991-06-70-01-00 is a two-wire, loop-powered transmitter for axial-position measurement on compatible rotating machinery. The 06 option defines a 0.6–0–0.6 mm full-scale range and the output is proportional to shaft axial position rather than mechanical thrust force.
991-06-70-01-00 accepts a matched 3300 NSv probe and extension-cable chain with a 7.0 m total system length, then provides a 4–20 mA signal to the connected control system. It should not be mixed with 3300 XL probe families by connector appearance alone.
991-06-70-01-00 uses 35 mm DIN-rail clips and the 00 No Approvals option. The 991 provides a simple transmitter interface, but Baker Hughes states that it does not replace the functions of a complete continuous machinery-protection system.