SMA SB 4200TL Multi-String Installation - Manual (Page 23)

SMA Technologie AG Installation
Installation Guide SB4200TL-13:SE2006 Page 23
PV String (DC) Connection
Connect the PV strings as follows:
1. Check the PV generator connections on their
correct polarity and compliance with the maxi-
mum string voltage of 750 V DC, see chapter
4.2 „Requirements: PV-Modules” (page 15).
The voltage from the strings is very dangerous! Be very careful
and pay attention to all applicable safety regulations!
2. Measure the DC voltages between each PV plug
connector of a string and ground potential. Fol-
low the safety instructions!
3. If the measured voltages are constant and their
total approximately corresponds to the open-cir-
cuit voltage of the string, a ground fault has oc-
cured in this string. The ratios of voltages
approximately indicate where the ground fault
can be found.
When you have found a ground fault in a string, only connect it to
the Sunny Boy 4200TL Multi-String after you have removed the
cause for the ground fault in the PV generator.
4. Repeat steps 2 and 3 for the other string.
5. Connect the trouble-free PV strings to the Sunny
Boy 4200TL Multi-String. Make sure to connect
them with correct polarization.
6. Close off the unneeded DC input sockets using
the protective caps supplied in the accessories
kit.
When connecting the plus and minus
poles of a string make sure to choose
the correct connection!
PE
+ - + -
String A String B