Hummingbird Electronics’ GPS Speed Switch provides a simple to install, calibration free speed based switch.


Additional Information – HMSW1000B Rev1.1

Hummingbird Electronics’ GPS Speed Switch provides a simple to install, calibration free speed based switch.

Speed thresholds are set using internal switches in either km/h or mi/h.

Using data received from the Global Positioning Satellite network, the GPS Speed Switch calculates three-dimensional ground speed. If the speed exceeds the threshold, relay contacts switch, providing the installer with maximum versatility.

This high technology solution eradicates the dependency on vehicle specific parameters, thereby reducing installation time and eradicating the need for periodic calibration

Speed Switches have traditionally used speed-signals derived from gearbox mounted hall-effect or inductive speed senders. The Hummingbird Electronics’ speed switch integrates the source of the speed signal with the switch resulting in a small, reliable solution. No calibration is required and operation is completely independent of the vehicle.

Three dimensional velocity calculations are accurate to 0.2km/h and are updated 10 times per second. A 50 channel satellite receiver, enhanced receiver sensitivity and active antenna result in fast time-to-first-velocity-calculation as well as the ability to operate in the harshest RF environments such as canyons and cities.

Last known position and satellite information critical to fast start-up are battery backed in case of power failure.

A voltage free relay output with common(30), normally-open (87) and normally-closed (87A)terminals is provided. At low speed, the common contact is connected to the normally closed contact and when the speed set point is exceeded, the common terminal will be switched over to the normally open contact.

Designed for harsh automotive environments, the module features transient voltage protection on the supply and short circuit protected outputs.

GPS Speed Switch is supplied in a rugged aluminum enclosure with provision for screw mounting when required. Antenna connection for the active antenna is provided through a gold-plated threaded SMA connector.

The active antenna is available in two options:

  • magnetic mount, suitable for mounting in the interior of the vehicle, for example under the dashboard or rear window sill.
  • bulkhead mount, suitable for exterior mount, for example on the roof of the cab.

For optimum performance, the antenna should be mounted horizontally and upright; and should have a clear view of the sky.

A red LED is provided to give the user status information.

Power to the unit and switch outputs are provided through four colour coded wires.

  • Input voltage: minimum 9V, maximum 36V
  • Power consumption: 480mW (incl. antenna)
  • Relay current: Internal resettable fuse: 1A
  • Acquisition time, loss of lock: less than 2s (90% of the time)
  • Acquisition time, temp loss of power: less than 10s (50% of the time), less than 13s (90% of the time)
  • Acquisition time, power-up: less than 38s (50% of the time), less than 42s (90% of the time)
  • Accuracy, horizontal: less than 5m (50% of the time), less than 8m (90% of the time)
  • Accuracy, altitude: less than 10m (50% of the time), less than 16m (90% of the time)
  • Precision, velocity: less than 0.06m/sec or 0.22km/h
  • Update rate: 4 times per second (4Hz)
  • RF interface: SMA connector supplied on magnetic and bulkhead antenna versions
  • General: 50 channel tracking receiver, battery backup 12 days

Physical Characterisics

  • Size: 57mm (width) x 82mm (length) x 35.2mm (height)
  • Antenna dimensions(mm): 51(l), 42(w), 12(h); cable length 5m

Environmental Specifications

  • Operating temperature: -40°C to +85°C
  • Storage temperature: -55°C to +105°C
  • Humidity: 5% to 95% R.H. non condensing at 60°C

Power Output

  • Red: input voltage (6V to 35V)
  • Black: ground (0V)
  • Yellow: normally-open circuit, pulls low if speed exceeded
  • Green: normally-closed, goes open circuit when max speed exceeded

Switch Settings

  • SW10: ON = miles per hour, OFF = kilometers per hour
  • SW9: Spare
  • SW8-1: Switching speed = SW1+2*SW2+4*SW3+8*SW4+16*SW5+32*SW6+64*SW7+128*SW8

Example: speed 35km/h – SW10=OFF for km/h; SW6 = ON (32), SW2 = ON (2), SW1 = ON (1); 32+2+1 = 35 Note: If GPS lock is lost, the unit will default to zero speed