Heidenhain (Schaumburg, IL) expanded its ERA 4000 series of angle encoders with the ERA 4×80, 4×81, and 4×82 versions. The ERA 4x80 is mounted using a centering collar method, with a low profile encoder system. With seven standardized diameters, system accuracies are offered with the 20 μm grating period version from ±6.1 arc seconds with the smallest diameter to ±2.8 arc seconds on the largest.

The ERA 4×81 is a weight-reduced T profile version, mounted using the 3-point centering method. Encoder system accuracies of ±8.6 arc seconds are offered with the smallest diameter of the series using 20 μm grating periods and ±2.8 arc seconds for the largest diameter.

The ERA 4×82 uses the 3-point centering method for installation. It lacks a centering collar, and offers system accuracies from ±5.1 arc seconds to ±2 arc seconds for the largest diameter.