SSI Rotary Absolute Encoders


Many Delta customers have successfully used the following absolute rotary encoders with SSI output:

H25, H25X, HS35, L18: Single-turn.
Important! Order the S3 option for SSI.

HMT25: Multi-turn. Make sure to order the number of turns as 4096. Lower numbers of turns will cause unused bits, which will confuse the Count Offset adjustment portion of RMCTools’ Scale/Offset wizard.

Delta has tested the multi-turn SSI AI25.
According to the specs, the SSI versions of the following encoders are also compatible: AC36, AD25, AD34, AD35, AD36 (not more than 31 or 32 bits total), AR62/63, AX65, AX70/71 Search for AI25

Encoder Products Company
A36S: Single and multi-turn, 8 to 14 bits per turn, 40 bits for turns, for a max of 54 bits (no kidding!) However, the RMC75 and RMC200 can only handle up to 32 bits, and the RMC150 SSI can handle only 31 bits.
These are fairly small form factor encoders, with very reasonable prices!
Important! Order the P2 option for SSI.

Leine Linde
Delta has tested the multi-turn ISA 608 SSI gray
According to the specs, the SSI versions of the following encoders are also compatible: 500 Robust, 600 Industrial, 900 Premium

Has some very small form factor SSI encoders. Make sure to choose an SSI encoder with the RS-422 interface.
For example: 2RMHF-SSI: Single- or multi-turn

Sick Stegmann
AFS60: Single-turn
AFM60: Multi-turn

If you will be using the encoder on a rotary axis, specify the resolution as a power of 2 *(e.g. 4096, 8192, 32,768).

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linear rotary encoder
linear rotary encoder

What is the “S3 Option”. Says to consult the factory.


It appears the S3 simply means SSI. The reference to note 3 seems to apply to all the Voltage/Output options. Then note 3 itself doesn’t mention anything about SSI.