IV25101A_e.DOC / Feb-08
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1.
Introduction
IV251 is a small and low-cost, but highly performing converter for industrial applications, where
the information of a sensor or encoder with SSI interface needs to be converted to an analogue
signal or to a serial RS232/485 data format.
The unit has been designed as a compact module with 12 screw terminals and a 9-position
SUB-D connector (female). The housing is suitable for standard DIN rail mounting.
Applicable encoders and sensors:
Single-turn or multi-turn absolute encoders and all similar sensors using a standard SSI
interface (6 to 25 bits of resolution with binary or Gray code). The unit can operate in either
master mode (clock signal generated by the IV251 unit), or in slave mode (clock signal
generated by a remote device)
Remark to the encoder resolution:
The unit provides settings for the standard resolutions of 13 bits, 21 bits and 25 bits. In
general, for sensors with other resolutions you can use the next higher setting (i.e. set the
unit to 21 bits with a sensor of 16 bits).
Depending on brand and specification of the encoder, in some cases it may be necessary to
blank out the surplus bits by using the bit blanking function described later. In general
however, the unit should work perfectly also without special bit blanking.
