Safety Light Curtains with Advanced Bluetooth Interface

Safety light curtains, or as they are often known as – light barriers, light grids and light guards to mention just a few alternatives are classed as Electro-sensitive Protective Equipment. Consisting of a transmitter and a receiver head, light curtains generate a field of infrared light between these heads which is classed as the detection zone.

Invisible Light Protection

Typically, these diligent devices are situated around access points to a piece of processing machinery, shutting down the device should a person, or a part of a person, cross the beams of the safety grid.  Advantages of a light curtain include reduced operator fatigue, when compared to mechanical options such as gates and barriers, and the subsequent upkeep of these mechanisms and simplifying maintenance and set-up times.

safety light curtain installation

Utilised across numerous industry sectors for many years, light curtains come in many shapes and sizes. Schmersal, renowned for their impressive range of Safety Light Curtains decided to add yet more functionality to these popular process safety devices by adding a built-in high specification Blue Tooth interface.

The Schmersal SLC440/COM Safety Light Curtain range with built-in Bluetooth BLE (BLE stands for Bluetooth Low Energy) is an active optoelectronic protective device that can provide real-time status and diagnostic data of the light grid on a smartphone or a tablet via a Bluetooth interface.

Ideal for Predictive Maintenance

The Bluetooth interface allows easy start-up using a smartphone or tablet with the integrated set-up aid. There is also the useful option of saving the data, which can then be used to document a repeat test or for predictive maintenance purposes. The transmission of data to smartphones / tablets (Android, IOS) is facilitated by an app developed by Schmersal.

NFC technology has been used successfully in the past when it came to recording and monitoring device diagnostic data, however it is limited to only a few centimetres. The Bluetooth BLE interface contained within the SLC440/COM Light Curtains can achieve a range of up to 100 times more, around 5 metres in total.

This means the BLE interface is perfect when the safety light curtain installation is in a relatively inaccessible position. Bluetooth BLE also offers a greater range of applications because not all smartphones or tablets are equipped with NFC. As Bluetooth is an international industrial standard, the SLC440/COM range can be used all over the world.

safety light curtain installation

Safety and Efficiency

The SLC440/COM Safety Light Grid with BLE are ideal for improving efficiency and availability in manufacturing processes as their status can be accessed easily and in real-time, meaning issues can be captured early. Status information and diagnostic data enables processes to be reactivated quicker, particularly in the event of a system shutdown if a hazard is detected.

It also represents an economical innovation as, compared to classic Bluetooth, BLE is characterised by considerably lower energy consumption and reduced costs at a similarly high communication range.

All of the SLC440/COM range of light curtains are available from Kempston Controls, give our sales team a call on +44 (0) 1933 411 411 or email them at, or use the enquiry form below and let us help you select your ideal light curtain solution.

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deTec Safety Curtains

Motor control and monitoring


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deTec by SICK

deTec safety light curtains from SICK: taking safety to the next level

SICK’s new generation of deTec safety light curtains is ideal for the protection of hazardous areas, and entrances. Utilising intelligent, state-of-the-art technologies such as NFC and IO-Link the deTec range provides comprehensive diagnosis, fast installation, and automated functions.

deTec Safety Curtain

The entire deTec product family use standardised connectivity and compatible accessories to reduce variant diversity and ease of use. Functionality can be activated using an appropriate M12 plug, reducing the need for additional software. What’s more, with IP65, IP67, and IP69K enclosure ratings on certain variations, plus options for ATEX areas, the SICK deTec safety light curtain range is up for any task.

deTec at a glance

  • NFC for smart and easy diagnosis
  • Diagnostics and automation via IO-Link
  • 2-signal muting
  • Smart presence detection
  • Configuration of all functions without software
  • Reduced resolution: 1 or 2 beams
  • IP65, IP67, and IP69K enclosure ratings plus variants for explosion-hazardous areas

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Benefits of the deTec range

  • Extensive and innovative diagnostic options leading to increased productivity and shortened downtime
  • Cost-effective system design thanks to IO-Link: safety and automation combined
  • 2-Signal muting offers maximum productivity and safety and can differentiate between people and material
  • Smart presence detection to ensure the deTec range is always working to prevent unwanted switch-offs
  • Easy commissioning and configuration without the need for software, saving time and money
  • IP65, IP67, and IP69K enclosure ratings available, plus variants for ATEX areas, ensuring maximum reliability in harsh environments

Stop! Danger Sign

deTec: Ready for anything

Thanks to the rugged and reliable design of the 3GD variants’ housing, they are ideal for use under the strict safety requirements found in explosion-hazardous areas. With the ability to be cascaded, the deTec range saves space and offers all-round flexible protection with no blind spots.

