SMA STRING-MONITOR SSM-U-2410 Technical Information page 13

SMA Solar Technology AG
5.3 Installing the DC Main Cables
You can connect up to two DC main cables per terminal by default.
The material required for the bolted connections is already pre-mounted on the busbar; further material is required
depending on the type of connection and cable. Depending on the cable cross-section, the DC main cables must be
connected to the busbars via terminal lugs or V-box terminals:
The following options are available for connecting the DC main cables:
Connecting DC Main Cables to the Busbar Using Terminal Lugs
• DC main cables 70 mm
– Aluminum cables: additionally required material: bimetal ring terminal lugs.
– Copper cables: tinned copper ring terminal lugs are pre-mounted.
Connecting DC Main Cables to the Busbar Using V-Box Terminals
• DC main cables 70 mm
Additionally required material: V-box terminals (see Section 8, page 24).
Connecting the DC Main Cables with Terminal Lugs
Cable requirements for connection with terminal lugs:
☐ Use copper or aluminum cables only.
☐ The cables must be designed for the maximum PV voltage.
☐ Maximum number of cables per potential: 2
☐ Permitted cable cross-section: 70 mm
Terminal lug requirements:
☐ Use tin-plated terminal lugs only.
☐ For the connection, only the supplied screws, washers and nuts must be used.
☐ The terminal lugs must be designed according to the temperature. Temperature: +95°C
☐ The width of the terminal lugs must exceed the washer diameter. Washer diameter: 32 mm. This will ensure that
the defined torques are effective over the whole surface.
☐ Maximum width of the terminal lugs when connecting two cables per potential: 48 mm
Connecting the DC Main Cables with V-Box Terminals
The DC main cables are connected directly to the busbars with V-box terminals. The V-box terminals are available as
an accessory.
Cable requirements for connection with V box terminals:
☐ Use copper or aluminum cables only.
☐ The cables must be designed for the maximum PV voltage.
☐ The cables must have double or reinforced insulation.
☐ Maximum number of cables per potential: 2
☐ Permitted cable cross-section: 70 mm
☐ Permitted conductor cross-section:
Cable type
Round, single-strand
Round, multi-strand
Technical Information
2 2
to 400 mm made of aluminum or copper
2 2
to 300 mm made of aluminum or copper
2
to 400 mm
2
to 300 mm
2
2
Conductor cross-section per potential
2
70 mm to 150 mm
2
70 mm to 300 mm
SSMUXX1015-TI-en-10
5 Installation
2
2
13