Huawei MERC Series User manual

MERC Smart PV Optimizer
User Manual
Issue 03
Date 2022-11-30
HUAWEI DIGITAL POWER TECHNOLOGIES CO., LTD.

Copyright © Huawei Digital Power Technologies Co., Ltd. 2022. All rights reserved.
No part of this document may be reproduced or transmitted in any form or by any means without prior
written consent of Huawei Digital Power Technologies Co., Ltd.
Trademarks and Permissions
and other Huawei trademarks are the property of Huawei Technologies Co., Ltd.
All other trademarks and trade names mentioned in this document are the property of their respective
holders.
Notice
The purchased products, services and features are stipulated by the contract made between Huawei
Digital Power Technologies Co., Ltd. and the customer. All or part of the products, services and features
described in this document may not be within the purchase scope or the usage scope. Unless otherwise
specied in the contract, all statements, information, and recommendations in this document are
provided "AS IS" without warranties, guarantees or representations of any kind, either express or implied.
The information in this document is subject to change without notice. Every eort has been made in the
preparation of this document to ensure accuracy of the contents, but all statements, information, and
recommendations in this document do not constitute a warranty of any kind, express or implied.
Huawei Digital Power Technologies Co., Ltd.
Address: Huawei Digital Power Antuoshan Headquarters
Futian,Shenzhen 518043
People's Republic of China
Website: https://e.huawei.com
Issue 03 (2022-11-30) Copyright © Huawei Digital Power Technologies Co., Ltd. i

