Ampt V425 User manual

Ampt String Optimizer
V600-12-12
Installation Manual
57070013-1 H
©2021 Ampt LLC

Copyright 2021 Ampt LLC.
All rights reserved.
2
V600-12 String Optimizer Platform
Installation Manual: 57070013-1 H

Copyright 2021 Ampt LLC.
All rights reserved.
3
V600-12 String Optimizer Platform
Installation Manual: 57070013-1 H
Copyright 2021 Ampt LLC. All rights reserved. No part of this document may be reproduced,
retransmitted, or copied in any form without the expressed and written permission of Ampt.
This document contains information needed to install and commission an Ampt optimizer
(including Smart String Technology®optimizers, String Stretch®optimizers, Ampt Mode®
optimizers, String View®optimizers, V-match®optimizers, and Direct-to-Battery®optimizers)
within a photovoltaic (PV) installation. The result? Energy realized®.
All Ampt trademarks are the property of Ampt, LLC. All trademarks are recognized even if they
are not marked separately. Visit www.ampt.com/trademarks for a list of Ampt trademarks. Any
unauthorized use of Ampt trademarks is prohibited. All other trademarks are the property of
their respective owners.
U.S. and international patents apply to this product. For details visit: www.ampt.com/patents.
Read This First
To help avoid problems during the system installation, familiarize yourself in advance with the
installation process by reading this entire document before starting the installation.
Risk of electric shock, do not remove covers. No user serviceable parts inside.
Refer servicing to qualified service personnel. When the photovoltaic array is
exposed to light, it supplies a dc voltage to this equipment.
Le risqué de décharge électirque n’enlènvent pas la couverture. Aucunes pieces
utiles d’utilisateur à l’intérieur. Référez-vous l’entretien au personnel de service
qualifiè. Quand la range photovoltaïque est exposée à la lumière. Il fournit une
tension CC à cet équipement.
Hot surfaces –to reduce the risk of burns –do not touch.
Les surfaces chaudes - pour réduire le risque de brûlures - ne se touchent pas.

Copyright 2021 Ampt LLC.
All rights reserved.
4
V600-12 String Optimizer Platform
Installation Manual: 57070013-1 H
Important Safety Instructions
This manual contains important instructions for Ampt optimizers that shall be followed during
installation and maintenance. The optimizer has been designed and tested according to
international safety requirements, but requires certain precautions are observed when
installing and/or operating the optimizer. To reduce the risk of personal injury and to ensure
the safe installation and operation of the optimizer, please be sure you carefully read and
follow all instructions and safety messages in this manual.
SAVE THESE INSTRUCTIONS
Safety Message Types
The following messaging is used to identify a hazard to equipment or personnel:
DANGER
Indicates a hazardous situation which, if not avoided, will result in death or
serious injury.
WARNING
Indicates a hazardous situation which, if not avoided, could result in death or
serious injury.
CAUTION
Indicates a hazardous situation which, if not avoided, could result in minor or
moderate injury.
NOTICE
Indicates information considered important but not hazard, or personal injury,
related - for example, property damage.

Copyright 2021 Ampt LLC.
All rights reserved.
5
V600-12 String Optimizer Platform
Installation Manual: 57070013-1 H
General Safety
Installation and maintenance should be performed only by qualified persons. Installers and
maintenance personnel assume the risk of all injury that might occur during installation or
maintenance including, without limitation, the risk of electric shock. Follow your safety
procedures and protocols.
All electrical installations must be done in accordance with the local and National Electrical
Code ANSI/NFPA 70; Canadian Electrical Code, Part I; or the applicable standards, codes, and
regulations for your region.
Failure to follow this manual will void warranty.
The Ampt product contains no user-serviceable parts. All repairs and maintenance should be
handled in accordance with the instructions and terms contained in the product warranty.
Before installing or using the Ampt optimizer, read all of the instructions and safety messages
on the optimizer and in this manual. Follow the safety precautions for this product as well as
the other components in the PV system.
PV modules produce electrical energy when exposed to light and thus can create an electrical
shock hazard. Wiring of the PV modules should only be performed by qualified personnel.
NOTICE
Opening the optimizers, performing any other service to the optimizers, or using
the optimizers in a way that is not specified by the manufacturer voids warranty.

