Crosby BlokAlert

BlokAlert is a warning system developed by Crosby Blokcam. When BlokAlert is activated, the BlokAlert receiver gives an easy recognizable audio-visual signal, that can be seen and heard by on site personnel in immediate proximity to the hook or load. This gives a warning to the workforce about the position of the hook block, which also reduces the risk of accidents involving the hook, lifting accessories or load.  

Why BlokAlert?  

Traditionally the distance between the load and the horn, which is often located near the operator’s cab, does not warn the site personnel to the position of the hook or load efficiently enough. That also applies to airhorns or whistles when the are used by riggers. In both scenarios the attention is immediately pulled to the sound and not to the actual hazard.  The solution is to fit a warning system to the hook block. When that is activated, the attention immediately goes to the hazard, not away from it.  

View more about the wireless camera system from BlokCam here.

See BlokAler 'in-action' in the video above. If you cannot see the video - then you simply have to accept the necessary cookies.

BlokAlert  - Wireless warning system with sound and light

How does BlokAlert work?

In the cab:  

The transmitter is activated by a foot switch in the cab. When the foot switch is activated, it sends a signal to the receiver on the hook block.  

On the hook block:  

When it receives the signal from either the foot switch in the cab or the included remote controls, the receiver is activated and starts warning people with both audio and light.   

BlokAlert can be used on all crane types.   

BlokAlert - oversigt


  • Powerful neodymium magnets for installation 
  • Easy to install, remove and charge 
  • Two hand-held transmitters per system 
  • Multifunction operation makes it easy to use 
  • 2 x 78db Electronic Sounders 
  • 180° LED beacon with four colors  
  • Use button to pair receivers 
  • Long range receiver and transmitter (range depends on the surrounding environment) 
  • Built-in Lithium-Ion battery with 124-hour battery life (battery life is depended on use and configuration) 
  • Built-in foldable carry handles 
  • Special-built aluminum house  
  • Built-in safety tether to provide additional security  
  • LED power indicator 
  • Low profile design of only 86mm 
  • Durable design for all types of weather – made for IP67 rating 
  • Operating temperature: -10°C to 50°C (14°F to 122°F)   
  • CE and FCC approved 

What is included in the BlokAlert-system?


Together with the LED-Beacon, the BlokAlert receiver is capable of giving up to 528 different audible alerts. This audiovisual warning system combines great functionality, performance and design making it a must for all lifting tasks.

Size and weight: Height: 173 mm Width: 210 mm Depth: 86 mm Weight: 3400 g.

Crosby BlokCam X2 sender


BlokAlert remote control allows riggers to operate multiple BlokAlert systems across the work area.

  • Two x 4 buttons per system.
  • Robust design complete with lanyard.
  • Remote controls with 8 and 16 buttons are available on request.

BlokAlert Remote

Accessories for BlokAlert


BlokAlert-BA-T2 gives via the footswitch the crane operator hands free use of the BlokAlert system.

BlokAlert BA-T2-Transmitter


For hands free opretation. Easy to install.

BlokAlert FS1-footswitch

Do you have questions about the BlokAlert products?

Contact us

Get a call

Get a call

Frank Nørlem

Salgs- og uddannelseskonsulent


Frank Nørlem

Joachim Riisager




Joachim Riisager