Ac Connection; Safety During Ac Connection; Connecting Ac Cables; Cable And Terminal Lug Requirements - SMA SUNNY CENTRAL 500CP XT Installation Manual

11 AC Connection

11 AC Connection

11.1 Safety during AC Connection

Danger to life from electric shock due to live voltage
High voltages are present in the live components of the low-voltage and medium-voltage grids. Touching live
components results in death or serious injury due to electric shock.
• When working in a high contact-risk environment, wear personal protective equipment.
• Do not touch any live components.
• Follow the instructions precisely.
• Observe all warning messages on the product and in the documentation.
• Observe all locally applicable safety regulations for working on the low-voltage grid and medium-voltage grid.
• Provided live voltage is not absolutely necessary, always disconnect the following components from voltage
sources before performing any work on the inverter:
– Line voltage for grid feed-in
– Internal power supply
– DC voltage from the PV array
– Additional external voltages, e.g. control signals from a control room
• Ensure that no disconnected components can be reconnected.
• After disconnecting the Sunny Central from voltage sources, wait at least 15 minutes for the capacitors of the
Sunny Central to discharge completely.
• Before working on the Sunny Central, check that all devices are completely voltage-free.
• Ground and short-circuit.
• Cover or isolate any adjacent live components.
Risk of fire due to failure to observe torque specifications on live bolted connections
Failure to follow the specified torques reduces the ampacity of live bolted connections so that the contact resistances
increase. This can cause components to overheat and catch fire.
• Ensure that live bolted connections are always tightened with the exact torque specified in this document.
– Observe a torque of 37 Nm for connections with tin-plated aluminum terminal lugs on copper bar.
– Observe a torque of 60 Nm for connections with tin-plated copper terminal lugs on copper bar.
• When working on the device, use suitable tools only.
• Avoid repeated tightening of live bolted connections as this may result in unacceptably high torques.

11.2 Connecting AC Cables

11.2.1 Cable and Terminal Lug Requirements

Cables:
☐ Use copper or aluminum cables only.
☐ Maximum cable cross-section: 300 mm
☐ AC cables must be designed for maximum voltages of 1,600 V to ground, with a root-mean-square value of 800 V.
☐ All cables of the line conductors must be of the same length.
50 SCCPXT-IA-D7-en-42
2
SMA Solar Technology AG
Installation Manual