SMA NR-PL-DCEMV41-01, Manual, Page: 14 / 304

6 Replacing the DC EMV Assembly SMA Solar Technology AG
Replacement Manual STP50-DC-EMV-DST-RM-xx-10 14
12. Ensure that no voltage is present at the DC inputs on
the inverter using a suitable measuring device.
A
B
C
<30V
13. Unscrew (TX25) all ten screws of the enclosure lid of
the AC-Connection Unit and remove the enclosure
lid carefully towards the front.
10x
14. Set the screws and the enclosure lid aside and store safely.
15. Ensure there is no voltage on the AC terminal block between L1 and N, L2 and N, and L3 and
N using a suitable measuring device. To do so, insert the test probe (maximum diameter:
2.5 mm (0.078 in)) into the measuring points of the respective terminal blocks.
16. Ensure that there is no voltage on the AC terminal block between L1 and grounding
conductor, L2 and grounding conductor, and L3 and grounding conductor using a suitable
measuring device. To do so, insert the test probe (maximum diameter: 2.5 mm (0.078 in)) into
the measuring points of the respective terminal blocks.
6 Replacing the DC EMV Assembly
6.1 Removing the DC EMV Assembly
NOTICE
Damage in the inverter due to incorrect removal of assemblies
There are several assemblies mounted one behind the next in the inverter. Bulky components are
mounted on the rear of some assemblies. When removing an assembly, the assembly behind this
can be damaged due to incorrect removal.
• Remove assemblies that have been disconnected to the front to avoid contact between the
assemblies.
Procedure:
1. Disconnect the inverter from all voltage sources (see Section 5, page 12).
2. Wait 5 minutes. This will ensure that the capacitors are discharged.
3. Remove the enclosure lid of the DC-Power Unit (TX25) by pulling it towards the front.
4. Discharge the DC EMC assembly at the contact points using a voltage detector without
intrinsic voltage source. Ensure that the residual voltage is less than 5 V.
ENGLISH