Copyright 2021 Ampt LLC.
All rights reserved.
6
V600-12 String Optimizer Platform
Installation Manual: 57070013-1 H
Disclaimer of Liability
Ampt makes no representations, expressed or implied, that with respect to this documentation
or any of the equipment and/or software it may describe, including (with no limitation) any
implied warranties of utility, merchantability, or fitness for any particular purpose. All such
warranties are expressly disclaimed. Ampt shall not be liable for any indirect, incidental, or
consequential damages under any circumstances. (The exclusion of implied warranties may not
apply in all cases under some statutes, and thus the above exclusion may not apply.)
The following information is subject to change without notice, even though every attempt has
been made to make this document complete, accurate and up-to-date. Readers are cautioned,
however, that Ampt reserves the right to make changes without notice and shall not be
responsible for any damages, including indirect, incidental or consequential damages, caused
by reliance on the material presented, including, but not limited to, omissions, typographical
errors, arithmetical errors or listing errors in the content material.
WARNING
Any use of the Ampt String Optimizer that is not expressly authorized in this
manual or associated documentation is expressly prohibited by Ampt. Ampt
disclaims any responsibility or liability for such prohibited use.

Copyright 2021 Ampt LLC.
All rights reserved.
7
V600-12 String Optimizer Platform
Installation Manual: 57070013-1 H
Before You Begin
Handling and Storage
•Store optimizers in a clean, dry area that is protected from weather exposure and
pooling water (-30 to 80°C. Relative humidity < 80%).
•Leave the product in its original packing box until you are ready to install.
•Do NOT stack pallets.
•Do NOT lift, carry, or otherwise handle the optimizers by their connectors.
•Leave connector caps in place until the optimizers are ready to be connected to protect
the optimizer from water and debris ingress.
•Do NOT transport optimizers that are removed from original packaging. If the original
packaging is no longer available, use a similar box to protect the connectors and heat
sink fins.
Quick Reference and Best Practices
NOTICE
The last page of this manual has a quick reference sheet for making electrical
connections as well as a list of best practices. This information is meant to be
used as a reference on the job site to ensure the electrical connection order and
to avoid damage to the device after the installer has read this manual.
Using Optional Wireless Communication
NOTICE
If the String Optimizers are being used with optional wireless communication,
then refer to the Ampt Communication Unit (Ampt CU) manual for important
requirements related to the String Optimizer installation.

Copyright 2021 Ampt LLC.
All rights reserved.
9
V600-12 String Optimizer Platform
Installation Manual: 57070013-1 H
Table of Contents
Read This First ....................................................................................................................................3
Important Safety Instructions........................................................................................................................4
Safety Message Types ...................................................................................................................................4
General Safety...............................................................................................................................................5
Disclaimer of Liability ....................................................................................................................................6
Before You Begin ................................................................................................................................7
Handling and Storage....................................................................................................................................7
Quick Reference and Best Practices...............................................................................................................7
Using Optional Wireless Communication .......................................................................................................7
Chapter 1: Product Overview ...................................................................................................11
Dimensional Drawings......................................................................................................................12
Physical Overview.............................................................................................................................13
Bar Code Label..................................................................................................................................13
Chapter 2: Understanding Electrical Configurations.................................................................15
PV Array Configurations ...................................................................................................................15
Ungrounded PV Arrays ................................................................................................................................ 15
Grounded PV Arrays (positive or negative)................................................................................................... 15
Input Criteria ....................................................................................................................................16
Acceptable Input Configurations..................................................................................................................16
Acceptable Input Configurations Between Parallel Optimizers .....................................................................17
Fuses................................................................................................................................................. 17
DC-coupled Storage..........................................................................................................................17
Inter-row Shading Wiring Example...................................................................................................18
Chapter 3: Installing the String Optimizer ................................................................................19
Getting Started.................................................................................................................................19
Parts and Tools Needed............................................................................................................................... 19
Mounting and Grounding the String Optimizer ................................................................................ 20
Mounting Considerations ............................................................................................................................20
Steps........................................................................................................................................................... 21
Understanding Connector Polarity ...................................................................................................22
Making Electrical Connections..........................................................................................................23
Connection/Disconnection Order Matters ................................................................................................... 24
Connecting the Inputs ................................................................................................................................. 24
Connecting the Output................................................................................................................................ 27
Disconnecting the Output and Inputs...............................................................................................28
Parts and Tools Needed...............................................................................................................................28