The Ex range, in pressure-resistant explosion-proof enclosures, goes a step further and are approved in accordance with ATEX, IECEx and NEC. Pre-wired and fully mounted in the housing, the complete system is also UL-certified and represents a truly outstanding product that is ready for anything.

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Kempston Controls isn’t just a place to come to find the best Automation and Process Control products with the best possible prices and service, we are also the people to speak to when you need to find an answer to your processing conundrum. We are in close contact with all of the leading suppliers and can get you the best possible products to meet your systems requirements. Give us a call today on +44 (0) 1933 411411 or email us at to discuss your installations requirements.

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Sick Old Model Light Curtains Phase Out

Infographic: Hearing Protection

Sick Old Model Light Curtains Phase Out – Last Chance To Order: September 2021

Due to developments in technology, SICK C4000 Standard & Select, M4000 Standard & Area 60 and the deTec4 Prime Safety Light Curtains are being phased out. Please note that September 2021 is the last chance to order and their end of life is planned for December 2024. All other variants of these product families will still be available as they are not part of the phase-out.

The good news is that SICK’s deTec product family is fully compatible with all the light curtains being phased out by using suitable mechanical and electrical adaptors.

light curtain phase out

Making the change to the deTec safety light curtains ranges ensures you can take advantage of a host of innovative safety functions to improve your productivity. Use intelligent and modern technologies like the NFC1 and IO-Link2 and enjoy the benefits of extensive diagnostic functions and simple connection-compatible installation.

Learn More and read about the full range of benefits by downloading the brochure.

To identify the correct replacement product or to get more information about the deTec product family contact Kempston Controls today. As SICK supplier partners we have access to their entire range, call us on +44 (0) 1933 411411 or email to discuss your SICK Light Curtain options.


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Quick-Guard ABB Fencing

Quick(!)-Guard your assembly lines and hazardous areas.

Designed to be flexible, the Quick-Guard fencing system is ideal for a variety of applications from machine enclosures to preventing access to hazardous areas.

Consisting of different components, such as aluminium profiles, patented assembly parts, netlocks, mesh, solid or noise reduction panels the Quick-Guard system can be tailored to meet any requirement.

Thanks to ABB’s patented screw-lock system, all the brackets are supplied premounted with fixing screws and nuts. Due to the profile’s T‑slot, assembly and any further modifications can be easily made.

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Quick-Guard at a glance

Easy to install

  • Lightweight aluminium profiles allowing for ergonomic assembly.
  • Premounted brackets with a patented screw-lock system to simplify assembly.
  • Easy to modify an existing fence design since the aluminium profiles are easy to saw into different lengths.

Speed up your projects

  • Endless possibilities with numerous materials and components
  • Quick-Guard fencing has fittings and mounting brackets for sensors, locks and switches from the ABB Jokab Safety range.
Quick-Guard Fencing


ABB’s Quick-Guard fencing system has been designed to be used in a multitude of applications and can easily be customised to suit any requirement. Quick-Guard can be supplied in two formats: Quick-Guard Express and Quick-Guard Standard.

Quick-Guard Express can be installed quickly and is ideal as a cost-effective fencing solution. The customer orders ready-made sections consisting of a few components which makes it easy to install on-site.

Quick-Guard Standard is more advanced than the Express version and uses a sketch or an AutoCAD file of how the user wants the fencing system to look. The information is then transferred to SafeCAD (ABB’s free AutoCAD plugin) and a 3D model of the user’s requirements is rendered with cutting, component lists and quotations automatically generated.

What’s more, these two fencing systems can be combined to achieve a complete system.

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Quick-Guard in use

Patented assembly function

ABB’s patented guide and locking method allows for simple assembly while keeping expansion easy. The integrated fixing nut can be easily be located within the profile and automatically positions itself when the screw is turned 90 degrees clockwise to allow adjustments. While the fixing nut is in this position, the bracket being fitted can be adjusted and then locked by turning the screw clockwise. To remove the bracket the fixing screw is turned counterclockwise.

