SMA STRING-MONITOR SSM-U-2410 Technical Information page 2

1 Overview of Product Details
1 Overview of Product Details
Product Description
• The SMA String-Monitor is a PV array junction box for outdoor areas to which several strings can be connected in
parallel. The SMA String-Monitor collects, measures and monitors the input currents of the strings, assists in
detecting failures, thus helping to minimize power and yield losses.
• The measured values are transmitted from the SMA String-Monitor via Ethernet to the next SMA String-Monitor in
the communication bus up to the inverter. Distances of up to 100 m between the nodes are possible when using
copper cables. Greater distances of up to 2,000 m between two nodes are possible via optical fibers (see
Section 8, page 24).
• The number of SMA String-Monitors connectable to an inverter depends on the DC inputs of the inverter. One
SMA String-Monitor per DC input can be connected to the inverter.
• Up to ten SMA String-Monitors can be connected in line topology to each string monitoring communication
terminal of the inverter (for information on the number of string monitoring communication terminals, see the
inverter manual).
• The SMA String-Monitor is equipped with a DC load-break switch. The DC load-break switch can disconnect the
PV array connected to the SMA String-Monitor from the inverter.
• The SMA String-Monitor may only be operated if the strings are protected with fuses. SMA Solar Technology AG
guarantees the safe operation of the SMA String-Monitors in combination with inline fuse connectors as string
fuses and when the inline fuse connectors are connected directly to the DC connectors of the string cables of the
SMA String-Monitor. Using a different type and location of fuses for the strings does not guarantee the safe
operation of the SMA String-Monitor and the observance of the thresholds by SMA Solar Technology AG. The
inline fuse connectors are available as an accessory (see Section 8, page 24).
• There are six SMA String-Monitor models available depending on the system voltage and on the number of PV
inputs to be monitored:
– The SSM-U-XX10 is suitable for voltages of up to 1,000 V
inputs.
– The SSM-U-XX15 is suitable for voltages of up to 1,500 V
inputs.
Equipment and Equipment Options
• Depending on the product option, the SMA String-Monitor is equipped with 16, 24 or 32 measuring channels.
Different numbers of string inputs and string fuses can be assigned to the measuring channels. This allows you to
achieve the optimum design for your PV system and to protect the PV array from reverse currents.
• The interior of the SMA String-Monitor is equipped with protective covers for the lower DC input area and for the
upper DC output area. This facilitates working on the disconnected lower DC input area in the SMA String-
Monitor without having to disconnect the DC output area from voltage sources on the inverter side.
• The string fuses are attached on the outside of the enclosure of the SMA String-Monitor. This prevents additional
heat in the enclosure caused by the waste heat of the string fuses.
Inline fuse connectors of the SUNCLIX plug-in system by Phoenix Contact with internal gPV fuse are available as
an accessory. The inline fuse connectors are connected to the pre-installed DC connectors of the string cables of
the SMA String-Monitor.
The inline fuse connectors can be connected to the positive and/or negative terminal of the PV inputs and are
available in different electrical current strengths.
• The SMA String‑Monitor is equipped with a type II overvoltage protection. This protects the inverter against
overvoltage. The SMA String-Monitor can be additionally equipped with a type II overvoltage protection for the
communication connection and for the 230 V
2 SSMUXX1015-TI-en-10
and is available with XX = 16, 24 or 32 PV
DC
and is available with XX= 16, 24 or 32 PV
DC
voltage supply of the SMA String-Monitor.
AC
SMA Solar Technology AG
Technical Information