Insulation Monitor/Interruption, Insulation Monitoring - Fronius Symo Advanced Mode D'emploi

Insulation Mon- The inverter is equipped with the following safety features as required by UL
itor/Interrup-
1741 and the National Electrical Code:
tion, Insulation
Monitoring Insulation monitor (IMI/RCMU)
The IMI (isolation monitor interruptor) feature is performed by the RCMU (resid-
ual current monitoring unit) feature in the inverter. This feature automatically
monitors whether a leakage current exists in the grid power feed operation. The
inverter is disconnected from the grid if a defined leakage current is exceeded.
NOTE!
Automatic reconnection no longer occurs after the device is disconnected from
the grid five times as a result of exceeding the defined leakage current value.
The State Code 607 shown on the display must be acknowledged to reconnect.
Insulation monitoring of ungrounded solar modules
In the case of grid connected photovoltaic systems with ungrounded solar mod-
ules, the inverter checks the insulation resistance between the positive and neg-
ative pole in relation to the earth potential before energy is fed into the grid. The
inverter issues a state code if the insulation resistance is too low. The inverter is
therefore not permitted to start feeding energy into the grid.
Arc detection/
The inverter is equipped with integrated arc detection/interruption, which de-
interruption tects and extinguishes serial arcs.
For example, a serial arc can occur after the following errors or situations:
-
-
-
-
If a serial arc is detected, the power is switched off and the grid power feed oper-
ation is interrupted. A state code is shown on the display. The state code on the
display must be manually reset before the grid power feed operation can be re-
sumed.
The power shutdown also extinguishes the serial arc.
NOTE!
This product is equipped with a communication interface in line with the "Com-
munication Signal for Rapid Shutdown - SunSpec Interoperability Specifica-
tion".
Power optimizers and other MLPE features in the photovoltaic system can impair
the correct functioning of the arc detection/interruption. When using these kinds
of components, the system installer is responsible for ensuring the correct func-
tioning of the arc detection/interruption. Contact your Fronius Technical Sup-
port for more information.
10
Poorly-connected plug connections on the solar module
Poor or defective cable connections on the solar module side, which enable a
connection against the earth potential
Defective solar modules due to problems in the junction box or production
errors, such as high resistance solder connections in individual solar cells
Cables incorrectly connected to an inverter's input terminals