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Customisable and integrated components

ABB offers a wide range of sensors and control devices specifically designed for the Quick-Guard fencing system. Devices such as Sensors, light grids and emergency stops are easy to mount, adjust and dismount thanks to the profile’s T‑slot and special nuts. The patented assembly means no holes have been drilled so there’s no holes or damage when adjustments are made – keeping the system professional, safe and secure.
Integrated components available:

  • Eden – Non-contact sensor – (3)
  • Orion – Optical safety device
  • Smile/Inca – Emergency Stop
  • ASK – Pressure-sensitive safety mats
  • Contactors & electronic starters
  • Magne – Magnetic process lock – (1)
  • MKey – Mechanical key switch
  • EStrong – Emergency stop
  • GKey – Safety lock
  • Dalton – Process lock – (2)
  • Knox – Safety lock – (4)
Quick-Guard and Components

The Quick-Guard fencing system from ABB is the ideal solution for protecting machine enclosures and more. To find out how the solution could work for your application, contact Kempston Controls today on +44 (0) 1933 411411 or email us at

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“Say ATEX RATED!” – The Cube 800: Intrinsically safe camera and thermal imager

Safety Relays – Keeping an Eye on Machine Safety


Safety Relays, as the name suggests, are, generally, devices that have been designed into a production process of some kind to implement safety functionality should a trigger event or error in the manufacturing processing activity occurs.

When the safety relay is triggered by an activation signal or when it detects a failure within the safety network, it will initiate a safe and reliable response which should help reduce the outcome of any potential risk to persons or the process devices themselves to a negligible level.

With an array of safety relays designed into a system and each one monitoring a specific function, you can achieve a very high level of plant and machine monitoring. Adding these devices into your processes is an efficient way of ensuring systems and personnel are protected adequately and any potential risks are reduced to a minimum.


Basic functions of Safety Relays in Industry

  • Status and monitoring of movable guards that open or close for access to machinery
  • Controlling a powered guard system, preventing access until machinery has halted
  • Emergency stop functionality – two-handed operation functions
  • Stopping a conveyor, motor, press or other devices in a controlled safe manner

Assessing the Risks

It’s no small stretch of the imagination to envisage just how dangerous unguarded machines and processes can be, press tools, conveyor belts, bailers, CNC machines etc. are all powerful machines that could cause serious injuries. Of course, it’s not only the power of a machine that has to be considered, but noise and vibrations, heavy material, fumes and sharp implements are all cause for concern, basically, everything that could cause harm or damage to a person or process machine is a risk.

What this all means is that when you are designing a new installation, processing machine or some form of automated system you will need to find and assess all the possible risks that could occur during its use and then aim at reducing or eliminating them.

Trying to establish all of the issues of concern within your intended installation can hard to fathom, some will be blatantly obvious but others could arise from operators circumnavigating safety protocols or from issues relating to mechanic failure.  Either way, once you have done your very best to evaluate all of the potential areas of concern you then have to design safety mechanisms into the installation, items such as interlocks, light curtains and emergency stop buttons etc.

However hard you may try there is always the possibility of your safety system failing, for example, an operator accesses a guard door and the safety interlock doesn’t work correctly leaving the machinery still functioning. The safety system you so diligently built into the process has failed to eliminate the danger, so you have to analyse all of the potential risks for all the aspects of your safety control systems. Basically, you want the safety system to be safe even when aspects of it are failing or have failed and that’s where a safety relay comes in, monitoring the safety functions of your systems and checking for issues within the network.

Monitoring the Safety Network

You would be hard pressed to find any industrial manufacturing process or application such as a theme park ride that doesn’t feature safety relays within its safety monitoring network. Heavily regulated, there is a stringent set of standards to adhere too, OHSAS 18001 – replaced by ISO 45001 in 2018, that has been designed to help protect those who encounter these installations and machines, wherever they may be located.


Common Failures

  • A break in a wire
  • Faulty and failing contactor
  • Safety interlock failure


The above list makes up the majority of common issues you may encounter in your application, there are certainly others that you may come across of course. One thing, however, that all of these issues have in common is the method by which they are detected. A safety relay issues a series of small timed electrical pulses through the wiring network and determines from the flow of current and pulse timing if the safety devices are failing or have indeed failed, perhaps via a break in a wire or maybe a contactors contacts have welded together.

Safety Relays in Action

Light Curtains – utilised to protect personnel from injuring themselves when in close proximity to potentially dangerous machinery. When the infrared beams of these devices are broken by a passing object or person a stop signal is generated.

Safety Mats – these detect the presence of weight on their active surface, which can be utilised for a number of purposes, such as triggering a stop command when activated or as a supplementary switching device that initiates a light curtains mute function to allow access.

Two Hand Control – these devices insist on the use of both of the operator’s hands to activate a switching device, ensuring they can’t reach into any dangerous areas of machinery during its operation.

