User Manual
34
The line-to-line voltage on the HV side of transformer should comply with
local power grid voltage.
A transformer with a tap changer on the HV side is recommended in order to
keep consistent with the grid voltage.
At an ambient temperature of 45
℃
, the transformer can run in 1.1 times of
load for long time.
Transformer with a short-circuit impedance 6% (permissible tolerance:
±
10%) is recommended.
The voltage drop of system cable is no more than 3%.
The DC component that the transformer can withstand is 1% of the
fundamental current at rated power.
For thermal rating, the load curve of the transformer and environment
conditions should be taken into account.
The apparent power of the inverter should never exceed the power of the
transformer. The maximum AC current of all inverters connected in parallel
must be taken into account. If more than 30 inverters are connected to the
grid, contact SUNGROW.
The transformer must be protected against overloading and short circuit.
The transformer is an important part of grid-connected PV generation system.
The fault tolerance capacity of the transformer should be taken into account
at all times. The fault include: system short circuit, grounding fault, voltage
drop, etc.
Take ambient temperature, relative humidity, altitude, air quality, and other
environmental conditions into account when selecting and installing the
transformer.
5.5.2 Requirements for OT/DT Terminal
OT/DT terminals (not included in the delivery scope) are required for fixing AC
cables to the terminal block. Purchase the OT/DT terminals according to the
following requirements.
Specification: M8;
Dimensions: a
≤
30mm / 8.4mm
≤
b
≤
10.5mm / c
≤
16mm