Copyright 2021 Ampt LLC.
All rights reserved.
10
V600-12 String Optimizer Platform
Installation Manual: 57070013-1 H
Steps........................................................................................................................................................... 29
Appendix ..................................................................................................................................31
Compliance.......................................................................................................................................31
Model Numbering System........................................................................................................................... 31
Markings..................................................................................................................................................... 31
FCC Compliance .......................................................................................................................................... 32
RSS-GEN......................................................................................................................................................32
Avis IC......................................................................................................................................................... 32
RSS-GEN......................................................................................................................................................32
Specifications....................................................................................................................................33
12 A models (V425 - V600) ..........................................................................................................................33
Reference: Electrical Connection Order............................................................................................35
Handling and Storage Best Practices............................................................................................................ 36
Mounting Best Practices.............................................................................................................................. 36
Electrical Connections Best Practices........................................................................................................... 36
Ampt Support Contacts ............................................................................................................................... 36

Copyright 2021 Ampt LLC.
All rights reserved.
11
V600-12 String Optimizer Platform
Installation Manual: 57070013-1 H
Chapter 1: Product Overview
Ampt String Optimizers are DC/DC converters with multiple features that lower the cost and
improve the performance of new and existing PV systems and energy storage systems.
•Dual MPPT per optimizer - Ampt String Optimizers put maximum power point tracking on each of its
two input strings of PV modules. This mitigates or eliminates mismatch losses to deliver more energy
under changing environmental and system conditions over the lifetime of the power plant.
•High Fixed-Voltage Bus (HFVB) –Ampt’s advanced DC power management technology allows for
HFVB system designs which turn the variable voltage of the PV array into a fixed and predictable DC
bus voltage to achieve system-level economic advantages.
•Ampt Mode–Inverters with Ampt Modeoperate in a fixed or narrow input voltage range that is
closer to the maximum system voltage. This allows the inverter to deliver a higher AC output voltage
at the same current which raises the rated output power of the inverter to lower the inverter's cost
per watt.
•String Stretch® –Ampt’s patented String Stretch® technology puts voltage and current limits on the
output of each optimizer which doubles the number of modules per string and allows for smaller
conductor sizing per kilowatt delivered to save up to 50% on electrical BOS costs.
•Direct-to-Converter –For DC-coupled energy storage systems, Ampt String Optimizers include Direct-
to-Converter technology which allows the DC bus to operate at a higher fixed voltage, so the
converter only needs to buck when charging and boost when discharging. This simplified operation
reduces battery converter costs by up to 50% with less circuitry and a higher power density.
•High DC/AC –Ampt’s unique combination of output current limits and a higher DC bus voltage allows
PV system designers to achieve optimal DC/AC ratios (up to 3:1). With Ampt, system owners can
expand the DC power on existing systems without replacing inverters, combiners, or cables; optimize
inverter utilization on new systems to lower the cost per watt; and lower capex while increasing
storage durations on systems with DC-coupled energy storage.
•V-match–Ampt’s patented V-matchtechnology allows the output of our optimizers to match the
DC bus voltage set by the inverter or battery converter while delivering full available power from the
PV modules. This uniquely allows PV arrays with Ampt to automatically adapt to legacy or future
power equipment to repower existing systems, upgrade inverters, mix new and legacy PV modules,
deploy optimized DC-coupled storage systems, and other applications.
•Full Tracker Fit –Ampt optimizers overcome string-voltage sizing constraints to fit more modules on a
tracker than systems without Ampt. Increasing the number of modules per tracker allows system
designers to fully use the tracker’s mechanical capacity and lower tracker cost per watt.
•Wireless Communication –Ampt String Optimizers incorporate optional wireless communication to
provide string-level data that is highly accurate, synchronous, and scalable to improve O&M, as well as
enhanced controls for storage applications.
For more information on Ampt’s product features and applications, visit www.ampt.com.

