The FL series sensors can measure temperatures from 400 to 1200ºC, with adjustable emissivity and an ultra fast response time of just 1ms. Two optical heads are available; the LVO25 is designed for use over short distances with very small spot sizes, giving a measurement spot of Ø1.6mm at a distance of 80mm. The LVO35 optics are intended for longer distance measurements, and give an Ø11mm spot at a distance of 1m. Both of these optical heads use a manually adjustable focal distance to help provide the best possible measurement spot size at any distance. A white LED light can be shone through the lens of either sensing head showing the area being measured to help with precise alignment and focusing.
The sensing heads of the FL series sensors can operate in ambient temperatures up to 250ºC without the need for additional cooling, allowing them to be used in particularly hot areas which do not have access to air or water supplies for cooling. The head of the LVO25 has a diameter of 25mm and varies in length from 52.1mm to 63.2mm depending on the focal length required. The LVO35 head is 35mm in diameter and its length ranges from 66.6mm to 76.3mm, again depending on the focal length used. Both sensing heads are made of stainless steel and sealed to IP65 (IP54 where the fibre-optic cable enters).
The emissivity setting of the FL models can be quickly and easily changed using a simple rotary switch on the rear of the instrument. This adds extra flexibility to the FL models, allowing them to measure most materials and eliminating the need to remove them from service to configure them for new target materials.
The electronics unit for the FL series is made of stainless steel and is sealed to IP65. Its dimensions are Ø40mm by 113mm long. Mounting supports are available for both of the sensing heads, as are air-purge collars and 90º mirrors to allow the heads to be mounted at right-angles to the target. Each FL sensor is supplied with 1.5m of fibre-optic cable as standard, and up to 15m can be fitted on request.