System, operating and application references from the source catalogue. Model-specific ratings are given in the specification table.
General planetary reducer principles
2024 actuator catalogue, p. 88
A planetary reducer reduces motor speed while increasing output torque. The exploded diagram identifies precision gears, precision planetary carrier, inner gear ring, input shaft and input flange fixing plate.
The source describes planetary gears mounted on a carrier, an output shaft, an inner gear ring and an externally driven sun gear. Driving the sun gear causes the planetary gears to rotate and revolve along the inner gear ring, transmitting motion through the carrier to the output shaft.
The number of gear sets determines the stages. The catalogue describes using two or three sets for larger transmission ratios and notes that adding stages increases gearbox length and decreases efficiency. Return clearance is the small angular displacement at the input when output is fixed and input is driven clockwise/counterclockwise under the described rated-torque test. The source's unit "fen" is one sixtieth of a degree.
Source illustration

General planetary reducer ordering code
2024 actuator catalogue, p. 89
The example code is EDT-BL-115-20-32-P2-22 K6-55-110-6-145-130-M8. Its fourteen positions describe product code, reducer type, output-flange dimension, reduction ratio, output-shaft diameter, accuracy class, motor input-shaft diameter, input key, input-shaft length, motor sub port, motor sub-port depth, motor distribution circle, input-flange size and installation holes.
Product-code options in the source are EDT (circular planetary reducer) and EDTM (square planetary reducer). Type options are A (straight tooth), AL (right angle/straight tooth), B (diagonal gear) and BL (right angle/helical gear). Accuracy options are P1 (Precision Backgap) and P2 (Standard Backgap).
The accompanying illustrations describe precision gears, integrated planetary carrier/output shaft and bearings, integrated inner gear ring/casing, balanced input shaft and input flange fixing plate.
Source illustration
