codes Flashcards
UL 1741
product safety requirements for inverters and other equipment used in both interconnected and stand alone systems
table 310
open air/race way, conduit codes
706.21(E)
a disconnect means is required to isolate the fuse from all sources for servicing
table 690.7
determining the max number of modules depending on max source Voltage
706
energy storage systems
NEC 250.52(A)(3)(1)
dealing with rebar and concrete encasements ?
90.4
The AHJ has
the responsibility for making interpretations of the rules, for deciding on the approval of
equipment and materials, and for granting the special permissions covered by the NEC
705.12 (B)
load side connections must comply with the following six requirements
706.30 (A)
Concealed lithium-ion battery compartments that do not require maintenance can operate at voltages
above 100V in dwellings
Article 300
Wiring Methods
250.97
For circuits over 250 volts where oversized concentric or eccentric knockouts are encounter the raceway needs to be bonded by one of the means listed in 250.92(B) except for (B)(1)
706
energy storage systems (ESS), listed to UL 9540 is NOT subject to field inspection except for field termination
706.23 (B)
Interactive systems must also have a second
independent charge controller to prevent battery overcharge when the grid or loads are not
available to divert excess power
NEC 334.30
USE-2 wire be secured 12” from the junction box
Article 230
services
110.27
all live parts shall be guarded
Article 240
overcurrent devices
710
stand-alone systems
NEC 310.15(B)(16)
At 75⁰C THW, XHHW, THWN should be used
NEC 338.10(B)(4). Article 334.30
Installation methods for exterior USE-2 conductors; USE-2 wire must be strapped and secured between modules at
intervals no more than 4.5”
110.26
Working spaces must be allowed for installers and maintenance personnel to safely work on electrical equipment
Article 691
Large-Scale PV Power
Production Facility
90.1 (purpose)
“is the practical safeguarding of persons and property from hazards
arising from the use of electricity and is not intended as a design specification
or an instruction manual for untrained persons”
250.110
Any conductive battery racks, cases or trays must also have proper equipment grounding
Article 712
DC Microgrids
110.3 (B)
A key element of a safe and code-compliant electrical installation is adherence to product
installation and use instructions included with listed and labeled products
NEC Table 310.15(B)(16)
75 or 90 degree column is good for #8 wire good for 50 Amp breaker
690.41 (B)
most PV systems, residential, and commercial must have ground fault
[NEC 706.23(B)]
Whenever a diversionary charge controller is used, a second independent charge controller is
required to prevent battery overcharge in the event the diversion loads are unavailable or the
diversion charge controller fails
250.12
aluminum either has an anodized coating to reduce corrosion or a thick layer of oxidation as in the case of non-anodized aluminum. In either case, simple bolting of modules to structures, or lugs to modules or structures, will not necessarily provide the necessary bonding and grounding. The NEC generally requires that the installer remove non-conductive coatings prior to making electrical connections
706.23
A charge controller is required in most
PV systems that use battery storage, to prevent damage to the batteries or hazardous conditions
resulting from overcharging
IEEE 1547
establishes the technical requirements for interconnecting all types of distributed generation
equipment, including PV, fuel cells, wind generators, reciprocating engines, microturbines, and
larger combustion turbines with the electrical power system. It also establishes requirements
for testing, performance, maintenance and safety of the interconnection, as well as response to
abnormal events, anti-islanding protection and power quality
690.34
Junction boxes do not have to be readily accessible, but must
permit ready access by temporarily removing modules connected by flexible wiring methods
Article 690.45(A) refers to Table 250.122
Where no overcurrent protection is provided for the PV dc circuit,
an assumed overcurrent device rated at the PV circuit Isc is used to size
the equipment grounding conductor
Article 705
Interconnected Electric
Power Production Sources
IEEE 1547
testing procedures required to ensure that grid-direct inverters conform with safety requirements related to voltage, frequency, synchronization, disturbances, faults, and reconnect time. “islanding”
690.8 (A) (3)
conductor should be sized according to the max continuous current output of the inverter
Article 250.52 (A) (4)
1/0 ground wire = ground ring
Article 690.14 (C)(1)
Requirements and location for Disconnecting Means
90.7, 110.3
Equipment is generally
approved when it is listed, labeled, or evaluated for safety by an approved testing laboratory
[NEC 690.4(B), 705.6].
Certain PV
products are also identified for specific applications and conditions of use, such as inverters
intended for utility interconnection
710.15 (C)
special warning sign is required on
the panel to prohibit the connection of multiwire branch circuits
690.72
self regulating PV charge controller
480.10(C), 110.26
Sufficient working spaces and clearances must be
provided for any battery installations
690.2
installer should be able to clearly identify the different circuits ( DC or AC )
UL 2579
fuses for photovoltaic systems
690.42
The dc system grounding connection must be made at a single point on the PV output circuit
690.72
Active means of charge control is required by the NEC
unless the maximum array charge current for 1 hour is less than
3% of the rated battery capacity measured in amp/hours.
Article 706
Energy Storage Systems
NEC 240.4(D) (7)
copper #10 wire limited to 30 Amp overcurrent device
480.9, 480.10
To prevent battery installations from being classified as hazardous locations, ventilation of explosive
battery gasses is required. However, the NEC does not provide specific ventilation requirements.
