SMA SB 3000TL - Manual (Page 45)

10 Disconnecting the Inverter from Voltage Sources
Prior to performing any work on the inverter, always disconnect it from all voltage sources as
described in this section. Always adhere to the prescribed sequence.
Destruction of the measuring device due to overvoltage
• Only use measuring devices with a DC input voltage range of 1,000 V or higher.
Procedure:
1. Disconnect the circuit breaker and secure it against reconnection.
2. If an additional DC load-break switch is available, switch off the DC load-break switch and
secure against re-connection.
3. If an ESS is plugged in, remove the ESS.
4. If the multifunction relay is used, switch off any supply voltage to the load.
5. Wait until the LEDs, the display and if necessary, the load connected to the multifunction relay,
are switched off.
6. Use a current clamp to ensure that no current is present in the DC cables.
7. Remove all screws of the lower enclosure lid using an Allen key (AF 3) and remove the
enclosure lid.
8. Release and remove all DC connectors. Insert a
slotted screwdriver or an angled screwdriver
(blade width 3.5 mm) into one of the slide slots
and pull the DC connectors out downwards. Do
not pull on the cable.
9. Ensure that no voltage is present at the DC inputs of the inverter.
10. Use a suitable measuring device to check that no voltage is present at the AC connecting
terminal plate between L and N and L and PE. Insert the test probe (maximum diameter:
2 mm) in each round opening of the terminal.
11. Flip the display up to have more space to make the measurement. Loosen the screw on the
display.
☑ The display clicks into place.
12. Ensure that no voltage is present between any terminal of the multifunction relay and PE of the
AC connecting terminal plate.
10 Disconnecting the Inverter from Voltage Sources SMA Solar Technology AG
Operating Manual 45 SB30-50TL-21-BE-en-11