Manual Energy Storage Inverter ESI-S
The ESI-Manager user interface 123
Table 47: Possible error messages during automatic CT identification
ESI-Manager error messages during automatic CT identification
The CT identification found inconsistent CT positions.
The CT identification did not end within an appropriate time frame.
The CT identification required an abnormally high DC voltage.
The most common causes for these messages are:
•
CTs not connected or shorted
•
CTs connected in open loop configuration
•
Usage of an excessive CT ratio (including summation CTs). The CT ratio limit
is set at 20000/5.
−
After acknowledging the error message, the CT values existing before the start
of the process will be restored and the automatic CT detection procedure will be
ended. The unsuccessful CT detection attempt is recorded in the event logging
window.
Conditions under which the automatic CT identification process may give unsatisfactory
results include:
−
The use of CTs with extremely high ratio’s (> 20000/5). This will result in an error
message indicating inconsistent CT positions. In this, the ratio of the summation
CTs that may be present should be included.
−
The presence of a low impedance directly downstream of the inverter connection
although the CTs have been correctly installed upstream of the inverter
connection. This will result in wrong CT ratio’s being found. In that case the
commissioning engineer can easily correct the CT ratio’s found.
−
The use of complex CT arrangements including summing CTs.
It is recommended that the results obtained with the automatic CT detection
procedure be crosschecked with a visual inspection of the installation.
7.9.3.3.2 Manual set up of the CT positions and ratio’s