Vented battery cells must incorporate a flame arrestor to help prevent cell explosions from external
ignition sources, and cells for sealed batteries must have pressure relief vents
690.49
Where the removal of the utility-interactive inverter or other
equipment disconnects the bonding connection between the
grounding electrode conductor and the photovoltaic source and/or
the photovoltaic output circuit grounded conductor, a BONDING JUMPER shall be
installed to maintain the system grounding while the inverter or
other equipment is removed.
710.15 (A)
the inverter should be large enough to power the total connected load, but is only
required to be as large as the single largest load
110.26
requirements for working spaces
around live electrical equipment
Article 710
Stand-Alone Systems
Article 480
Storage Batteries
Article 250.53 (F)
30” of burial depth for ground ring
UL 1741
standard for inverters, converters, charge controllers and combiner
boxes
PV racking systems are UL standard 2703, meaning?
module clamps, when mechanically attached, have a means to bond the frames of the mods to the rails for equipment grounding purpose
Article 690.14 (D) (1-4)
) Utility-interactive inverters mounted in not-readily –
accessible-locations.
705
AC microgrids
NEC 690.17
The DC and AC disconnects should be on either side of the inverter AKA ‘readily accessible requirement’
Article 310
Conductors for
General Wiring
250, 690.43
The installation of an equipment grounding conductor (EGC) is required for all metal framed PV module systems and any PV array that has exposed conductors in contact with metal support structures, regardless of system voltage ; The EGC can be a conductor, busbar, metallic raceway, or structural component.
UL 2703
standard for racking systems
Article 250
Grounding and Bonding
300.9
conductors in conduit installed outdoors/ rooftops must be water tight; labeled W
Article 240
Overcurrent Protection
UL 4703
standard for PV wire
690.4 (C), 705.6
any PV system equipment, including any electrical power production
sources operating in parallel with a primary source of electricity be installed only by qualified
persons
690.53
The maximum rated output current of the charge controller must be posted on a
sign at the dc disconnect
690.72
max charge rates from PV array multiplied by 1 hour = 3% of battery nominal Ah capacity or greater a charge controller is required
712
DC microgrids
300.5
conductors in conduit installed underground must be water tight; labeled W
NEC 338.10(B) (4).
USE-2 wires should be lifted off of roof ad strapped at 3’ (wire management)
OSHA requirements for battery installations
-Unsealed batteries must be installed in ventilated enclosures to prevent fumes, gases, or
electrolyte spray entering other areas, and to prevent the accumulation of an explosive mixture.
• Battery racks, trays and floors must be of sufficient strength and resistant to electrolyte.
• Face shields, aprons, and rubber gloves must be provided for workers handling acids or
batteries, and facilities for quick drenching of the eyes and body must be provided within
25 feet of battery handling areas.
• Facilities must be provided for flushing and neutralizing spilled electrolyte and for fire
protection.
• Battery charging installations are to be located in designated areas and protected from
damage by trucks.
• Vent caps must be in place during battery charging and maintained in a functioning condition.
480.8
Metal racks must be painted or otherwise treated to resist degradation from electrolyte and
provide insulation between conducting members and the battery cells
690.45
EGC (equip. grounding conductor) size for DC side
706.30 (B)
If batteries are connected in series to produce more than 240 V (nominal), then the batteries
must be connected in a manner that allows the series strings of batteries to be separated into
strings of 240 V or less for maintenance by qualified persons
690.8
code-approved method to determine conductor/wiring
480.10
proper ventilation for vented and sealed battery systems
690.7
The charge controller rated continuous current (sometimes specified as input current, sometimes as output current) must be at least 125% of the PV array short-circuit output current, and the charge controller maximum input voltage must be higher than the maximum system voltage
Article 110
Requirements for
Electrical Installations
UL 1703
standard for PV mods
Article 705.10
Permanent plaque or directory
706.30 (A) exception
First, if routine maintenance is required, which would not be the case for lithium-ion or valve-regulated lead-acid (VRLA) batteries, then the terminals must be guarded to prevent contact during that maintenance. Second, a ground-fault detector-indicator is also required for any ESS operating over 100 volts.
690.31
Spacing between cable management devices for PV wire
Commissioning protocol standards
NFPA 70 (National Fire Protection Association) National Electrical Code and in
particular those Articles relevant to the solar industry: 690, 691, 705, 706, 710, and, in
some projects, 712.
• NFPA 70E Standard for Electrical Safety in the Workplace.
• IEC 62446-1 Grid connected photovoltaic systems – Minimum requirements for system
documentation, commissioning tests and inspection. This standard provides a framework for
system commissioning that is widely accepted in the solar industry.
IEC 62446-1
Grid connected photovoltaic systems – Minimum requirements for system documentation, commissioning tests and inspection
ANSI/ NETA ATS 2017
Standard for Acceptance Testing Specifications for Electrical Power Equipment and Systems
110.26
requirements for working spaces around live electrical equipment
Table 250.122
Where no overcurrent protection is provided for the PV dc circuit, an assumed overcurrent device rated at the PV circuit Isc is used to size the equipment grounding conductor
690.31 (G)
metallic conduit, raceways, and enclosures for PV source and output circuits (DC) that run inside a building/structure
ANSI Z87.1
standard for safety glasses
250.119 and 200.6 (A)
color coding requirements
