DS-11

Function of the DS-11 selsyn sensor

The main function of the DS-11 sensor is angular position transmission without sliding electrical contacts. When AC excitation voltage is applied to the excitation winding, the sensor generates output voltages whose amplitudes depend on the rotor position relative to the stator. These signals are used to determine angular mismatch and to transmit the measured angle to a position indicator, control circuit or follow-up system. The contactless design helps reduce friction, sparking and wear, which is important in gyroscopic instruments and precision aircraft automation.

DS-11 modifications and design variants

The DS-11 series includes several letter modifications: DS-11A, DS-11B, DS-11V and DS-11G. These versions are associated with TU 6Zh2.329.014 technical conditions. The exact modification is important because the mechanical configuration and mounting method may differ. The source context notes that DS-11G is installed directly on the gyro precession axis, with the rotor mounted on the gyro shaft and the stator placed in the gyro frame bore. This arrangement removes separate bearing shields from the sensor and minimizes mechanical influence on the gyro unit.

Operating principle of DS-11

DS-11 operates in transformer mode. The unit includes an excitation winding and secondary windings arranged to form an angular signal. In a typical selsyn configuration, one primary excitation winding and three stator windings shifted by 120 degrees are used. Some versions may operate as sine-cosine rotary transformers with two windings shifted by 90 degrees. As the rotor turns, the induced voltages in the secondary windings change in amplitude. The receiving system compares these voltages and determines the angular position of the connected shaft or gyro frame.

Application of DS-11 on Mi-8 / Mi-171 equipment

DS-11 sensors are used in aircraft systems where angular movement must be measured and transmitted electrically. The source context indicates use on Mi-8, Mi-8T, Mi-8MTV, Mi-171 and Mi-172 helicopters, depending on equipment configuration. Typical installation areas include gyroscopic instruments, attitude and heading systems, follow-up drives, automatic control circuits and test equipment. Since actual installation depends on aircraft version and installed avionics, applicability should be confirmed by the equipment catalogue and technical documentation for the specific unit.

Ordering and replacement of DS-11

When ordering a DS-11 sensor, the required letter modification must be confirmed first. DS-11A, DS-11B, DS-11V and DS-11G may not be interchangeable without checking mounting and electrical data. The buyer should specify whether the sensor is required with bearing shields or in the bearingless configuration for direct mounting inside a gyro mechanism. It is also important to confirm condition category, passport availability, storage records, test status and whether the sensor is required for onboard installation or ground test equipment.