The HS35 incremental hollow-shaft encoder from Baumer Ltd., Southington, Conn., combines heavy-duty design with a precise optical scanner to provide reliable, closed-loop control with accuracies of 60 arc-sec.

The heavy-duty castings and sturdy walls add durability and stiffness. The large diameter between ABEC 5 bearings, together with a precise steel spacer ring, lets the encoder handle relatively high mechanical loads. Dual seals protect against contaminants and leaks. A powder coating prevents the housing from corroding, despite long-term exposure in harsh environments. And reinforced shaft inserts electrically isolate against shaft currents of up to 2.5 kV. The inserts also let the encoders be mounted on smaller shafts.

There are three versions of the encoder. HS35P is a programmable square-wave encoder. Resolutions range from 1 to 8,192 in increments of 1. Programming outputs include HTL and TTL. Users can program pulse per revolution, index pulse length and position, rotation direction, and output voltages. Users can also choose independent A and B counts.

HS35F is an industrial square-wave encoder with TTL, HTL, and OC (open-collector) outputs. Direct read resolution can be up to 56,000 ppr, but internal interpolation can boost that to 80,000 ppr. And signal quality is good, even at low speeds. The HS35S sine-wave encoder provides good signal quality at all speeds and prevents drive overheating while saving energy.

The encoders operate in temperatures from –40 to 212°F, and are available with shaft diameters from 0.5 to 1 in.

© 2012 Penton Media, Inc.