Title: Enphase Micro-Inverter System Installation Recommendations
1Enphase Micro-Inverter SystemInstallation
Recommendations
- Jeff Laughy
- Applications Engineer
2Photovoltaic Cell
Building Block of PV Modules Each cell produces
.5 Vdc Monocrystalline cell - a thin slice cut
from a single crystal of silicon, highest
efficiency 17 Polycrystalline cell liquid
silicon is poured into blocks, then sliced, more
cost efficient, efficiency lower, 15
Monocrystalline Cell
Polycrystalline Cell
3Typical Configurations
54 cells in series 60 cells in series 72 cells
in series produce enough voltage to charge 24V
batteries (24 volt nominal) 84 cells in
series 96 cells in series (32 volt nominal)
4Maximum Power Point
Short Circuit Current Isc 5.75 A Open
Circuit Voltage Voc 47.7 V Max Power Current
Imp 5.25 A Max Power Voltage Vmp 40.0
V
Voltage varies with Temperature Current varies
with Irradiance Power equals Voltage x
Current 5.25 A x 40.0 V 210 Watts
5Series String
Current is equal in a series circuit Lowest
performing module determines the current for the
string
6Micro-inverter Technical Data60 and 72 Cell
Modules, 240 Vac
- Input Data (DC)
- Recommended Input Power (STC) 230 Watts
- Peak Power Tracking Voltage 22V
40V - Maximum DC Voltage
54V - Positive Ground
- Output Data (AC)
- Maximum Output Power 190
Watts - Nominal Output Current .80
Amps - Maximum number of inverters
- per 15 amp branch circuit
15
7Micro-inverter Technical Data,96 Cell Modules,
240 Vac
- Input Data (DC)
- Recommended Input Power (STC) 240 Watts
- Peak Power Tracking Voltage 44V
65V - Maximum DC Voltage
80V - Positive Ground
- Output Data (AC)
- Maximum Output Power 200
Watts - Nominal Output Current .83
Amps - Maximum number of inverters
- per 15 amp branch circuit
14
8Distribution Panel Connections240 Vac Single
Phase
9Voltage Drop Considerations, 240 Vac
The table below provides recommendations for wire
size from the junction box at the beginning of
the Micro-inverter branch to the main load center
based on distance.
10Micro-inverter Technical Data,60 and 72 Cell
Modules, 208 Vac
- Input Data (DC)
- Recommended Input Power (STC) 230 Watts
- Peak Power Tracking Voltage 22V
40V - Maximum Input Voltage
54V - Positive Ground
- Output Data (AC)
- Maximum Output Power 190
Watts - Nominal Output Current .92
Amps - Maximum number of inverters
- per 15 amp branch circuit
21
11Micro-inverter Technical Data,96 Cell Modules,
208 Vac
- Input Data (DC)
- Recommended Input Power (STC) 240 Watts
- Peak Power Tracking Voltage 44V
65V - Maximum Input Voltage
80V - Positive Ground
- Output Data (AC)
- Maximum Output Power 200
Watts - Nominal Output Current .96
Amps - Maximum number of inverters
- per 15 amp branch circuit
21
12Distribution Panel Connections208 Vac Three Phase
13Voltage Drop Considerations, 208 Vac
The table below provides recommendations for wire
size from the junction box at the beginning of
the Micro-inverter branch to the main load center
based on distance. The table is in increments of
3 inverters, always round up to the next
increment.
14Distribution Panel Connections208 Vac Three
Phase with LCF
15The Enphase Micro-Inverter SystemSite Installed
Components
Micro-Inverters One inverter
per-module
Communication Gateway Each gateway
supports 180 inverters
AC Interconnect Cable, End Cap One per
15 amp branch circuit
Junction Box Adapter Plate One per 15
amp branch circuit
16Micro-Inverter System
17Micro-Inverter System
18Branch Circuit Cable Layout
- Inverter branches can be routed horizontally,
- vertically, or a combination of both directions.
- Standard Inverter cable lengths are 3 ft,
extension cables are available in 6 ft, 12 ft and
20 ft lengths.
19Micro-Inverter System
20Micro-Inverter Installation
- Step 1 - Junction Box Adapter Plate
- Step 2 - Attaching the Micro-Inverter
- Step 3 - Connecting the Circuit Cables
- Step 4 - Grounding Conductor Connection
- Step 5 - Installation Map
- Step 6 - Module Connection
Indicates a fact or feature very important for
the safety of the user.
Indicates an Enphase recommendation or best
practice.
21Junction Box Adapter Plate
- Mount an outdoor rated
- junction box to the adapter
- plate.
- This junction box is used to
- connect the inverter pigtail
- to the cable or conduit that
- has been run to the main
- load center.
22Junction Box Adapter Plate
- Install the Enphase
- adapter plate and
- junction box assembly
- to the module racking.
23Junction Box Adapter Plate
- Connect the Enphase
- AC interconnect
- cable to the junction
- box.
- Standard Inverter
- pigtail length is 6 ft,
- longer pigtails are
- available in 12 ft
- and 20 ft lengths.
24Attaching the Micro-inverter
- Mark the approximate
- centers of each PV
- module on the racking
- system. (module width
- plus 1 for clips)
- Avoid aligning
- the Inverter with the
- Module junction box.
25Attaching the Micro-inverter
- Attach the Enphase
- Micro-inverters at
- the module centers
- using the racking
- manufacturers
- hardware.
