SMA SC 500CP-US-10 600V - Manual (Page 74)

9 Grid Monitoring SMA America, LLC
74 SCCP-US-BE-US_en-52 Operating Manual
If the power frequency falls below the value defined in the parameters HzCtllLim or HzCtlllLim, the inverter waits for the
period defined in the parameters HzCtllLimTm and HzCtlllLimTm and disconnects from the utility grid.
If the power frequency increases above the value defined in the parameter HzCtlhLim, the inverter waits for the period
defined in the parameter HzCtlhLimTm and disconnects from the utility grid.
Figure 36: Parameters for monitoring the power frequency
9.4 Measurement Accuracy
The inverter is not equipped with a calibrated meter. The display values may deviate from the actual values and must not
be used as a basis for invoicing. The inverter’s measured values are required for the system management and to control
the current to be fed to the grid.
Example: Behavior of the inverter in the event of underfrequency
The first limiting value for the underfrequency is defined in the parameter HzCtllLim and amounts to 59.3 Hz.
The associated period is set to 160 ms in the parameter HzCtllLimTm. The second limiting value for the underfrequency
is defined in the parameter HzCtlllLim and is 57 Hz. The associated period is set to 160 ms in the parameter
VCtlllLimTm.
The power frequency falls to 59 Hz and has therefore fallen below the first underfrequency limiting value.
The inverter waits 160 ms. If the power frequency does not increase above the first limiting value within this period, the
inverter disconnects from the utility grid.
Parameter Explanation Default 60 Hz value
[50 Hz value]
HzCtllLim The first threshold of the underfrequency 59.3 Hz [49.3 Hz]
HzCtllLimTm Time period for the first limiting value of the underfrequency 160 ms [200 ms]
HzCtlllLim The second threshold of the underfrequency 57 Hz [47 Hz]
HzCtlllLimTm Time period for the second limiting value of the underfrequency 160 ms [200 ms]
HzCtlhLim Limiting value for the overfrequency 60.5 Hz [50.5 Hz]
HzCtlhLimTm Time period for the threshold of the overfrequency 160 ms [200 ms]