SMA PPM-10 - Checking the Buffer Module

8 Maintenance
SMA Solar Technology AG
Installation Manual 61PPM-10-IA-en-16
8.3 Checking the buffer module
In case the supply voltage fails, the buffer module supplies the assemblies of the product with energy. With this energy
supply, the buffer module can bridge power outages of up to 2seconds. The capacitors store the energy required for
this in the buffer module. These capacitors age according to the operating and ambient conditions at the operating site
and thus lose storage capacity. This loss of storage capacity reduces the maximum buffer time of 2seconds over the
course of the operating time.
DATA MANAGER L
Power
Good
F1
Figure 25: Components for testing the buffer module
Recommended maintenance intervals:
• After 6 years have passed: check the buffer time of the buffer module every 12months.
• After 10 years have passed: replace the buffer module. Contact the Service (see Section11, page68).
Procedure:
1.
NOTICE
Yield loss due to unwanted stop of the programmable logic controller
When checking the buffer module, the control voltage of the product must be switched off temporarily. This
interruption can result in an unwanted stop of the programmable logic controller and thus of the PV power
plant. This can result in yield loss.
• Prior to disconnecting the control voltage on the product, manually stop the programmable logic controller
and the PV power plant (see user manual of the HybridController).
• After stopping the programmable logic controller and the PV power plant, wait a few minutes so that the
PV power plant can slowly reduce its output power to zero.
2. Via the user interface of the system controller in the PowerPlantManager check whether the output power of the
PV inverters equals zero. If the output power of the PV inverters does not yet equal zero, wait a few more minutes.
☑ On the buffer module the LED Power Good is glowing green. The buffer module is fully charged.
3. Turn off miniature circuit breaker F1.
☑ On the buffer module the LED Power Good is flashing. The buffer module is being discharged.
4. Wait for at least 2seconds.
5. Switch miniature circuit breaker F1 on again.
☑ On the buffer module the LED Power Good keeps flashing. The buffer module is being charged again.
☑ If the LED Power Good is flashing continuously and the assemblies of the product do not switch off, the
buffer time of the capacitors is sufficient.
☑ If the LED Power Good is not flashing continuously or if the assemblies of the product do not switch off, the
buffer time of the capacitors is no longer sufficient.
6. If the buffer time of the capacitors is no longer sufficient, replace the buffer module. Contact Service for this.