- Orient the inverter so
- that the inverter
- connector with male pins
- is toward the load center.
26Connecting the Circuit Cables
- Connect the first
- Enphase Micro-inverter
- to the Enphase AC
- interconnect cable.
- Orient the inverter
- so the male connector
- is toward the junction
- box.
27Connecting the Circuit Cables
- Connect the
- remaining Enphase
- Micro- Inverters.
- Ensure that the
- connectors are
- securely locked.
- Use cable ties to secure
- the AC cables to the
- racking.
28Connecting the Circuit Cables
- Do not exceed the
- maximum number of
- Enphase Micro-inverters
- per branch circuit listed
- on the product label.
29Connecting the Circuit Cables
- Attach the included
- protective end cap
- onto the unused
- connector of the
- last Enphase Micro-
- inverter.
30Grounding the Conductor Connection
- Connect the grounding
- conductor to each
- Enphase Micro-inverter
- in the location marked
- Grounding Electrode
- Terminal.
31Grounding Conductor Connection
- Route a single grounding
- conductor through all the
- inverters.
- Connect a short length of
- Ground wire to each module
- Separate conductors
- for the modules and
- inverters may be installed.
32Installation Map
- Peel one of the two
- labels from each
- Enphase Micro-
- inverters and place
- the label on the
- Enphase installation
- map to show the
- relative physical
- location of the
- modules.
33Module Connections
- Connect the PV
- modules to the
- Enphase Micro-
- inverters.
34DC Disconnection Procedure
- Do not disconnect module connectors under
load. - Disconnecting AC first will eliminate the
DC - current prior to disconnecting the module.
- Individual modules could also be covered
- prior to disconnecting cables during daylight
hours -
35Micro-Inverter System
36Energy Management Unit Installation
- Step 1 - Power Connection
- Step 2 - Network Connection
- Step 3 - EMU Startup
- Step 4 - Enlighten Registration
- Step 5 - Fax the Inverter info
- Step 6 The Enlighten web site
Indicates a fact or feature very important for
the safety of the user.
Indicates an Enphase recommendation or best
practice.
37Power Connection
- Connect the power cord
- to the EMU power inlet,
- then plug the power
- cable into a power outlet
- somewhere near your
- internet router.
38Power Connection
- Do not plug the EMU
- into a power strip or
- Uninterruptable Power
- Supply (UPS), the surge
- suppression or filtering
- components of the power
- strip could disrupt the EMU
- power line communications.
39Network Connection
- Plug the provided CAT5/6
- twisted pair Ethernet
- patch cable into the RJ45
- on the EMU.
- Plug the other end
- of the Ethernet
- patch cable into the
- broadband router.
40EMU Startup
- It takes less than 5 minutes
- for the EMU to boot.
- You know that it has
- booted when it displays
- An IP address, and
- shows WEB both in the
- onboard LCD window.
41EMU Startup
- A newly installed EMU will
- scan for 1 week.
- To restart a scan or perform
- a communication check once
- the EMU has booted, press
- and hold the button labeled
- SCAN on the front for 2
- seconds. This will enable
- The LCD panel menu.
42EMU LCD Panel Menu
- Continue holding the SCAN
- button until the desired menu
- option appears.
- Release the SCAN button to
- select a menu option.
43EMU Startup
- Device Scan
- During a device scan the display shows the
following - Communication Check
- After a communication Check the display shows
the following
44EMU Startup
- 192.168.2.140
- (or whatever the local IP address is)
- WEB
- (indicating that it made a connection to the
internet) - (n)W
- (indicating the present power production in
watts) - (n)kWh
- (indicating the lifetime watt hours reported to
this EMU) - (n)
- (indicating the number of Micro-Inverters
reporting to the EMU)
45Enlighten Registration
- Register the EMU with the Enlighten web site by
- entering the EMU serial number and the site
- information.
46Fax the Micro-inverter Information
- Fax the completed
- installation map from
- the Micro-inverter
- installation to Enphase at
- 707-763-0784.
47The EnlightenTM Website
- Once the website is
- configured, energy data
- will be displayed on the
- Enphase Enlighten
- website on a per PCU,
- per module basis.
48Branch Circuit Calculations, 240 Vac
- Circuit Current Calculation
- Maximum Output Power 175 Watts AC
- 175 W 240 V .73 Amps
- .73 x 16 inverters 11.68 amps / branch
- Overcurrent Protection Calculation
- 11.68 x 1.25 14.6 Amps
- Conclusions
- Install 1 to 16 Inverters per branch, up to 2800
Watts - Minimum 2 Pole 15 Amp circuit breaker, 14 AWG
wire size.
49Branch Circuit Calculations, 208 Vac
- Circuit Current Calculation
- Maximum Output Power 175 Watts AC
- 175 W 208 V .84 Amps
- .84 x 8 inverters per phase 6.73 amps per phase
- 6.73 x 1.73 11.64 amps per leg
- Overcurrent Protection Calculation
- 11.65 x 1.25 14.55 Amps
- Conclusions
- Install 1 to 24 inverters per branch, up to 4200
Watts - Minimum 3 Pole 15 Amp circuit breaker, 14 AWG
wire size.
50Performance Monitoring Reporting Service
Enphase Energy is an approved PMRS provider, the
Energy Tracking LLC, Web Enabled Meter
communicates directly with the Enphase EMU. The
metered data is then forwarded to the
participating utility.