5 System design
Please use the equipment, connectors, wires and rack which match with solar power system.
In a particular system, be sure to apply the same type of modules. Please refer to the short-circuit
current (Isc) and open circuit voltage (Voc) showing on modules’ label as proper value to install
and design when determining settling parameters such as rated voltage, the wire capacity, fuse,
the controller capacity and module output power of relevant parts of PV system.
In normal outdoor conditions, the generated current and voltage maybe different from the
parameters listed in Table. Parameter table is measured under standard test conditions (STC), so
concerning settling parameters of other parts of photovoltaic power generation system, such as
rated voltage, the wire capacity, fuse, the controller capacity and module power output, it shall
refer to the short-circuit current (Isc) and open circuit voltage (Voc) noted on modules’ label, with
the redundancy value of 125% for design and installation.
Make sure the array of modules installed within the Maximum permitted system voltage and
the rating current and voltage of the sub-equipment such as regulators and inverters.
The connection of modules: in accordance with system design, requirements of output
voltage and current, modules can be series or parallel connected by their connecting wires; the
maximum number of modules in series (N) is equal to the maximum system voltage Vmax divided
by the open circuit voltage Voc of one single module; the number of modules in parallel is related
to the selection of electrical equipment (inverters, controllers) under standard test conditions.
Max System voltage≥
N*Voc*[1+TCvoc*Tc(voc)* (Tmin-25)];
N No modules in series;
Voc Open circuit voltage of each module(refer to product label or data sheet);
Tc(voc) Thermal coefficient of open circuit voltage for the module(refer to data sheet);
Tmin The lowest ambient temperature.
5.1 Location Selection
5.1.1 The module should be installed at an ambient temperature of –40 °C to +40 °C. The
module’s limit working ambient temperature range is from –40 °C to +85 °C.
5.1.2 The maximum altitude for HT PV module is 2000m.