Piros Light barriers - Proxitron GmbH - #1

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Thru-Beam, Retro-Reflective and Diffuse Sensors The Piros Adjusting Device 29.06.2000 Details are subject to change without notice. Proxitron GmbH - Gärtnerstr. 10 - D-25335 Elmshorn - Tel. 04121/2621-0 - Fax. 04121/24404 - mail@proxitron.de PIL001E Functioning safety of thru-beam, retro-reflective and diffuse sensors depends considerably on alignment. In case of thru-beam sensors the transmitter and the receiver must be adjusted to each other. In case of retro-reflective sensors resp. Diffuse sensors these must be aligned to the reflector resp. to the object. Moreover, retro-reflective sensors require the sensibility to be adjusted by means of the incorporated potentiometer. Thus the desired reflection by the object is inhibited in the near range. Adjustment is facilitated by means of a 2-colour LED (red/green) as well as by 2 additional green LEDs. If no IR radiation reaches the sensor, all 3 mm LEDs remain dark. Already slight transmitter radiation induces the sensor to switch. On switching the first 3 mm LED starts blinking in red. Thus following is indicated: There is radiation, however it is not sufficient for safe operation. Units with a contamination control output indicate trouble when this state of operation lasts longer than 200 ms. With increasing radiation the first LED changes from blinking in red to green. Now safe operation is guaranteed. On alignment you should try to achieve that the second and third green LED give light as well, in order to obtain optimum reserve for functioning. Adjustment is facilitated by using a swivel stand with two axles (HM 1). First align the sensor roughly until indication is effected. Stop the horizontal axle in this position and set the vertical one to max. indication. Then stop vertical axle and set horizontal one to max. indication. If required repeat this procedure until optimum adjustment is achieved. Thru-beam sensors LA_ (receiver) The receiver switches as soon as IR radiation of the transmitter arrives. Normally-close: large LED (red) gives light Normally-open: large LED (red) stops giving light By means of the electronic adjusting unit align the receiver exactly to the transmitter: When the sensor swivels, the green LEDs reach their max. indication in the center of the optic axis. ATTENTION: In case of large distances between transmitting and receiver it is not possible to get all LEDs giving light. Retro-reflective sensors LR_ Diffuse sensors LT_ The retro-reflective sensor switches as soon as IR radiation of the reflector arrives. Normally-close: large LED (red) gives light Normally-open: large LED (red) stops giving light. The diffuse sensor works without reflector. It switches as soon as IR radiation reflected by the object arrives. Normally-close: large LED (red) stops giving light Normally-open: large LED (red) gives light By means of the electronic adjusting unit align the sensor exactly. When the sensor swivels, the green LEDs reach their max. indication in the center of the optic axis. If required the approx. point of operation of retro-reflective sensors is to be determined by means of the potentiometer. The position of the potentiometer has different meanings dependent on the application: If in case of max. position of the poti (at the right) all green LEDs give light, max. protection against contamination of sensor and reflector is achieved – however in the near range of the sensor there is danger of misfunction because of possible reflection by the object itself. Therefore the point of operation is to be shifted by turning the potentiometer to the left until only the 2-colour LED gives green light. If safety in operation is not longer achieved, e. g. by contamination, the LED changes from green to red blinking. NOTE: If the sensor does not work at max. position of potentiometer (at the right), you must find out when the sensor begins working by slight turning to the left.