Hoymiles MI-500 User manual

Version B1.0 @2019

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MI-500/MI-600/MI-700
About Microinverter
This system is composed of a group of Microinverters that convert direct current (DC) into alternating
current (AC) and feeds it into the public grid. The system is designed for the incorporation of one
Microinverter for two photovoltaic modules. Each Microinverter works independently that guarantees the
maximum power generation of each photovoltaic module. This setup enables user to control the production
of a single photovoltaic module directly, consequently improving the flexibility and reliability of the system.
About the manual
This manual contains important instructions for the MI-500/MI-600/MI-700 Microinverter and must be read
in its entirety before installing or commissioning the equipment. For safety, only qualified technician, who
has received training or has demonstrated skills can install and maintain this Microinverter under the guide
of this document.
Other Information
Product information is subject to change without notice. User manual will be updated frequently, please
refer to Hoymiles official website at www.hoymiles.com for the latest version.

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MI-500/MI-600/MI-700
Contents
1. Important Notes .................................................................................................................................................. 5
1.1 Product Range.............................................................................................................................................. 5
1.2 Target Group................................................................................................................................................. 5
1.3 Symbols Used............................................................................................................................................... 5
2. About Safety........................................................................................................................................................ 6
2.1 Important Safety Instructions...................................................................................................................... 6
2.2 Explanation of Symbols............................................................................................................................... 7
3. About Product ..................................................................................................................................................... 7
3.1 About Single Unit.......................................................................................................................................... 7
3.2 Highlights....................................................................................................................................................... 8
3.3 Terminals Introduction................................................................................................................................. 8
3.4 Dimension...................................................................................................................................................... 9
4. About Function.................................................................................................................................................... 9
4.1 Work Mode.................................................................................................................................................... 9
5. About Installation.............................................................................................................................................. 10
5.1 Accessories................................................................................................................................................. 10
5.2 Installation Precaution............................................................................................................................... 11
5.3 Space Distance Required......................................................................................................................... 11
5.4 Preparation.................................................................................................................................................. 12
5.5 Installation Steps........................................................................................................................................ 13
6. Troubleshooting................................................................................................................................................ 16
6.1 Troubleshooting List .................................................................................................................................. 16
6.2 Status LED Indicator.................................................................................................................................. 17
6.3 On-site Inspection (For qualified installer only) ..................................................................................... 17
6.4 Routine Maintenance................................................................................................................................. 18
7. Sample Wiring Diagram................................................................................................................................... 19
8. Decommissions................................................................................................................................................. 20
8.1 Decommissions.......................................................................................................................................... 20
8.2 Storage and Transportation...................................................................................................................... 20
8.3 Disposal....................................................................................................................................................... 20
9. Technical Data.................................................................................................................................................. 21
9.1 DC Input....................................................................................................................................................... 21

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MI-500/MI-600/MI-700
9.2 AC Output.................................................................................................................................................... 21
9.3 Efficiency, Safety and Protection............................................................................................................. 22
9.4 General Data............................................................................................................................................... 22

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MI-500/MI-600/MI-700
1. Important Notes
1.1Product Range
This manual describes the assembly, installation, commissioning, maintenance and failure search
of the following model of Hoymiles Microinverter:
MI-500
MI-600
MI-700
Note: “500” means 500W, “600” means 600W, “700” means 700W.
1.2Target Group
This manual is only for qualified technician, who has been trained or has demonstrated skills can
install and maintain this Microinverter under the guide of this document for safety purpose.
1.3Symbols Used
The safety symbols in this user manual are show as below.
Symbol
Usage
Indicates a hazardous situation that can result in deadly electric
shock hazards, other serious physical injury, or fire hazards.
Indicates directions which must be fully understood and followed in
entirety in order to avoid potential safety hazards including
equipment damage or personal injury.
Indicates this points out that the described operation must not be
carried out. The reader should stop, use caution and fully
understand the operations explained before proceeding.