About This Document
Purpose
This document describes the functions, electrical specications, and structure of
the smart photovoltaic (PV) optimizer.
Figures provided in this document are for reference only.
Intended Audience
This document is intended for:
● Sales engineers
● Technical support engineers
● Maintenance engineers
Symbol Conventions
The symbols that may be found in this guide are dened as follows.
Symbol Description
Indicates a hazard with a high level of risk which, if
not avoided, will result in death or serious injury.
Indicates a hazard with a medium level of risk which,
if not avoided, could result in death or serious injury.
Indicates a hazard with a low level of risk which, if
not avoided, could result in minor or moderate
injury.
Indicates a potential hazard which, if not avoided,
could result in equipment damage, data loss,
performance deterioration, or unanticipated results.
NOTICE is used to address practices not related to
personal injury.
MERC Smart PV Optimizer
User Manual About This Document
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Symbol Description
Supplements the important information in the main
text.
NOTE is used to address information not related to
personal injury, equipment damage, and
environment deterioration.
Change History
Changes between document issues are cumulative. The latest document issue
contains all updates made in previous issues.
Issue 03 (2022-11-30)
● Updated 2.2 Structure.
● Updated 2.3 Conguration Principles.
● Updated 2.4 Application Scenarios.
● Updated 3.1 Setting the Physical Layout of the Smart PV Optimizers.
● Updated 3.2 Detecting Optimizer Disconnection.
● Updated 3.5 Replacing an Optimizer.
Issue 02 (2022-09-20)
● Updated 2.3 Conguration Principles.
● Updated 3.4 Troubleshooting.
● Updated 4 Technical Specications.
Issue 01 (2022-08-30)
This issue is the rst ocial release.
MERC Smart PV Optimizer
User Manual About This Document
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Contents
About This Document................................................................................................................ ii
1 Safety Precautions...................................................................................................................1
2 Product Introduction...............................................................................................................4
2.1 Overview.................................................................................................................................................................................... 4
2.2 Structure..................................................................................................................................................................................... 5
2.3 Conguration Principles........................................................................................................................................................ 6
2.4 Application Scenarios............................................................................................................................................................. 8
3 System Maintenance............................................................................................................ 10
3.1 Setting the Physical Layout of the Smart PV Optimizers....................................................................................... 10
3.2 Detecting Optimizer Disconnection................................................................................................................................12
3.3 Rapid Shutdown.................................................................................................................................................................... 13
3.4 Troubleshooting..................................................................................................................................................................... 14
3.5 Replacing an Optimizer...................................................................................................................................................... 15
3.6 Maintaining PV Modules.................................................................................................................................................... 17
4 Technical Specications....................................................................................................... 19
A Acronyms and Abbreviations............................................................................................. 21
MERC Smart PV Optimizer
User Manual Contents
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1 Safety Precautions
General Safety
● Follow the precautions and special safety instructions provided by Huawei
when operating this product. Installation or maintenance personnel must be
well trained, fully understand all safety precautions, and be able to correctly
perform all operations. Huawei will not be liable for any consequences that
may arise due to violations of general safety requirements or safety standards
concerning the usage of the equipment.
● Before performing operations, read through the safety precautions to prevent
accidents. The information provided under the "NOTICE", "CAUTION",
"WARNING", and "DANGER" headings within this manual is not intended to
cover all applicable safety policies, and instead acts as a supplement to the
comprehensive safety information provided.
● Follow local laws and regulations when operating the equipment. The safety
instructions in this document are considered supplementary to local laws and
regulations.
● Do not operate the equipment or cables during thunderstorms.
● Before operating the product, remove any conductors such as jewelry or
watches.
● Use insulated tools during operations.
● Tighten screws using a torque wrench, and mark them in red and blue for
double-check. Installation personnel should mark tightened screws in blue.
Inspection personnel should conrm that the screws are tightened and then
mark them in red. If screws or bolts used to secure the equipment are not
tightened to the required torque, the equipment may fall o the mounting
kits.
● Follow specied procedures during installation and maintenance. Do not
modify the equipment structure or the recommended installation procedures
without prior consent from the manufacturer.
● Install the product in strict accordance with the quick guide.
Declaration
Huawei will not be liable for any consequences in any of the following
circumstances:
MERC Smart PV Optimizer
User Manual 1 Safety Precautions
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● Damage during transportation
● Storage conditions that do not meet the requirements specied in this
document
● Incorrect installation or use
● Installation or use by unqualied personnel
● Failure to follow the operation instructions and safety precautions on the
product and in this document
● Operation beyond the conditions specied in this document
● Operation beyond the specied parameter ranges
● Unauthorized modications to the product or software code or removal of the
product
● Equipment damage due to force majeure (such as lightning, re, and storms)
● Warranty expired and not extended
● Installation or use in environments which are not specied in relevant
international standards
Personnel Requirements
Only qualied electricians are allowed to install, connect cables for, maintain,
troubleshoot, and replace the optimizer.
● Receive professional training.
● Read through this document and understand all safety precautions.
● Get familiar with the safety specications about the electrical system.
● Understand the composition and working principles of the grid-tied PV power
system and local regulations.
● Wear proper personal protective equipment (PPE).
Label Protection
● Do not scrawl or damage any warning labels on the optimizer because these
labels contain important information about safe operation.
● Do not scrawl or damage the nameplate on the back of the optimizer
because it contains important product information.
System Installation
● Ensure that the optimizer is not powered on during the installation.
● Reserve appropriate clearances around the optimizer for installation and heat
dissipation.
Electrical Connections
D ANGER
Before connecting cables, ensure that the optimizer is not damaged. Otherwise,
electric shocks or re may occur.
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User Manual 1 Safety Precautions
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● Ensure that all electrical connections comply with local electrical standards.
● Ensure that the cables used in a grid-tied PV power system are properly
connected and insulated and meet specications.
● The output wiring terminals of the optimizer are not hot-swappable. If the
terminals are hot-swapped, the optimizer may be damaged.
Operation
D ANGER
High voltage from the optimizer in operation may cause an electric shock,
resulting in serious property damage, injury, or death. Strictly comply with the
safety precautions in this document and other related documents when operating
the optimizer.
● Do not touch the optimizer in operation as its surface temperature is high and
may cause burning.
● When operating the equipment, comply with local laws and regulations.
Maintenance and Replacement
D ANGER
High voltage from the optimizer in operation may cause an electric shock,
resulting in serious property damage, injury, or death. Before maintenance, power
o the optimizer and strictly comply with the safety precautions in this document
and other related documents when operating the optimizer.
● Maintain the optimizer with proper understanding of this document and
appropriate tools and testing equipment.
● Place temporary warning signs or erect fences to prevent unauthorized access
to the maintenance site.
● The optimizer can be powered on only after all faults are rectied. Otherwise,
faults may escalate or equipment may be damaged.
● Observe ESD precautions and wear ESD gloves during maintenance.
MERC Smart PV Optimizer
User Manual 1 Safety Precautions
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2 Product Introduction
2.1 Overview
The smart PV optimizer is a DC to DC converter which implements maximum
power point tracking (MPPT) of each PV module to improve the energy yield of
the PV system. It enables module-level shutdown and monitoring, and supports
long-string design.
Functions and Features
● Module-level MPPT: Implements maximum power point tracking of each PV
module to improve the energy yield of the PV system.
● Module-level shutdown: Adjusts the module output voltage to a safe range
when the output is disconnected or the inverter shuts down.
● Module-level monitoring: Monitors the operating status of each PV module.
● Long PV string supported: If all PV modules are congured with optimizers, a
PV string can contain more PV modules than conventional PV strings.
Model
This document involves the following product models:
● MERC-1300W-P
● MERC-1100W-P
Figure 2-1 Model description (MERC-1300W-P optimizer is used as an example)
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User Manual 2 Product Introduction
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Optimizer Model Part No. Rated Input
Power
Input Cable
Length
Output Cable
Length
MERC-1300W-P
(Short input power
cables)
02314APY 1300 W 0.1 m 5.1 m (negative) +0.1
m (positive)
MERC-1300W-P
(Long input power
cables)
02314AQB 1300 W 1.3 m 2.9 m (negative) +0.1
m (positive)
MERC-1100W-P
(Short input power
cables)
02314APY-001 1100 W 0.1 m 5.1 m (negative) +0.1
m (positive)
MERC-1100W-P
(Long input power
cables)
02314AQB-001 1100 W 1.3 m 2.9 m (negative) +0.1
m (positive)
2.2 Structure
Optimizer Ports
Figure 2-2 Ports
(1) Output port (positive) (2) Output port (negative)
(3) Input port (negative) (4) Input port (positive)
MERC Smart PV Optimizer
User Manual 2 Product Introduction
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