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Aries encoder output - Quadrature or SSI?

The Aries servo drive is a very versatile drive. It is able to read encoders or resolvers, and output a simulated "differential quadrature encoder signal" from pins 3,4,5, and 6 on the Drive I/O connector (A+, A-, B+, B-, respectively).

The Aries can also read Heidenhein's EnDat (up to version 2.1) absolute encoders. In this case, instead of outputting quadrature encoder signals, the Aries outputs an SSI signal containing the encoder data. In this mode, the clock (CLK) and data (DATA) channels are again pins 3-6; CLK+, CLK-, DATA+, and DATA-, in that order, take the places of A+,A-,B+, and B-.

The Aries uses the same feedback cable (F-1A1-XX), regardless of what feedback type is being used.

The Aries SSI output specifications follow: 

SSI Clock Frequency = 1562.5 kHz

(the clock frequency can operate at lower SSI frequencies, really being determined by the clock signal coming from the controller sending the clock signals to the Aries drive)

SSI Data Format = Gray Code

SSI Data Bit Width = 31

SSI Data Bit Limit = 31


updated glh April 2013