SMA SUNNY BOY 1700, Installation Manual

Page: 26 / 48

Installation SMA Technologie AG
Page 26 SB1700-11:SE2006 Installation Guide
PV string (DC) connection
To connect up the input, follow these steps:
1. Check that the PV generator connectors have
the right polarity and do not exceed the
maximum string voltage of 400 V (DC). See also
section 4.2 "PV generator requirements"
(page 15).
Caution! The PV-strings generate a lethal DC voltage. Be very
careful when you handle the DC connectors and the DC cables!
2. Taking one DC plug connector at a time,
measure the direct current voltage between one
DC plug connector of a string and earth
potential.
3. If the measured voltages are constant and if
their total is roughly the same as the open circuit
voltage of the string then there is a earth fault in
this string. Its approximate location can be
deduced from the relationships between the
voltages.
Do not connect strings to the Sunny Boy 1700 that contain a earth
fault until you have fixed the earth fault in the PV generator.
4. Repeat points 2 and 3 for each string.
5. Connect up the faultless PV generator strings to
the inverter.
6. Close off the unneeded DC input sockets using
the protective caps supplied in the accessories
kit.
PE
+ - + -
String 1
String 2