SMA Sunny Central 500U User manual

SC500U_GFDI-IUS101311 | 98-4022711 | Version 1.1
US
Change from negative to positive grounding
SUNNY CENTRAL 500U
Installation Guide

SMA America, LLC Legal Restrictions
Installation Guide SC500U_GFDI-IUS101311 3
Copyright © 2010 SMA America,LLC. All rights reserved.
No part of this document may be reproduced, stored in a retrieval system, or transmitted, in any form
or by any means, electronic, mechanical, photographic, magnetic or otherwise, without the prior
written permission of SMA America,LLC.
SMA America,LLC makes no representations, express or implied, 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. Neither SMA America,LLC nor its distributors or dealers shall 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.)
Specifications are subject to change without notice. Every attempt has been made to make this
document complete, accurate and up-to-date. Readers are cautioned, however, that
SMAAmerica,LLC 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.
All trademarks are recognized even if these are not marked separately. Missing designations do not
mean that a product or brand is not a registered trademark.
The Bluetooth® word mark and logos are registered trademarks owned by Bluetooth SIG, Inc. and
any use of such marks by SMA America,LLC is under license.
SMA America, LLC
3801 N. Havana Street
Denver, CO 80239 U.S.A.

Important Safety Instructions SMA America, LLC
4 SC500U_GFDI-IUS101311 Installation Guide
IMPORTANT SAFETY INSTRUCTIONS
SAVE THESE INSTRUCTIONS
This manual contains important instructions for Sunny Central 500U PV inverter, that must be followed
during installation and maintenance of the PV inverter.
The Sunny Central 500U is designed and tested according to international safety requirements, but
as with all electrical and electronic equipment, certain precautions must be observed when installing
and/or operating the Sunny Central 500U. To reduce the risk of personal injury and to ensure the
safe installation and operation of the Sunny Central 500U, you must carefully read and follow all
instructions, cautions and warnings in this installation guide.
Warnings in this document
A warning describes a hazard to equipment or personnel. It calls attention to a procedure or practice,
which, if not correctly performed or adhered to, could result in damage to or destruction of part or all
of the SMA equipment and/or other equipment connected to the SMA equipment or personal injury.
DANGER
DANGER indicates a hazardous situation which, if not avoided, will result in death or
serious injury.
WARNING
WARNING indicates a hazardous situation which, if not avoided, could result in death or
serious injury.
CAUTION
CAUTION indicates a hazardous situation which, if not avoided, could result in minor or
moderate injury.
NOTICE
NOTICE is used to address practices not related to personal injury.

SMA America, LLC Important Safety Instructions
Installation Guide SC500U_GFDI-IUS101311 5
Other symbols in this document
In addition to the safety and hazard symbols described on the previous pages, the following symbol
is also used in this installation guide:
Markings on this product
The following symbols are used as product markings with the following meanings.
Information
This symbol accompanies notes that call attention to supplementary information that you
should know and use to ensure optimal operation of the system.
Warning regarding dangerous voltage
The product works with high voltages. All work on the product must only be performed
as described in it‘s documentation.
Electric arc hazards
The product has large potential between its conductors. Arc flashes can occur through
air when high-voltage current flows. Do not work on the product during operation.
Beware of hot surface
The product can become hot during operation. Do not touch the product during
operation.
Observe the operating instructions
Read the documentation of the product before performing any work. Follow all safety
precautions and instructions as described in the documentation.
AC current
DC current
Earth Ground
UL1741 is the standard applied by Underwriters Laboratories to the Sunny Central
500U to certify that it meets the requirements of the National Electrical Code® and IEEE-
929-2000. IEEE 929-2000 provides recommendations regarding the proper equipment
and functionality necessary to ensure compatible operation when power generation is
connected to the power distribution grid.

