Tower Light Monitor - LED

Monitor Steady or Flashing LED Beacon Lamps

The TLM-LED is a universal lamp alarm relay designed to sense the failure of flashing or steady LED beacon lamps or obstruction lamps. The TLM-LED 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 properly integrated with ARC Plus or ARC Solo systems, it provides the remote lamp monitoring protection required by the FAA-AC No: 150/5345-43E.


When a lamp fails, the TLM-LED 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. Removing the input voltage de-energizes the output and the LED‘s. 


3” (7.67 cm) H
2” (51.3 cm) W
1.64” (41.7 cm) D

Operating Temperature:

-40° to 60°C
Input Voltage:
120 to 230VAC ±15%

AC Line Frequency:


Line Voltage Output:

5A @ 240VAC or 30VDC resistive;
1/4 hp @ 125VAC; 1/2 hp @ 250VAC
To operate a spare lamp or alarm

Isolated Alarm Output:

10A @ 240VAC or 30VDC resistive;
1/4 hp @ 125VAC; 1/2 hp @ 250VAC


One #10 (M5 x 0.8) screw


Screw terminals for up to 14 AWG
(2.45 mm2) wire

Trip Delay:

Factory fixed ≅10s



Ordering information

Part #Product
TLM-LEDTower Light Monitor - LEDRequest quote

Key Features

  • Monitors LED lamps for failure
  • Designed for use with all types of LED beacon and obstruction lamps
  • Number of lamps monitored is switch selectable up to 8
  • 10A isolated SPDT alarm output contacts
  • Provides visual relay status of operation, alarm, trip delay, and calibration
  • Self-calibrating