Monitoring Unit Makes Maintenance Plannable
One of the technological highlights KSB Aktiengesellschaft, Frankenthal, plans to present at its ACHEMA booth is a monitoring unit developed by joint venture partner Nikkiso. The E-Monitor specially developed for use on canned motors monitors the axial and radial plain bearing status and continuously indicates any changes in the bearings’ condition.
At this year’s ACHEMA, KSB will present the “E-Monitor” (Nikkiso-KSB), the monitoring unit developed by joint venture partner Nikkiso.
Provided the bearings are operated properly in continuous mode, they often give reliable service for 8 to 10 years. The monitoring unit allows operators to predict when it is time for the next maintenance round. Costly can and winding damage as well as unplanned downtimes are thus avoided. Service teams benefit greatly from the fact that maintenance becomes plannable.
The monitoring unit receives data from eight sensors mounted in the stator space of the motor. They monitor the rotor position on the basis of the rotor s magnetic field. As soon as the rotor moves away from its desired position, the measuring probes will detect the change. After digital processing of the status change signals, the unit shows the operator the condition of the pump bearings on a “traffic light” display. Green LEDs signal that everything is ok with the bearings. An amber LED warns the operator that the pump should be checked during the next regular plant downtime. If the red LED lights up, the operator knows that the pump should be taken out of service and checked as soon as possible. The unit can be integrated in a process control system by means of a “0 to 5 V DC” or “4 to 20 mA“ signalling circuit.
Added functions, such as a direction-of-rotation indicator, show whether the pump is running in the wrong direction, which eliminates the need for phase rotation measure¬ments during commissioning. The operation indicator showing whether the pump is running can be very helpful in a noisy environment, because canned motor pumps are extremely quiet. As the E-Monitor is supplied with power from the motor’s terminal box, there is no need for external cabling, which keeps costs to a minimum. The unit is supplied with the pump and fully configured, and is ready for operation as soon as the pump has been commissioned.
To date, Nikkiso has supplied more than 30,000 E-Monitor units around the world. At ACHEMA in Frankfurt, Nikkiso-KSB will have a functional model on display which gives visitors an opportunity to test the unit by simulating unacceptable operating conditions.
Source: KSB SE & Co. KGaA
