Monitoring System Installation
& Maintenance

Major machinery trains require an API 670/671 permanent vibration monitoring system on automatic shutdown for adequate protection from catastrophic failure. Tern Technologies, Inc. personnel have the expertise to design, install and maintain such systems. As an authorized SKF Condition Monitoring sales and service representative, we market the M800A series vibration monitors. We can also service most other major monitoring system.

SKF M800A Monitor System Photo courtesy of SKF Condition Monitoring

Typically, older machines do not have vibration monitoring systems or the systems they do have are outdated. Machines built before 1970 can be retrofitted with eddy current transducers, and upgraded with modern monitoring systems which will greatly enhance their protection system.

The eddy current transducer, also called a proximity probe, is a non-contact shaft vibration measuring system that measures shaft deflection in mils (.001"). The probe cable, extension cable and driver form a tuned system calibrated together. Various probe models and drivers are not interchangeable. The eddy current probe, when properly installed, is a tool that will greatly enhance the capability of the vibration analyst to quickly locate developing problems. Older systems utilizing surface mounted transducers, such as accelerometers and velocity transducers, do not adequately detect vibration problems in heavy case machinery. This is especially true of machinery with sleeve type bearings and light rotors. Typically, on this type of machinery, by the time the transducer detects a problem, the damage has already occurred.

Installation of eddy current transducers on older equipment requires skill, ingenuity, and experience. These machines were not originally designed for installation of eddy current probes. The bearing and bearing housing must be modified for probe installation without disturbing the oil flow vibration dampening characteristics.

Installation of junction boxes, conduit, and cable runs back to the monitor should be designed for ease of maintenance for both the vibration system as well as the machine. Care must taken to insure that machinery maintenance doesn’t require removal of the conduit and junction boxes.

Tern Technologies, Inc. insures that all aspects of the installation are fully calibrated, tested, and documented. Details include: wiring schematics, loop diagrams, junction box details, parts list for each point, eddy current probe calibration curves for radial points, axial probe curves detailing position relative to active and inactive thrust bearing, bearing drawings, electrical mechanical runout documentation, and photographs showing probe installation and orientation. This will answer the inevitable question that arises when the machine starts having a vibration problem: "How was that probe installed?"

With all the steps followed, from initial design to checkout of the system, the system will be highly reliable. Management can be certain that if the machine trips due to vibration, that the trip was in fact real, and the monitoring system just saved the machine from a catastrophic failure. Just one machine saved from such a failure will easily justify the capital expenditure made to purchase and install the system.