Copyright 2021 Ampt LLC.
All rights reserved.
12
V600-12 String Optimizer Platform
Installation Manual: 57070013-1 H
Dimensional Drawings
The dimensions for the String Optimizer shown below are in millimeters and inches.
Figure 1: Dimensional drawings
80
3.15”
37.5
1.48”
220
8.66”
215
8.46”
~259
10.19”
75
2.95”
75
2.95”
208
8.19”

Copyright 2021 Ampt LLC.
All rights reserved.
13
V600-12 String Optimizer Platform
Installation Manual: 57070013-1 H
Physical Overview
Figure 2: Physical overview of the string optimizer
Bar Code Label
The image below shows the bar code label with model and serial numbers. Do NOT remove this
label. Removing any label from the optimizer voids warranty.
Figure 3: Bar code tag with the model and serial numbers
Input A connectors
Input B connectors
Output connectors
Grounding stud
(10-32) x 2
Bar code label
+-
+-
+-
Mounting holes
(6.5 mm) x 6
Antenna for optional
wireless communication

Copyright 2021 Ampt LLC.
All rights reserved.
15
V600-12 String Optimizer Platform
Installation Manual: 57070013-1 H
Chapter 2:
Understanding Electrical Configurations
This chapter explains the installation requirements and considerations that ensure proper
operation of the String Optimizer.
NOTICE
The inputs of the optimizer are not intended for connection to a battery or any
other type of DC source except PV modules.
PV Array Configurations
String Optimizers can be installed in ungrounded and resistively grounded PV systems.
Ungrounded PV Arrays
Figure 4: Electrical connections for an ungrounded PV array
Grounded PV Arrays (positive or negative)
Figure 5: Electrical connections for a grounded PV array

Copyright 2021 Ampt LLC.
All rights reserved.
16
V600-12 String Optimizer Platform
Installation Manual: 57070013-1 H
Input Criteria
In the figures that follow, the number of modules connected in series is representative only.
Follow Ampt’s design guidelines to determine the number of modules for each input.
Acceptable Input Configurations
The following criteria must be met:
1. The voltage for each input must be between the minimum startup voltage of 210 volts
and the maximum input voltage of 585 volts.
a. 210 V ≤Voc-cold-inA ≤ 585 V and 210 V ≤Voc-cold-inB ≤ 585 V
2. The current for each input must be less than the maximum input current (11.5 A).
a. Imp@STC-inA ≤ 11.5 A and Imp@STC-inB ≤ 11.5 A
If the voltage or power between the two inputs is not the same, then follow the additional
criteria below:
3. The voltage on Input A should be less than or equal to the voltage on Input B.
a. Voc-cold-inA ≤ Voc-cold-inB
4. The difference in power between the two inputs should be less than 60%.
Figure 6: The number of modules on each input can be the same as illustrated by String Optimizer 1, or input B can have more
modules than input A so long as the acceptable input criteria is met as shown by String Optimizer 2.
A = B
Voc-cold-inA ≤ Voc-cold-inB
and
Power difference
between InA and InB
is less than 60%

