Lamp Flasher – Belisha Beacon


This is a mains power lamp flasher control module.  Intended as a Belisha Beacon flasher but can be used to flash other lamps.

A Belisha Beacon an amber-coloured lamp atop a black and white pole, marking pedestrian crossings.  Common in New Zealand and several other countries.

Supply and delivery

We assemble these to order. Shipping/Delivery is typically 2 to 3 weeks from order.

Flasher Controller

mains power lamp flasherAssembled in two versions:

  1. Single-Channel:  This version has one output channel rated to drive 3 Amps of load
  2. Dual-Channel-Alternating:  This version has two output channels, each rated to drive 3 Amps of load.

Depending on the intended application, the controller may be supplied without the potentiometer.

Connection and Operation

mains power lamp flasherConnection

When mains power is applied, the flasher operates.  Mains power (Phase and Neutral) is connected to the left 2 terminals. The next pair (or 2 pairs) of terminals are Phase and Neutral connecting to the lamps. More than one lamp can be connected to each channel.  The maximum total load connected to each channel should not exceed 3 Amps (about 400 watts).

The mains supply should be protected by a fuse or circuit breaker. 6 to 8 Amps is recommended. Incandescent lamp failures present momentary short circuits causing a high fault current to flow. Appropriate protection will normally prevent damage to the flasher.

The terminals will accept reasonable sized wiring. Be sure to trim ends correctly so that excess copper is not exposed. Be sure that all strands are within the terminal and secure. Do not over-tighten the terminals.

The three terminal to the right are connected loop terminals which can be used to join earth wiring. An earth connection is not required for operation of the flasher, but may be required by the lamp fittings or electrical enclosure.

Operation

When mains power is applied, the flasher is operating.  There is a pulsing RED LED indicator from the right side of the DIP-Switch.

The potentiometer controls the flash rate between about 0.5 seconds and 3.5 seconds.  But if DIP-Switch 1 or 2 are ON, the flash rate will be about 43 flashes per minute, overriding the potentiometer.

The DIP-Switch has 2, 3 or 4 positions:

  1. Belisha Beacon mode. 43 flashes per minute, 50/50 % duty cycle (overrides potentiometer setting).
  2. Belisha Beacon mode. 43 flashes per minute, 33/66 % duty cycle (overrides potentiometer setting).
  3. not used – defaults to same setting as position 1
  4. not used – defaults to same setting as position 1

NOTE: The effect of changing the DIP-Switch or potentiometer settings may be delayed slightly as the current flash cycle completes.

Technical

mains power lamp flasherThe flasher electronics is fully enclosed except for the connection terminals. Several ventilation holes on the back and sides allow some air-flow and ventilation of the internal heat-sink.

Ratings and features:

  • Do Not get wet
  • 110V to 240V AC, 50 or 60 Hz
  • 6A total load or 3A load per circuit
  • Fuse mains supply at 8A maximum
  • Earth connection not required by flasher
  • Power draw without load < 1 watt
  • Ta: 40 deg-C,  Tc 70 deg-C
  • Triac based zero-crossing switching (includes snubber components)
  • supports resistive and inductive loads
  • Flash rate adjustable 0.5 to 3.5 seconds
  • Pre-set Belisha-beacon modes: 43 flashes per second, 50/50 or 33/66 duty cycle
  • Plastic panel mounting enclosure – high-impact ABS plastic UL94V0
  • Overall dimensions 92x118x30 mm – mounting hole centres 50x105mm