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MI-500/MI-600/MI-700
2. About Safety
2.1 Important Safety Instructions
The MI-500/MI-600/MI-700 Microinverter is designed and tested according to international safety
requirements. However, certain safety precautions must be taken when installing and operating
this inverter. The installer must read and follow all instructions, cautions and warnings in this
installation manual.
All operations including transport, installation, start-up and maintenance, must be carried out by
qualified, trained personnel. 
Before installation, check the unit to ensure free of any transport or handling damage, which could
affect insulation integrity or safety clearances. Choose installation location carefully and adhere to
specified cooling requirements. Unauthorized removal of necessary protections, improper use,
incorrect installation and operation may lead to serious safety and shock hazards or equipment
damage.
Before connecting the Microinverter to the power distribution grid, contact the local power
distribution grid company to get appropriate approvals. This connection must be made only by qualified
technical personnel. It is the responsibility of the installer to provide external disconnect switches and
Over current Protection Devices (OCPD).
Only one photo voltaic module can be connected to one input of the inverter. Do not connect
batteries or other sources of power supply. The inverter can be used only if all the technical
characteristics are observed and applied.
Do not install the equipment in adverse environment conditions such as flammable, explosive,
corrosive, extreme high or low temperature, and humid. Do not use the equipment when the safety
devices do not work or disabled.
Use personal protective equipment, including gloves and eye protection during the installation.
Inform the manufacturer about non-standard installation conditions.
Do not use the equipment if any operating anomalies are found. Avoid temporary repairs.
All repairs should be carried out using only qualified spare parts, which must be installed in
accordance with their intended use and by a licensed contractor or authorized Hoymiles service
representative.
Liabilities arising from commercial components are delegated to their respective manufacturers.
Anytime the inverter has been disconnected from the public network, please be extremely caution
as some components can retain charge sufficient to create a shock hazard. Prior to touching any part
of the inverter please ensure surfaces and equipment are under touch safe temperatures and voltage
potentials before proceeding.
Hoymiles accepts No liability for damage from incorrect or improper operation
Electrical Installation & Maintenance shall be conducted by licensed electrician and shall comply
with Local Wiring Rules

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MI-500/MI-600/MI-700
2.2 Explanation of Symbols
Symbol
Usage
Treatment
To comply with European Directive 2002/96/EC on waste Electrical and
Electronic Equipment and its implementation as national law, electrical
equipment that has reached the end of its life must be collected separately
and returned to an approved recycling facility. Any device no longer required
must be returned to an authorized dealer or approved collection and
recycling facility.
Caution
Do not come within 8 inches (20cm) of the microinverter for any length of
time while it is in operation.
Danger of high voltages
Danger to life due to high voltage in the microinverter.
Beware of hot surface
The inverter can become hot during operation. Avoid contact with metal
surfaces during operation.
CE mark
The inverter complies with the requirements of the Low Voltage Directive for
the European Union.
Read manual first
Please read the installation manual first before installation, operation and
maintenance.
3. About Product
3.1 About 2 in 1 Unit
“The world’s First Daisy-Chain 2 in 1 Unit Microinverter” with extremely wide DC input operating
voltage range (16-60V) and low start-up voltage (22V only).
Hoymiles 2 in 1 unit Microinverter MI-500/MI-600/MI-700 is the perfect selection for PV system with
uneven number of panels with world’s NO.1 CEC weighted efficiency – 96.50% (peak efficiency
96.70%) in 2015.

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MI-500/MI-600/MI-700
3.2 Highlights
- Maximum output power up to 500/600/700W; Adapted to 60 & 72 cells PV panels.
- Peak efficiency 96.70%; CEC weighted efficiency 96.50%.
- Static MPPT efficiency 99.80%; Dynamic MPPT efficiency 99.76% in overcast weather.
- High reliability: NEMA6 (IP67) enclosure; 6000V surge protection
3.3 Terminals Introduction
Object
Description
A
AC Connector (male)
B
AC Connector (Female)
C
DC Connectors

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MI-500/MI-600/MI-700
3.4 Dimension
4. About Function
4.1 Work Mode
Normal: Under this mode, Microinverter is operating normally and convert DC power into AC power to
support the house loads and feed in to Public Grid.
Zero Export Control: Under this mode Microinverter’s generation is limit base on the current house
loads, there will be no extra power feed in to the Public Grid.
Stand by: There are several circumstance that Microinverter will stay in Standby mode:
- The current condition is contradicted with Microinverter operating requirement.
- No house loads or the Export control value has been set as “0” on the DTU under the Zero Export
Control mode.

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MI-500/MI-600/MI-700
5. About Installation
5.1 Accessories
Note: all accessories above are optional, please contact our sales to purchase base on the quantity
required on actual installation.
Object
Description
A
AC Extension Cable
B
AC End Cable (Female) , 2m 12 AWG cable.
C
AC Female Connector
D
AC Male Connector
E
AC Male End Cap, IP67.
F
AC Female End Cap, IP67.
G
Screw, 2 pcs of M8*25 screws to tighten microinverter on the frame.
H
AC/DC Connector Unlock Tool.

