, Universal Lamp Alarm Relay, Output Form SPDT, 120-230VAC

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Regular price $449.42
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The SCR9L is a universal lamp alarm relay designed to sense the failure of flashing or steady LED beacon lamps or obstruction lamps. The SCR9L energizes when one or more lamps fail. It will monitor the operation of one to eight beacon or obstruction lamps. All monitored lamps must be the same wattage and voltage. When connected to a site monitoring system, it provides the remote lamp monitoring protection required by the FAA-AC No: 150/5345-43E.


When a lamp fails, the SCR9L senses a decrease in current flow. After a 10s trip delay, the onboard LED glows and the two alarm outputs energize. The outputs and the LED are reset when the failed lamps are replaced and the unit is recalibrated. The SCR9L will sense an open flasher, it will not sense a continuously ON flasher (see FB Series). Removing input voltage de-energizes the output and the LED‘s. It does not change the calibration.


Calibration Range (total all Lamps) 150mA - 8.0A
Absolute Max Current (total all Lamps) 15A max. (may not calibrate above 8A)
Single Lamp Current 150mA - 8.0A (total all lamps < 8.0A)
Time Delay
Trip Delay Factory fixed ≅10s
Input Voltage/Tolerance 120 to 230VAC ±15%
AC Line Frequency 50/60Hz
Output To operate a spare lamp or alarm
Line Voltage Output (SPNO) 5A @ 240VAC or 30VDC resistive;
1/4 hp @ 125VAC; 1/2 hp @ 250VAC
Isolated Alarm Output (SPDT) 10A @ 240VAC or 30VDC resistive;
1/4 hp @ 125VAC; 1/2 hp @ 250VAC
Auxilliary Input Voltage (H) ≤ 2A @ 230VAC
Mounting One #10 (M5 x 0.8) screw
Dimensions H 76.7 mm (3”);
W 51.3 mm (2.02”);
D 41.7 mm (1.64”)
Termination IP20 screw terminals for up to 14 AWG (2.45 mm2 ) wire or two 16 AWG (1.3 mm2 ) wires
Circuitry Encapsulated
Operating / Storage Temperature -40° to 60°C / - 40° to 85°C
Weight ≅ 3.9 oz (111 g)