Detection & Measurement System News

NEW "Best in Class" 1,082' Path Length Open Path IR Hydrocarbon Detector from Honeywell

The Searchline Excel Plus and Edge from Honeywell

Honeywell is launching the new Searchline Excel Plus/Edge infrared hydrocarbon detector on September 1st, 2021, which is a VERY significant performance evolution for open path infrared hydrocarbon detectors in the gas detection industry. 

Here is the Detection & Measurement Systems President, Mark Dundas, on this latest iteration of the already amazing technology and what excites him about it.

First, some background:

What is Open Path Infrared gas detection technology?

This technology uses an Infrared Light Source that shoots an infrared light beam across an extended distance to an Infrared Receiver that detects hydrocarbon gas clouds that cross the infrared beam. Not only is the gas detected, but the gas volume present in the cloud is measured as well.

Can you tell us a little about the history of Honeywell open path hydrocarbon detectors and why they were created?

Honeywell (at the time, Zellweger Analytics) launched the original "Searchline" open path IR hydrocarbon detector back in 1992, and it was developed in partnership with Shell Oil in the North Sea. Shell Oil didn't trust their traditional electrocatalytic combustible gas detectors on offshore production platforms because strong winds, frequently reaching upwards of 30+ knots, could rapidly dilute gas concentrations during a release before the release could be detected by their electrocatalytic LEL detectors.

When a hydrocarbon gas cloud hits the atmosphere, it immediately starts to expand. As it expands, it dilutes rapidly into lower and lower concentrations, which can make detection extremely difficult. So, gas dilution as it travels is not just a concern during windy conditions.

An additional concern was that a gas release could easily travel between their point combustible gas detectors, preventing detection as point gas detectors (whether they're electrocatalytic or point infrared hydrocarbon detectors) can only detect combustible gases that enter the gas sensor. By shooting a continuous infrared beam across an area of several hundred feet (up to 1,082' for the Honeywell Searchline Excel Edge), and with the gas cloud producing an identical response at any point along the infrared beam, the probability of the gas detector seeing the gas release is improved astronomically, compared to the performance of point gas detectors. 

Because open path hydrocarbon detectors detect and measure the total gas volume present in the infrared beam, this technology allows for rapid and reliable detection of gas clouds that travel through the infrared beam, even though the gas concentration has diluted considerably. These benefits were the vision of Shell Oil for their North Sea Production Platforms and in 1992 the Searchline was born.

What's superior about the new Searchline Excel Edge/Plus compared to the previous version?

For starters, the new Searchline Excel Plus and Edge are much easier to assemble and install than the Searchline Excel that these products have replaced. The previous version came in a kit of about 20 pieces that required considerable assembly. If you lose a single allen screw, the detector commissioning will be delayed until that item is replaced and fitted. The new Searchline Excel Plus and Edge come in only 6 pieces: the (2) stainless steel mounting plates, the IR Source and IR Receiver, and (2) Sun Shades. The new mounting plates are supplied pre-assembled, speeding up installation and providing far better ease of access for alignment.

Another advancement is the greatly improved xenon flash lamp optic assembly, which produces an extremely powerful infrared light beam (more intense than IR light produced by sunlight at any point on Earth, yet "eye safe"). This not only cuts through the thick fog and steam but it also prevents sunlight from interfering with the beam. At no point, can this receiver be "fooled" by sunlight or any other light source at your facility. Algorithms in the IR Receiver microprocessor look for a 1 Hz pulse rate and the unique "fingerprint" of the pulsed infrared light beam that is produced by the Searchline Excel Plus and Edge IR Source, ensuring that no other light sources in your facility can interfere with the open path hydrocarbon detector. 

The IR light source and receiver optics have improved so much that the maximum operating distance has taken a giant leap from the previous 650 maximum operating distance to a new maximum of 1,082 feet. The closest competitor on the market is limited to a maximum distance of 650 feet. That says a lot about the huge performance gain of the Searchline Excel Plus and Edge optics design at providing greatly increased protection against interference from fog, rain, and steam.

Which applications can benefit most from Searchline Excel Plus and Edge?

Coastal areas would especially benefit from this product. These are areas where you can expect more frequent foggy conditions, which also tend to produce thicker fog. The Searchline Excel Plus and Edge simply offer the very best performance in keeping your open path hydrocarbon detectors online during these conditions, as they're much less susceptible to blockage or interference than any other product on the market, whether they're NDIR or Laser-based, and their rugged 316 stainless steel construction protects them from corrosive elements. This adds up to greater reliability and, therefore, greater safety.