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MI-500/MI-600/MI-700
5.2 Installation Precaution
Please install the Microinverter and all DC connections under the PV module to avoiding direct sunlight,
rain exposure, snow layup, UV etc.
Note: For some countries the DTU will be required to meet the local grid regulation (e.g. G98/99 for
UK).
5.3 Space Distance Required
Please install the Microinverter at least 500mm above the ground/roof. Please contact with Hoymiles
technical engineer if there is any special circumstance.

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MI-500/MI-600/MI-700
5.4 Preparation
Installation of the equipment is carried out based on the system design and the place in which the
equipment is installed.
The installation must be carried out with the equipment disconnected from the grid (power
disconnect switch open) and with the photovoltaic modules shaded or isolated.
Referring to the Technical Data to make sure the environmental conditions fit the
microinverter’s requirement (degree of protection, temperature, humidity, altitude, etc.)
To avoid power de-rating due to an increase in the microinverter internal temperature, do not
expose it to direct sunlight.
To avoid overheating, always make sure the air flow around the inverter is not blocked.
Do not install in places where gasses or flammable substances may be present.
Avoid electromagnetic interference that can compromise the correct operation of electronic
equipment.
When choosing the position of installation, comply with the following conditions:
Install only on structures specifically conceived for photovoltaic modules (supplied by
installation technicians).
Install Microinverter underneath of the photovoltaic modules to make sure it works in the
shadow. If this condition cannot be met, might trigger the inverter production de-rating.
Fig.1 Installation position of microinverter

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MI-500/MI-600/MI-700
5.5 Installation Steps
Step 1. Install Microinverter
A. Mark the approximate center of each panel on the frame.
B. Install the Microinverter shown as below. The silver cover side should be up.
C. Tighten the screw and fix the inverter on the frame.
Observe the certification documents concerning the maximum number of Micro-inverters
permitted for installation at each cable section!
The Microinverter must be under the module, out of long-term exposure to direct sunlight or
rain.
Step 2. Connect AC Cables of Microinverter
A. Plug the AC connector of the first microinverter into the connector of the second microinverter,
and so for the rest, to form a continuous AC branch circuit
B.Install the AC EndCapontheopen ACconnectorof thelastmicroinverterin theAC branch circuit.

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MI-500/MI-600/MI-700
Step 3. Connect AC End Cable
A. Connect the AC Female connector on the side of AC End cable to the adjacent Microinverter’s
AC Male connector.
B. Connect the other side of the AC End Cable to the distribution box, and wire it to the local grid
network. Close the distribution box after the wiring is completed.
Note: Brown Wire: L Blue Wire: N Yellow/Green Wire: Ground
Step 4. Create an Installation Map
A. Peel the removable serial number label from each microinverter (The position of the label is
shown as below).

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MI-500/MI-600/MI-700
B. Affix the serial number label to the respective location on the installation map (Please refer to
the appendix for the installation map).
Step 5. Connect PV Modules
A. Mount the PV modules above the microinverters.
B. Connect the PV modules’ DC cables to the DC input side of the microinverter.
The recommended installation need to keep the Microinverter underneath the photovoltaic
modules, so that the Microinverters can operate in the shadow. Direct sunlight exposure may
effect on the performance as well as the lifetime to the Microinverter.
The length of the DC cable that connecting the Microinverter and module need to be less than
3m.

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MI-500/MI-600/MI-700
Step 6. Energize the System
A. Turn on the AC breaker for the branch circuit.
B. Turn on the main AC breaker for the house. Your system will start to generate power about
two-minute waiting time.
Step 7. Monitoring System Set Up
Refer to the DTU User Manual or the DTU Quick Install Guide to Install the DTU and Set up
Monitoring System.
6. Troubleshooting
6.1 Troubleshooting List
Status
Code
Solution
01
Please contact your installer.
02
Please contact your installer.
03
Waiting for AC voltage recover, if the code appears frequently please contact
your installer to check the AC wiring.
04
Please Contact your installer, and provide Panel specs.
05
Please contact your installer to check the DC side installation and PV
configuration.
06
Please contact your installer.
07
Please check the am temperature and installation environment.
08
Waiting for AC voltage recover, if the code appears frequently please contact
your installer to check the AC wiring.
09
Waiting for AC frequency recover, if the code appears frequently please contact
your installer.
10
Please try firmware upgrade.
12
Please try reboot or firmware upgrade.
13
Please try reboot or firmware upgrade.
14
Please contact your installer.
15
Waiting for AC voltage recover, if the code appears frequently please contact
your installer.
16
Please contact your installer.
20
Please try firmware upgrade.