Emergency Stop – perhaps the most common control device available in a variety of guises, from the traditional red button within a yellow housing to variants that include a grab-wire allowing you to activate an emergency stop at any point on a process line.

Interlock switches – available in multiple forms, from spring-locking to electrical and air operated, these detect when safety components such as machine guards are in place and can lock to prevent them from opening.

Magnetic switches – durable and resistant to fluid and dirt ingress, with no mechanical interface between mating parts these switches are suitable for a wide variety of applications, relying on being aligned, or not, to activate the required safety response.

The Safety Relay Takes Control

When any of the mechanism above is activated a safety relay will then deal with ensuring that the machinery and processes being monitored react in the manner required by the safety procedures in place. Be that allowing the machinery to operate safely in the knowledge that the operator is where they should be or by bringing the processes to a controlled and failsafe stop before allowing anyone to access to the protection zones.

There are risks in most industries and businesses, however slight, and in today’s modern world it’s a priority for any venture to ensure employees, customers and their environments are kept safe, as well as protecting valuable business assets from avoidable damage.

The costs of machinery downtime due to failures that could have been prevented are self-evident, as are the cost of litigation should an employee or member of the public become injured. It’s a simple mantra – if a risk can be reduced or eliminated, then it should be controlled or removed entirely…common sense really.

Kempston Controls, as one of the leading distributors of industrial control products, stocks an impressive range of all the safety relays and associated interlocks, switches, light curtains and ancillary components from leading suppliers such as Allen Bradley Guardmaster, SICK, Siemens, Schmersal, Omron, Pizzato and many more. Everything you will need to create your own safety relay monitored machine guarding installation, all in one place.

Call us on +44 (0) 1933 411411 or email

Schmersal SLC/SLG 440 IP69K Light Curtains – Dependability in the Extreme

Light curtains can be found in many industrial and commercials applications, from protecting employees from injury by monitoring their position to helping to maintain traffic flow in a car park. Schmersal has developed a new type of light curtain product, one that is extremely tough and durable yet is perfectly suited for hygiene sensitive areas such as pharmaceutical, food & beverage industries and anywhere where dirt and liquid ingress could damage a standard light curtain solution.

Food Safe and Industrial Applications

The new SLC/SLG 440 IP69K has been designed to withstand the rigours of life within industries that demand that their sensory solution is either food safe or as hardwearing as possible and perhaps both. Constructed with V4A Stainless steel end caps, advanced sealing technology and impact resistant transparent polycarbonate protection tubes surrounding the light curtain. These environmental countermeasures ensure that not only are these light curtains designed to withstand daily exposure to high-pressure steam, foam, hot steam, alkali solutions and high-pressure jets but they can also withstand serious impact too. And at only 50mm in diameter, they are suitable for areas where a compact safety light curtain is essential.

Some of the SLC/SLG 440 IP69k Light Curtain Features:

  • Protected against high-pressure water ingress, alkali, steam, Impact and shock resistant, food safe, IP69k Rated
  • Operating modes: Protective mode/automatic, restart interlock (manual reset)
  • Functions: Contactor control, Blanking objects, Muting, Cyclic function, Beam Coding, Double confirmation/reset, Setting mode
  • LED illuminated endcap indicates status and an integrated 7-segment display shows error codes and flashing signals to report faults and problems
  • Operating voltage 24 V DC ± 10%, Switching capacity OSSD 500mA
  • Standard Compliance:  ISO 13849-1, EN62061

Exceeding Expectations

These Active Opto-electronic Protection Devices (AOPD) have been created to meet and exceed the very stringent standards demanded by many modern industrial environments. The robust designed ensures that should they be struck by cleaning lances during a clean-down cycle or are hit by a pump truck, trolley or other transport media they will continue to function. The SLC/SLG 440 IP69K light curtains are designed to last with their performance and resistance to workplace abuse verified and independently tested by the world-renowned Ecolab Testing Laboratory.

Ultra-tough, these extreme environment light curtains also include a host of essential functions, such as double confirmation, contactor control and integrated beam blanking, this allows objects to be moved through the detectors protection field without triggering a stop signal. Cleverly, the SLC/SLG 440 IP69K series also features a dirt detector, whereby a visual message is displayed to alert the operator that the sensor reception signal is weakening, the operator can then take the appropriate action before the process comes to an unscheduled stop.

For when a tough industrial situation calls for a demanding light curtain solution, look no further than the Schmersal SLC/SLG 440 IP69k range.

For all of your light curtain and sensory protection needs call Kempston Controls on +44(0) 1933 411411, or email