Another application for where the Searchline Excel Plus and Edge would be most useful is at salt dome storage facilities. These facilities have one or more brine ponds that are required by the Texas Railroad Commission to be monitored by hydrocarbon gas detectors. The use of open path infrared hydrocarbon detectors for this application is very typical, as these brine ponds can be 600' in length or longer. The extended maximum operating distance of the Searchline Excel Edge (up to 1,082') ensures that each length of the brine pond can be monitored with a single open path hydrocarbon detector. 

Additionally, because these facilities are typically in large open areas with very little, if any hot process equipment, the presence of thick fog is not uncommon and is a real obstacle for reliable open path gas detection (fog is less of an issue in areas with hot process equipment). This is a shining example of where the advanced optics and high-intensity IR beam of the Searchline Excel Plus and Edge play a huge role in improved reliability and availability of the open path hydrocarbon detectors at these facilities.

Sum up in 5 points what excites you about Searchline Excel Plus and Edge.

Expanded operating distance to 1082 feet. Especially great for perimeter fence line monitoring. With competitive brands, you'd have to install 2 or 3 sets of open path detectors to get the coverage of one Honeywell Searchline Excel Edge.

Simplicity of design means far less complicated assembly. The mounting bracket comes fully assembled, with only one bolt required to install the IR Source or IR Receiver. It's compact and simple and can accommodate mounting to a wide variety of mounting posts, I-beams, and flat surfaces..

Large improvements to the optics design allow Searchline Excel Plus and Edge to thrive in the harshest outdoor hazardous area environments, significantly outperforming every other open path hydrocarbon detector on the market at battling fog, rain, and steam.

LED Light Ring for at-a-glance visual status communication. The IR receiver features a unique bright LED Light Ring that changes color depending on its status. 

   Green = Normal. Red = Alarm, Yellow = Fault, Orange = Inhibit, Blue = Bluetooth Connected. 

   The IR Source has a green LED Light Ring to confirm that power is supplied. These are easy to see at great distances, keeping everyone aware of potential hazards or of a product or site issue that requires attention.

Bluetooth connection to Android Tablet. Using the Honeywell app, you can access detectors within 30 feet to configure, commission, troubleshoot, test, and generate a variety of automated detailed reports. When you connect with an IR Receiver, its LED Light Ring flashes blue, followed by steady blue once Bluetooth communication has been established. There is no more simple, clear, intuitive, and informative communication interface for an open path hydrocarbon detector on the market.

Describe the Honeywell/DMS partnership

With my 40 plus years of exclusively selling and supporting Honeywell gas and flame detection products, along with DMS being their largest stocking distributor in North America, we're given every opportunity to share our thoughts and ideas with Honeywell for how their future products can be better, which is valuable privilege and opportunity that we take full advantage of. 

Honeywell provides many of our customers this same opportunity to educate Honeywell about the needs of the market at the earliest stage of product development. A lot of companies have smart guys locked away in a lab who think they're designing the best product since sliced bread. But...if they never bother to ask the customers about their applications and the features they would like to see in future products, they often end up designing products that completely miss the mark at producing the product solution that customers are actually looking for.

Honeywell designs and builds products that the market needs, because they design products based on what their customers need. We cherish being a part of that process and the Searchline Excel Plus and Edge open path IR hydrocarbon detectors are outstanding examples of the reward that comes from that effort. 

Got any questions about the Searchline Excel Plus and Edge? Talk with DMS about Honeywell gas and flame detection products. We really are experts on these products and their applications. 

We're always happy to offer our help with free telephone technical support, a free site visit to provide training and support or an on-site product demo for your next gas or flame detection requirement. You simply won't find a more knowledgeable, experienced team who can help you check this box so you can move on to your next project.

For a presentation, brochures, or more information, please email This email address is being protected from spambots. You need JavaScript enabled to view it. or schedule a call with one of our Account Managers today.

Register now for our upcoming webinar to learn more, presented by Mark Dundas.

Download the Searchline Excel Plus Brochure here.  Email us for more information.  

Watch the Honeywell Searchline Excel Plus & Edge video from our DMS YouTube Page here.

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