Benefits and Features

• high performance, high energy transmission
• safety class 1 (no additional protection required)
• low beams divergence
• high sensitivity receiver
• robust design for operation in harsh environments
• longevity, maintenance free

General Description

Gordy’s HD Laser light barrier systems HLS with a range of up to 800 m are suitable for long range perimeter protection and applications in severe industrial environments, where adverse conditions like dust, smoke, steam or heat prevail.

The laser light barrier system HLS comprises a transmitter unit and a choice of three receiver units. The transmitter unit contains a semiconductor laser device, which emits light pulses at a fixed pulse repetition rate, as long as the supply voltage is applied.

When a system is set up and aligned, these light pulses are picked up by the highly sensitive photodetector in the light barrier receiver unit and the integrated alarm relay is switched to the ‘Alarm Off’ state. If the connection between the transmitter and receiver is cut off by an object moving into the optical path, or if there is a technical defect in the electronics or in the power supply, the alarm relay switches to the ‘Alarm On’ state.

The use of a semiconductor laser transmitter and a highly sensitive photodetector guarantees reliable operation, even under extremely difficult conditions. Due to the incorporated high quality optical filter in the receiver unit even high background illuminations, e.g. due to the sun or white hot steel, does not lead to a degradation of functionality.

For applications requiring a short response time, the receiver HLS-T reacts in a fixed time of approx. 2 milliseconds. The standard receiver HLS enhances the advantages of the system, by offering the possibility to delay the activation of the alarm relay. By delaying the response time of the alarm relay, between approx. 10 milliseconds to about 1 second, it is possible to avoid false alarms and consequential costly interruptions of production due to the loss of a few inconsequential light pulses.

An additional increase in operational safety is offered by the receiver HLS-K. During operation in adverse environments, the optics of the transmitter and receiver units will be covered, in a not definable time, by a dust layer or a dirt/oil film which reduces the initially high power margin. When the received power then falls to near the detection threshold of the photodetector, even small changes in operating condititions might result in sufficient pulse losses to provoke false alarms and again costly interruptions of production.

To avoid this the HLS-03K receiver features an independent ‘Pre-Alarm’ function. If the strength of the received optical signal falls below an individually adjustable threshold, well above the ‘Alarm’ threshold, an ‘early warning’ signal is activated, that can be used to alert maintenance staff. By setting the ‘Pre-Alarm’ threshold with a sufficient margin to the fixed ‘Alarm’ threshold, false alarms can be avoided and maintenance cycles kept to a necessary minimum.

The careful selection of materials and components and the use of rugged stainless steel housings and armoured silicone cables with stainless steel braiding, ensures troublefree operation even under most severe conditions.