10 Maintenance
SMA Solar Technology AG
36
MC-BOX-12-3-20-BE-en-10
Operating Manual
10 Maintenance
10.1 Inspection of Residual-Current Devices
Requirement:
If only the Multicluster Box is installed, the generator must be connected to the multicluster system and must be in
operation.
If the Multicluster Box and NA Box or Grid Connect Box are installed, the utility grid must be connected to the
multicluster system.
Procedure:
1. Stop the multicluster system at the master of the main cluster (see operating manual of the Sunny Island inverter).
2. Perform the following test on residual-current device F141 in the Multicluster Box:
• Press the [
TEST
] button.
The residual-current device trips.
✖ The residual-current device fails to trip?
• Disconnect the Multicluster Box and multicluster system (see Section 8, page 28).
• Contact the SMA Service Line (see Section 14, page 46). This will trigger the requisite spare parts order.
• If the residual-current device has tripped, wait at least five seconds.
• Reactivate the residual-current device. To do this, move the switch lever of the residual-current device into the
ON
position.
3. In der Multicluster Box check the residual-current devices
F142
,
F143
,
F144
consecutively. Use the same procedure
as described for the residual-current device
F141
.
4. Start the system at the master of the main cluster (see operating manual of Sunny Island inverter).
5. Document the test result in accordance with the locally applicable standards and directives. This will be your proof
that regular inspection has taken place.
Inspection interval for residual-current devices
The inspection interval for residual-current devices depends on the prevailing operating temperature.
• At prevailing operating temperature up to 40°C: every 6 months
• At prevailing operating temperature over 40°C: every 3 months
Instruction of end users
The test of the residual-current device is not hazardous and can be performed by the end user. If the residual-current
device does not trip, a qualified person is required to disconnect the Multicluster Box and the multicluster system from
voltage sources.
• Instruct the end user on the necessary procedure.
• Remind the end user that the inspection interval must be complied with.
• Point out to the end user that in the event of the residual-current device not tripping, a qualified person is required
to perform the next steps.
Supply of loads temporarily disconnected
During testing of the residual-current devices the connection to the utility grid is temporarily disconnected.
When grid feed-in from the generator is discontinued, the supply of the loads is also interrupted.
• If the utility grid is connected, switch off sensitive loads prior to the test.
• If only the generator is connected and in operation, proceed with the next step.