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MI-500/MI-600/MI-700
6.2 Status LED Indicator
The LED flashes six times at start up. All green flashes indicate normal start up.
Flashing Slow Green (2s gap): Producing power and communicating with DTU.
Flashing Fast Green (4s gap): Producing power and not communicating with DTU.
Flashing Red (1s gap): Not producing power AC grid invalid (Voltage or frequency out of range).
Flashing Red (always): GFDI Fault. The LED will remain red and the fault will continue to be reported
by the DTU.
6.3 On-site Inspection (For qualified installer only)
To troubleshoot an inoperable microinverter, follow the steps in the order shown.
1. Verify the utility voltage and frequency are within ranges shown in the in appendix Technical Data of
this microinverter.
2. Check the connection to the utility grid. Verify utility power is present at the inverter in question by
removing AC, then DC power. Never disconnect the DC wires while the microinverter is producing
power. Re-connect the DC module connectors and watch for five short LED flashes.
3. Check the AC branch circuit interconnection between all the microinverters. Verify each inverter is
energized by the utility grid as described in the previous step.
4. Make sure that any AC breaker are functioning properly and are closed.
5. Check the DC connections between the microinverter and the PV module.
6. Verify the PV module DC voltage is within the allowable range shown in appendix Technical Data of
this manual.
7. If the problem persists, please call Hoymiles customer support.
Warning
Do not try to repair the microinverter. If the troubleshooting fails, please return it to the factory for
replacement.

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MI-500/MI-600/MI-700
6.4 Routine Maintenance
Only authorized personnel are allowed to carry out the maintenance operations and are responsible
to report any anomalies.
Always use the personal protective equipment provided by the employer when carry out the
maintenance operation.
During normal operation, check that the environmental and logistic conditions are correct. Make sure
that the conditions have not changed over time and that the equipment is not exposed to adverse
weather conditions and has not been covered with foreign bodies.
DO NOT use the equipment if any problems are found, and restore the normal conditions after the
fault removed.
Conduct an annual inspection on various components, and clean the equipment with a vacuum
cleaner or special brushes.
Do not attempt to dismantle the Microinverter or make any internal repairs! In order to preserving
the integrity of safety and insulation, the Microinverters are not designed to allow internal repairs!
The AC output wiring harness (AC drop cable on the Microinverter) cannot be replaced. If the cord is
damaged the equipment should be scrapped.
Maintenance operations must be carried out with the equipment disconnected from the grid (power
switch open) and the photovoltaic modules obscured or isolated, unless otherwise indicated.
For cleaning, do not use rags made of filamentary material or corrosive products that may corrode
parts of the equipment or generate electrostatic charges.
Avoid temporary repairs. All repairs should be carried out using only genuine spare parts.

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MI-500/MI-600/MI-700
7. Sample Wiring Diagram
Fig.2 Single Phase Wiring Diagram
Fig.3 Three phase wiring diagram

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MI-500/MI-600/MI-700
DTU connects the power production of each microinverter. If the asymmetry current is going to
exceed 16 A, DTU will send stop signal to one or more microinverters to let the asymmetry current
lower than 16A.
Each branch should provide a 20A circuit breaker, but no need for central protection unit.
8. Decommissions
8.1 Decommissions
Disconnect the inverter from DC input and AC output; remove all connection cable from the
Microinverter; remove the Microinverter from the frame.
Please pack the Microinverter with the original packaging, or use the carton box that can afford 5kg
weight and can be fully closed if the original packaging is no longer available.
8.2 Storage and Transportation
Hoymiles packages and protects individual components using suitable means to make the transport
and subsequent handling easier. Transportation of the equipment, especially by road, must be carried
out by suitable ways for protecting the components (in particular, the electronic components) from
violent, shocks, humidity, vibration, etc. Please dispose the packaging elements in appropriate ways
to avoid unforeseen injury.
It is the customer’s responsibility to examine the condition of the components transported. Once
receiving the Microinverter, it is necessary to check the container for any external damage and verify
receipt of all items. Call the delivering carrier immediately if damage or shortage is detected. If
inspection reveals damage to the inverter, contact the supplier, or authorized distributor for a
repair/return determination and instructions regarding the process.
The microinverter storage temperature is -40-85℃.
8.3 Disposal
- If the equipment is not used immediately or is stored for long periods, check that it is correctly
packed. The equipment must be stored in well-ventilated indoor areas that do not have
characteristics that might damage the components of the equipment.