Copyright 2021 Ampt LLC.
All rights reserved.
17
V600-12 String Optimizer Platform
Installation Manual: 57070013-1 H
Acceptable Input Configurations Between Parallel Optimizers
The number of modules on each input between parallel optimizers can vary within an array so
long as they meet the criteria described in the Acceptable Input Configurations section and are
within the minimum and maximum limits determined by Ampt’s design guidelines. An example
is shown below.
Figure 7: The number of modules per input between parallel optimizers can vary so long as they follow the acceptable input
configuration criteria and Ampt’s design guidelines.
Fuses
CAUTION
Over-current protection devices and conductors shall be sized in accordance with
the National Electrical Code (ANSI/NFPA 70); Canadian Electrical Code, Part I;
or the applicable standards, codes, and regulations for your region.
The output current limit of the Ampt String Optimizer eliminates the need for the 1.25
multiplication factor for over-sun conditions when calculating ampacity. The 1.25 multiplier for
continuous use is still required.
Optimizer Max Output Current (A)
Minimum Fuse Size (A)
12
15
DC-coupled Storage
When used in DC-coupled storage applications, the optimizer does not function as a blocking
diode.
Optimizer output
strings to combiner

Copyright 2021 Ampt LLC.
All rights reserved.
18
V600-12 String Optimizer Platform
Installation Manual: 57070013-1 H
Inter-row Shading Wiring Example
When inter-row shading is expected, the best practice is to wire the modules on the two inputs
of the Ampt String Optimizer to be on the same row as shown below.
Figure 8: Wiring example when inter-row shading is expected
Ampt String Optimizer
not to scale
to combiner
to combiner

Copyright 2021 Ampt LLC.
All rights reserved.
19
V600-12 String Optimizer Platform
Installation Manual: 57070013-1 H
Chapter 3:
Installing the String Optimizer
Getting Started
This chapter addresses the proper mounting and installation of the Ampt String Optimizer. Read
the entire chapter before starting the procedures and then conduct each task in the order
given.
Parts and Tools Needed
•The mounting hardware and tools vary by the type of PV module mounting rail.
•Voltmeter (rated for the PV system’s maximum system voltage) with DC current clamp.
•Amphenol Sealing Caps –H4 or UTX
H4 Sealing Cap (for female)
H4PF
UTX Sealing Cap (for female)
UTXF
H4 Sealing Cap (for male)
H4PM
UTX Sealing Cap (for male)
UTXM

Copyright 2021 Ampt LLC.
All rights reserved.
20
V600-12 String Optimizer Platform
Installation Manual: 57070013-1 H
Mounting and Grounding the String Optimizer
Mounting Considerations
•Do NOT mount optimizers with connectors facing upwards.
•Leave space between mounted optimizers to allow for air circulation and cooling.
•Ensure sufficient spacing so that maintenance personnel can read the optimizer
faceplate, safety icons, serial number, model number, and bar code label.
•Keep optimizer free from pooling water.
•Do NOT mount optimizers directly to a solar module frame.
•Do NOT drill into optimizer frame to expand mounting holes.
•If using wireless communication:
oOptimizers have an antenna on the opposite side of the connectors. Keep the
antenna clear from obstructions - including cables, mounting hardware, and PV
modules, to allow radio waves to and from the Ampt Communication Unit (CU).
oLine of sight from the optimizer to the Ampt CU is recommended.
oSee the Ampt CU manual for more information.
•When possible, mount optimizer in a location protected from the elements.
•Leave connector sealing caps in place until the optimizers are ready to be connected to
the PV string.
WARNING
Read the warning statements below:
Installation and maintenance should be performed only by qualified persons.
Installers and maintenance personnel assume the risk of all injury that might
occur during installation or maintenance including, without limitation, the risk of
electric shock. Follow your safety procedures and protocols.
All electrical installations must be done in accordance with the local and National
Electrical Code ANSI/NFPA 70; Canadian Electrical Code, Part I; or the
applicable standards, codes, and regulations for your region.
The Ampt optimizer is to be installed so that it is not expected to be contacted by
persons.
CAUTION
Keep connectors dry and clean. Do not install Ampt String Optimizers in a
location where they might be immersed in water.
NOTICE
Read the notice statements below: