SMA Sunny Island 4248U, Инструкция по установке и эксплуатации

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SI4248U Manual Installation Manual
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The Sunny Island 4248U also supports the automatic operation of 2-wire start generators as
a standard feature. The optional GenMan unit enables the inverter to operate multiple-wire-
start generators. The GenMan option is available from your local distributor/dealer. Manual-
start type generators may also be used.
The terminal blocks are grouped according to function. This helps keep the wires for the
different options together and makes for a more organized wiring compartment.
Conductor Types and Sizes
Generator AC Input
The inverter can accept and pass through up to 56 Amps from an external generator. Per the
NEC, a factor of 1.25 must be applied when sizing conductors and overcurrent devices.
Therefor, a value of 70 Amps must be used when sizing conductors and devices. Circuit
conductors from the generator, operating at 56 Amps, should be sized at 6 AWG and the
circuit should be protected with a 70 Amp overcurrent device (circuit breaker or fused
disconnect). The inverter will accept 4 AWG conductors. All wire should be rated at 75° C
minimum. For further information, see NEC Table 310-16.
Typical conductors for this application would be THHN or THWN-2 installed in conduit. Long
distances between the generator and the inverter may require larger conductors to compensate
for excessive voltage drops.
With a 70 Amp overcurrent device in the generator-to-inverter circuit, an 8 AWG equipment
grounding conductor will be needed in this circuit. (See NEC Table 250.122.) The conductor
can be bare or have green insulation or green markings.
If the circuit conductors are oversized to compensate for voltage drop, the equipment-
grounding conductor must also be oversized. (See NEC 250.122(B)).
AC Output Circuit
NOTE: All electrical installation must be done in accordance with the local and
National Electrical Code ANSI/NFPA 70.
The maximum continuous AC current
of the Sunny Island 4248U is 35 A AC.
The rated inverter output is 4200 W at 120 V AC. The continuous AC output current is 35 A.
For sizing conductors, the NEC requires that this current be increased by a factor of 1.25
yielding a current of 43.75 amps. The output conductors should be sized to carry at least 50
amps and protected by a 50 amp overcurrent device. Therefore, the minimum conductor size
required by the NEC is 8 AWG at 70 °C, even if the inverter is not used at full power.
However, if the inverter is going to be connected to a generator capable of delivering 56 A to
the inverter, then the inverter output conductors must be sized at 6 AWG and protected with a
70 A overcurrent device. See above and NEC Table 310.16.
Typical conductors for this application would be THHN or THWN-2 installed in conduit.