Connection Procedure; Connecting The Grounding Cable - SMA STRING-COMBINER DC-CMB-U15-16 Manuel D'installation

SMA Solar Technology AG

6.7.3 Connection procedure:

1. Ensure that the DC subdistribution is switched off and secured against reconnection (see Section 9 "Disconnecting and
Reconnecting").
2. Ensure that the inverter is disconnected on the DC side and secured against reconnection (see inverter manual).
3. Lead the DC main cables into the DC subdistribution through the designated enclosure opening (see Section 6) with
the appropriate seal insert (see Section 6).
4. Fit the DC main cables with tube terminal lugs. Make sure that no pieces of cable are dropped into the DC
subdistribution.
5. In the DC subdistribution, remove the fastening material for the DC main cables from the busbars.
6. Clean the contact surfaces using a clean cloth and ethanol cleaning agent. Do not touch the contact surfaces after
cleaning.
7. Clean the non tin-plated contact surfaces in the connection area with the non-woven abrasive until they have a light
metallic sheen
Additionally required material (not included in the scope of delivery):
o Ring terminal lugs (size: for M12 screw)
o Clean cloth
o Ethanol cleaning agent
Procedure:
1. Strip off the DC cable insulation.
2. Fit the DC main cables with ring terminal lugs.
3. Clean the contact surfaces using a clean cloth and ethanol cleaning agent. Do not touch the contact surfaces after
cleaning.
4. Connect the DC main cables in accordance with the circuit diagram (torque: 70 Nm). Ensure that you only use the
supplied fastening material and connect a maximum of two adjacent DC main cables to each busbar.
5. Secure the DC main cables to the cable support rail.

6.8 Connecting the Grounding Cable

In order to guarantee the function of the surge arrester, it must be connected to the external grounding.
Cable requirement:
o Conductor cross-section:16 mm
Procedure:
1. Strip 16 mm off the grounding cable insulation.
2. Connect the grounding cable to the screw terminal of the surge arrester (torque: 2.9 Nm).
3. Ensure that the grounding cable is securely clamped.
4. Ground the grounding cable in the vicinity of the Combiner Box, e.g. by means of a grounding electrode.
All spring washers can be used only one time. Whenever a screw connection is loosened, must be used a new spring
washer.
Installation Manual
to 35 mm .
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6 Electrical Connection
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