Specifications and Ordering Information Part Number 141612-01 Rev. A (11/07) Page 1 of 13 990 Vibration Transmitter Description The 990 Vibration Transmitter is intended primarily for the original equipment manufacturers (OEMs) of centrifugal air compressors or small pumps who prefer to provide a simple 4 to 20 mA proportional vibration signal as the input to their machinery control system. The transmitter is a 2-wire, loop-powered device that accepts input from our 3300 NSvTM proximity probe and its matching extension cable (available in 5m and 7m system length options). The transmitter conditions the signal into appropriate peak-to-peak vibration amplitude engineering units, and provides this value as a proportional 4 to 20 mA industry-standard signal as the input to the control system where machinery protection alarming and logic occurs1. The unit provides the following notable features: • Integrated Proximitor® Sensor – no external unit required • Non-isolated “PROX OUT" and "COM" terminals plus a coaxial connector to provide a dynamic vibration and gap voltage signal output for diagnostics2. • Non-interacting zero and span potentiometers under the Transmitter label for loop adjustment. • Test Input pin for quick verification of loop signal output, using a function generator as the input. • A Power-up Inhibit circuit to eliminate signal errors due to line voltage transients. • A Not OK/Signal Defeat circuit to prevent high outputs or false alarms due to a faulty proximity probe or loose connection. • DIN-rail clips or bulkhead mounting screws as standard options. • Potted construction for high humidity (up to 100% condesnsing) environments. • Compatible with 3300 NSv proximity probe to allo...
