T18 Sensors DC-Voltage Series Self-Contained DC-Operated Sensors Features Featuring EZ-BEAM technology to provide reliable sensing without the need for adjustments (most models) T style plastic housing with 18 mm threaded lens mount Models available in opposed, retroreflective, diffuse, and fixed-field modes Completely epoxy-encapsulated to provide superior durability, even in harsh sensing environments rated to IP69K Innovative dual-indicator system takes the guesswork out of sensor performance monitoring Advanced diagnostics to warn of marginal sensing conditions or output overload 10 to 30V dc choose SPDT (complementary) NPN or PNP outputs (150 mA max. ea.) Models Sensing Mode Model* Range LED Output T186E Opposed T18SN6R 20 m (66 ) NPN Infrared T18SP6R PNP OPPOSED 950 nm T18SN6L NPN Retroreflective with Gain control T18SP6L PNP RETRO 2 m (79 )** T18SN6LP NPN Polarized Visible Red P Retroreflective 680 nm T18SP6LP PNP POLAR RETRO T18SN6D NPN Diffuse 500 mm (20 ) with Gain control T18SP6D PNP DIFFUSE T18SN6FF25 NPN 25 mm (1 ) cutoff Infrared T18SP6FF25 PNP 880 nm T18SN6FF50 NPN Fixed-Field 50 mm (2 ) cutoff T18SP6FF50 PNP FIXED-FIELD T18SN6FF100 NPN 100 mm (4 ) cutoff T18SP6FF100 PNP * Standard 2 m (6.5 ) cable models are listed. 9 m (30 ) cable: add sufxfi W/30 (e.g., T186E W/30). 4-pin Euro-style QD models: add sufxfi Q (e.g., T186EQ). A model with a QD connector requires a mating cable. (See page 7.) ** Use polarized models when shiny objects will be sensed. WARNING . Not To Be Used for Personnel Protection Never use these products as sensing devices for personnel protection. Doing so could lead to serious injury or death. These sensors do NOT include the self-checking redundant circuitry necessary to allow their use in personnel safety applications. A sensor failure or malfunction can cause either an energized or de-energized sensor output condition. Consult your current Banner Safety Products catalog for safety products which meet OSHA, ANSI and IEC standards for personnel protection. Printed in USA 02/08 P/N 121526 rev. A T18 Sensors dc-Voltage Series Fixed-Field Mode Overview T18 Series self-contained fixed-field sensors are small, powerful, infrared diffuse mode sensors with far-limit cutoff (a type of background suppression). Their high excess gain and fixed-field technology allow them to detect objects of low reflectivity, while ignoring background Cutoff surfaces. Distance Object B Receiver Object The cutoff distance is fixed. Backgrounds and background objects must always be placed or Elements A Background beyond the cutoff distance. Lenses Near R1 Detector Fixed-Field Sensing Theory of Operation Far The T18FF compares the reflections of its emitted light beam (E) from an object back to R2 Detector the sensors two differently aimed detectors, R1 and R2 (see Figure 1). If the near detector (R1) light signal is stronger than the far detector (R2) light signal (see object A, closer than the cutoff distance), the sensor responds to the object. If the far detector (R2) light signal is E Emitter stronger than the near detector (R1) light signal (see object B, beyond the cutoff distance), the sensor ignores the object. Sensing Range The cutoff distance for model T18FF sensors is fixed at 25, 50 or 100 millimeters (1 , 2 , Object is sensed if amount of light at R1 or 4 ). Objects lying beyond the cutoff distance usually are ignored, even if they are highly is greater than the amount of light at R2 reflective. However, it is possible to falsely detect a background object, under certain conditions (see Background Reflectivity and Placement). Figure 1. Fixed-field concept In the drawings and discussion on these pages, the letters E, R1, and R2 identify how the sensors three optical elements (Emitter E, Near Detector R1, and Far Detector R2) line up across the face of the sensor. The location of these elements defines the sensing axis (see Figure 2). The sensing axis becomes important in certain situations, such as those illustrated in Figures 5 and 6. Sensor Setup Sensing Reliability For highest sensitivity, position the target object for sensing at or near the point of maximum excess gain. Excess gain curves for these products are shown on page 5. They show excess gain vs. sensing distance for sensors with 25 mm, 50 mm, and 100 mm (1 , 2 , and 4 ) cutoffs. Maximum excess gain for the 25 mm models occurs at a lens-to-object distance of Sensing Axis about 7 mm for the 50 mm models, at about 10 mm and for the 100 mm models, at about 20 mm. Sensing at or near this distance will make maximum use of each sensors available sensing power. The background must be placed beyond the cutoff distance. (Note that the reflectivity of the background surface also may affect the cutoff distance.) Following these two guidelines will improve sensing reliability. Background Reflectivity and Placement Avoid mirror-like backgrounds that produce specular reflections. False sensor response will occur if a background surface reflects the sensors light more strongly to the near detector, or As a general rule, the most reliable sensing of an object approaching from the side sensing detector (R1), than to the far detector, or cutoff detector (R2). The result is a false occurs when the line of approach is parallel ON condition (Figure 3). To cure this problem, use a diffusely reflective (matte) background, to the sensing axis. or angle either the sensor or the background (in any plane) so the background does not reflect light back to the sensor (see Figure 4). Position the background as far beyond the cutoff Figure 2. Fixed-field sensing axis distance as possible. An object beyond the cutoff distance, either stationary (and when positioned as shown in Figure 5), or moving past the face of the sensor in a direction perpendicular to the sensing axis, can cause unwanted sensor triggering if more light is reflected to the near detector than to the far detector. The problem is easily remedied by rotating the sensor 90 (Figure 6). Banner Engineering Corp. Minneapolis, MN U.S.A www.bannerengineering.com Tel: 763.544.3164 2 P/N 121526 rev. A R1 R2 E