POSITAL’s IXARC programmable incremental rotary encoders can now be configured to deliver fractional pulse rates (fractional PPR). The device can be programmed to transmit a single pulse for more than one shaft revolution (for example, a PPR of 0.125 would correspond to one signal pulse for eight shaft rotations). They can also be set up to deliver pulse rates that are not even multiples of the number rotations (a PPR of 3.5 would correspond to seven pulses for two rotations).
Fractional pulse rate encoders are often used in conveyor and web applications to simplify control system setup.
Systems requiring fractional PPR have traditionally made use of special optical encoders, such as the Photocraft’s HS20-P and RS-P encoders with the .125AJ option. POSITAL now offers its rugged IXARC magnetic encoders as a compatible alternative to this older technology. POSITAL’s IXARC encoders make use of magnetic sensing and are available with IP66/67 rated environmental protection, making them much less susceptible to moisture or dust than their optical counterparts. They are also more mechanically robust, with high shock and vibration resistance. With a wide variety of mechanical options available, including shaft type and diameter, flange and casing types, materials and level of environmental protection, IXARC encoders can fit into almost any system.
A special feature of these encoders is their programmability. Key performance characteristics can be selected by setting software parameters without mechanical changes. Fractional pulse rates can be set anywhere from 0.125 PPR to 8 PPR in steps of 0.125 PPR. (Integer pulse rates as high as 16,384 PPR can also be selected.) Communications interfaces are programmable, with push-pull (HTL) or RS422 (TTL) outputs available. Connector pin-outs can be arranged to match other products, such as the Photocraft units. While IXARC encoders would normally be ordered with the required performance parameters preset at the factory, they can be re-configured on-site using POSITAL’s convenient UBIFAST programming tool. This versatility makes IXARC programmable encoders an ideal choice for component replacement in existing systems or for new projects.
