Abstract: A data collector having an integrated laser tachometer. The data collector includes, within a housing that can be held by a single hand, circuitry for receiving a vibration signal to be digitized, as well as an optical system for receiving light from outside said housing to be converted to a digital tachometer signal. Digital signal processing circuits within the housing receive, store or process the digitized vibration signal and/or the digital tachometer signal, for the purpose of predictive maintenance. The housing of the data collector also holds a display and input keys, so that an operator may use the same hand for holding and controlling the data collector, and for holding the integrated laser tachometer. This frees a hand for holding an accelerometer or for other purposes. Use of a data collector with an integrated laser tachometer is thus substantially more convenient than using a data collector with a separate, nonintegrated laser tachometer attachment.

Abstract: A hierarchical distributive control system is disclosed. The lowest level of the system is a stand alone controller with hot plug in capability, which can accept either analog or digital signals, scale these signal with input subroutines, perform any one of a number of algorithms to produce control signals or can manually produce control signals and output these control signals as either analog or digital signals to field devices. A plurality of controllers communicates with an associated condenser over duel parallel digital communication buses with a full echo, verify communication routine. The condenser contains all records for all controllers under its supervision and can download control information into any replaced controller. A subhost is interconnected to a group of condensers and contains all records contained in all condensers under its supervision. All information can be uploaded from condensers to subhost or downloaded from subhost to condenser.