Replacement of the power supply module must be carried out by trained personnel, and the power supply voltage must be turned off while the work is being performed.

In general, the electronic components of the MiCOM P30 family of devices are designed for a long service life.

For the power supply, however, dimensioning requirements dictate the use of electrolytic capacitors that are subject to increased wear and tear. The useful life of these capacitors depends on their temperature and thus on the components fitted in the device, the load conditions, device location and environmental conditions.

The internal voltage levels are cyclically checked by the P30 self-monitoring functions. In case the voltage levels deviate from their specified values a warning message will be issued or, for persistent problems, the device will be set to a safe condition (blocking). Hence, there is no imperative need to replace the power supply module after a pre-defined period of time. However, should you need to guarantee a high availability of the device then we recommend preventive replacement of the power supply module after a period of 8 to 10 years.

Moreover, the power supply module of the P632 is equipped with a lithium battery for non-volatile storage of fault data and for keeping the internal clock running in the event of failure of the auxiliary power supply. The useful life of the lithium battery depends on the auxiliary power supply of the device.

During normal operation, the battery voltage is monitored. If the voltage falls below a pre-defined threshold, a warning message will be issued and the battery has to be replaced.

After the maintenance procedures described above have been completed, new commissioning tests as described in Chapter “Commissioning Tests” must be carried out.