Siemens SIMATIC PCS 7 Monitoring and diagnostics of drive components, Diagnostics of drives

© Siemens AG 2011

Monitoring and diagnostics of drive components

Diagnostics of drives

Hardly any other group of products influences plant availabili- ty as much as drive engineering. Production comes to a stand- still when these products fail. Such unscheduled plant down- times cause expensive production outages, unplanned re- pairs, and frequently consequential damage.

This is the reason why all drive systems and frequency conver- ters of the SINAMICS, MASTERDRIVES and MICROMASTER ran- ges with their associated motors are integrated into the SIMATIC PCS 7 Maintenance Station. This results in the com- mon, uniform presentation of maintenance-relevant informa- tion which permits preventive and prognostic maintenance strategies.

The components report autonomously that maintenance is re- quired One example are the medium-voltage converters such as SINAMICS GM150. For instance, by means of a differential pressure procedure the degree of contamination of the dust filters is determined.

In the water-cooled version, the analog conductivity measure- ment continuously monitors operation of the ion exchanger and outputs an early-warning message when the exchange capacity decreases. The operating fans for air cooling and the pumps for water cooling are equipped with operating hour counters that recommend checking of components on re- aching a certain number of operating hours.

The CM 240NE chemistry module can be used in connection with the SINAMICS G120 Control Unit CU 240S DP-F. The che- mistry module includes a terminal strip that meets the NAMUR specifications and thus the essential requirements of the chemical industry. An ATEX-certified PTC thermistor analy- sis function for thermal motor protection via PTC thermistors built into the motor is integrated.

The drive systems are incorporated into the maintenance sta- tion using the DriveES PCS 7, an add-on package for SIMATIC PCS 7. DriveES PCS 7 allows Siemens drives to be controlled via SIMATIC PCS 7 using standard function blocks and operated and controlled in the operator station by means of faceplates.

Status assessment of high-voltage machines

An established procedure for assessing the condition of high-voltage machines is partial-discharge diagnostics (PD) which is carried out as an offline or online measurement depending on the application. This is an important measu- re within reliability-based maintenance strategies for large drives.

In order to measure the PD signals, as an option the paten- ted "SIEMENS Insulator Integrated Coupling Units" can be installed in high-voltage motors at the factory.

The post insulators in the terminal box are simply replaced by the Insulator Integrated Coupling Units. This results in decisive benefits:

■Simple, low-cost installation

■No change in terminal box necessary

■Rugged mechanical design

■Highest and tested safety of the insulation distances

■Direct interface to condition diagnostics

The CM240NE chemistry module

IEC motors The SINAMICS family

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