Installation Guide
REC Installation Manual - REC Alpha Series - UL 6
Rev A . Ref: NE
ELECTRICAL INSTALLATION
ELECTRICAL REQUIREMENTS
i) System Requirements
REC solar panels are only for use where they meet the specific technical requirements of the complete system. Ensure other components will not cause
mechanical or electrical damage to the panels. Only panels of the same type and power class should be connected.
ii) String configuration
When using string configuration, plan and execute it according to the inverter manufacturer’s instructions. The number of panels connected to an inverter
must be within the inverter voltage limits and operating range. Do not exceed the total system voltage permied by the manufacturer, nor under any
circumstance exceed the maximum system voltage as stated in the technical specifications for the product at the rear of this manual. The maximum system
fuse rating and the maximum reverse current for each panel can be found in the technical specifications for the product at the rear of this manual.
iii) String connection
If panels are connected in series, they must have the same ampere rating. If panels are connected in parallel, they must have the same voltage rating.
The maximum number of panels that can be connected in series or parallel depends upon system design, type of inverter and environmental conditions.
Panel and string configuration must correspond to the specifications of other system components e.g., inverter. Refer to the reverse current rating of
the panel as indicated in the technical characteristics section to the rear of this manual or on the panel datasheet.
iv) Wiring
Wiring installation shall be in accordance with the National Electric Code (NEC) (or CSA C., Safety Standard for Electrical Installations, Canadian
Electrical Code, Part where applicable). To minimize voltage surges (e.g., indirect lightning strikes), cables of the same string must be bundled together
so loops are as small as possible. String configurations must be checked before commissioning. If open circuit voltage (V
oc
) and short circuit current (I
sc
)
deviate from specification, this may indicate a configuration fault. Correct DC polarity must be observed at all times.
v) Electrical Ratings
Electrical ratings are within a specific tolerance of measured values at Standard Test Conditions (STC) as given in the technical characteristics for each
panel at the rear of this manual. Under normal conditions, a photovoltaic panel is likely to experience conditions that produce more current and/or voltage
than reported at STC. The requirements of the NEC in Article must be followed to address these increased outputs. In installations not under the
requirements of the NEC, the values of I
SC
and V
OC
marked on the panels must be multiplied by a factor of . (or according to local regulations) when
determining component voltage ratings, conductor ampacities, overcurrent device ratings and size of controls connected to the PV output.
MECHANICAL INSTALLATION
FIRE GUIDELINES
REC Alpha panels have a Type fire rating according to UL. The fire performance rating of the panels is only valid when mounted in the manner
specified in this installation manual. The complete system fire class rating is to be achieved by the combination of panel fire performance type and
UL certified mounting structure for a non-BIPV panel. Please refer to mounting structure UL listing for System Fire Classification. Any
specific limitations on the inclination or accessories required to maintain a specific System Fire Class Rating must be clearly specified in the mounting
system manufacturer’s installation instructions and UL certification. Utilize the following fire safety guidelines when installing REC panels:
• Check with all relevant local authorities for fire safety requirements for any building or structure on to which the panels will be installed,
• The system design must ensure that it can be easily accessed in the event of a building fire,
• Check with relevant authorities for applicable regulations concerning setbacks or other placement restrictions that may apply for roof-mounted arrays,
• The use of DC ground fault interrupters is recommended. This may also be required by local and national codes,
• All electrical appliances are a fire risk. The panel must be mounted over a fire retardant roof covering rated for the application and a distance of at
least . in ( mm) between the panel and the mounting surface, to allow the free circulation of air beneath the panels at all times.
ORIENTATION
The optimal mounting position of panels results in the sun’s rays falling perpendicular (i.e., at °) to the surface. To maximize system output, panels should
be installed at the optimum orientation and tilt angle. The specifics of this depend on location and can be calculated by a qualified system designer. All
panels in a string should, wherever possible, have the same orientation and tilt to ensure the system does not underperform due to mismatched outputs.
The solar panels must not be exposed to artificially concentrated light.
ENVIRONMENTAL FACTORS
REC solar panels are designed to provide decades of durable and stable output in installations up to ( m) above sea level. Ambient
operating temperatures must be between -° - °F (-° and +°C).
For further information regarding installations on water platforms, e.g., floating pontoons, see Annex 1 at the rear of this manual.
The panels are not suitable for installation in potentially hazardous locations nor should they be installed in the following locations:
• Near sources of flammable gas or vapor e.g., gas stations, gas containers or spray paint facilities,
• Near open flames,
• Under water or in water features,
• Where exposed to sulfur e.g., near sulfur springs or volcanoes,
• Where the panels may be exposed to harmful chemicals.
Ensure panels are not exposed to direct contact with salt water/spray.