FLASH CARD MATERIAL

• Area of circle is 3.14 3 radius

• Area of cylinder is depth 3 3.14 3 radius• Length 3 width 3 height = volume
• 2.54 cm/inch
• 3.28 feet per meter

• Wind category B is urban/suburban or wooded with close obstructions (typical)

• Wind category C is scattered obstructions

• Wind category D is no obstructions and wide open
• Wind category A is no longer in use
• Roof zone 3 = corners

• Roof zone 2 = edges

• Roof zone 1 = middle (best for solar)
• PV source circuit is between PV and combiner
• PV output circuit is after parallel connections in combiner
• PV maximum current definition = Isc 3 1.25Memorize and familiarize
• PV continuous current = Isc 3 1.56
• Continuous current for other than PV source and output circuits is 125%
• 156% ampacity correction only used for PV source and output circuits
• 156% not used with conditions of use; use 125% and compare
• OCPD = overcurrent protection device = fuse or circuit breaker
• OCPD size is maximum current × 1.25 and round up
• If disconnects are in different locations, then directory or plaque required at each disconnect• PV wire used for ungrounded arrays in free air
• Round-down string sizing for cold temperature high Voc calculations
• Round-up string sizing for hot temperature low Vmp calculations
• Rapid shutdown of conductors within 10 feet outside and 5 feet inside building• Pilot hole 67–80% of lag bolt size
• 3 ft space at roof ridge for fire department
• For fine-stranded cable use fine-stranded lugs
• No different orientations within source circuits
• Time of use rates are usually more expensive on summer afternoons
• Tiered utility rates are more expensive as you use more
• Sine wave is less harmonic distortion
• Conductors in conduit outside have to be wet-rated.
• Array gets 80% STC irradiance (current) at 800 watts per square meter
• Multimodal inverter, utility shuts down, power critical loads
• A grounded conductor on an insulated lug is good for measuring voltage
• A grounded conductor is always white or gray
• PV connectors are polarized
• Bypass diode failure usually decreases voltage by one-third of a module voltage• 120/240 is called split phase or single phase
• 120V inverter has single pole ac disconnect/breaker
• No multiwire branch circuit sign is required with 120V inverter
• No more than six switches to turn off PV systems on a building in a single enclosure or group of enclosures• No disconnect on grounded conductor with exceptions for GFDI, AFCI and maintenance.• PV source and output circuits must be separated from other circuits
• PV circuits must be polarized, marked, latching and identified• Load break rated manual disconnect within six feet of combiner required
• Shading short edge of module typically kicks in all bypass diodes and bypasses module• Interactive inverters do not need clamped breaker
• Bond rails to each other
• Max dc disconnect height under normal circumstances is 6.5 feet
• For lightning use lightning protection system and surge protection
• Add acid to water so acid doesn’t splash
• No disconnect or fuse on grounded conductor
• Designated safety person cannot have other duties (distractions)
• No dc disconnect in bathroom (wet feet)
• Do not bond neutral in two places (dc disconnect and inverter GFCI)
• Person who puts on the lockout tagout removes it
• Insulation tester is megohmmeter or Megger
• If disconnects not near each other use plaque or directory
• Battery bank sign should indicate grounded conductor and max voltage
• Equalization and cold temperature battery corrections increase max voltage

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