General Warnings SMA America, LLC
6 SC500U_GFDI-IUS101311 Installation Guide
General warnings
General warnings
All electrical installations must be done in accordance with the local codes and National
Electrical Code ANSI/NFPA 70.
The Sunny Central 500U contains no user-serviceable parts except for the fans on the
bottom of the enclosure and the filters behind the fans as well as the handle covers on the
sides of the unit. For all repair and maintenance, always return the unit to an authorized
SMA Service Center.
Before installing or using the Sunny Central 500U, read all of the instructions, cautions, and
warnings on the Sunny Central 500U in the installation guides.
Before connecting the Sunny Central 500U to the power distribution grid, contact the local
power distribution grid company. This connection must be made only by qualified
personnel.
Wiring of the Sunny Central 500U must be made by qualified personnel only.

SMA America, LLC Table of Contents
Installation Guide SC500U_GFDI-IUS101311 7
Table of contents
1 Notes on this manual. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
1.1 Target group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
1.2 Syntax. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
2 Safety . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
3 List of materials. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
3.1 Material n/a. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
3.2 Additional material . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
4 Removal of the components . . . . . . . . . . . . . . . . . . . . . . . 12
4.1 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
4.2 Remove transparent covers. . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
4.3 Remove busbars . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
4.4 Remove the wires from current measurement . . . . . . . . . . . . . . 14
5 Mounting the components. . . . . . . . . . . . . . . . . . . . . . . . . 15
5.1 Attach the wires to the current measurement . . . . . . . . . . . . . . 15
5.2 Mount busbars . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
5.3 Attach markings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
5.4 Check all connections. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
5.5 Attach Transparent Cover. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
5.6 Commissioning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

Table of Contents SMA America, LLC
8 SC500U_GFDI-IUS101311 Installation Guide

SMA America, LLC Notes on this manual
Installation Guide SC500U_GFDI-IUS101311 9
1 Notes on this manual
This manual describes the modification of a Sunny Central 500U to GFDI positive grounding. This
manual does not cover any details concerning PV modules. Information concerning the PV modules
is available from the manufacturer of the PV modules.
Keep this manual in a convenient place for future reference.
1.1 Target group
This manual is for qualified personnel only. Qualified personnel have received training and have
demonstrated skills and knowledge in the construction and operation of the device. Qualified
personnel are trained to deal with the dangers and hazards involved in installing electric devices.
1.2 Syntax
In this document the Sunny Central 500U is referred to in the following as Sunny Central.
In this document SMA America Production, LLC is referred to in the following as SMA.

Safety SMA America, LLC
10 SC500U_GFDI-IUS101311 Installation Guide
2 Safety
DANGER
During operation, high voltages are present in the Sunny Central.
Death from electric shock will result.
When working on the Sunny Central, the device must be disconnected form the power
supply and tested for absence of voltage. Be sure to observe the five safety rules for
working on electrical systems.
The five safety rules for working on electrical systems are listed below:
• Switch off the system.
• Ensure that the device cannot be reconnected.
• Wait at least 5 minutes for all internal power supplies to discharge.
• Test for absence of voltage.
• Ground and short-circuit.
•Prevent access to neighboring systems.
CAUTION
Danger of crushing results from falling components.
• Wear personal protective equipment when working on the Sunny Central.

SMA America, LLC List of materials
Installation Guide SC500U_GFDI-IUS101311 11
3 List of materials
Quantity Description Equipment label
1 Busbar in the front
1 Busbar in the back
1 Adhesive label DC+
2 Adhesive label DC‒
2 Marking (equipment label) for the
components
WL+
2 Marking (equipment label) for the
components
WL‒
1 Marking „This unit is grounded at the
positive DC leg.”
1 Marking „max. 600 V DC PV+”
1 Marking „max. 600 V DC PV-”

Removal of the components SMA America, LLC
12 SC500U_GFDI-IUS101311 Installation Guide
4 Removal of the components
4.1 Overview
4.2 Remove transparent covers
Position Description
APosition of the DC+ and DC‒ busbars and the contactor.
1. Remove all screws at the left side of the upper
transparent cover.
2. Remove the transparent cover.
3. Put the screws and the transparent cover aside.
The transparent cover and the screws will be reused
later.
☑ The upper transport cover is removed

SMA America, LLC Removal of the components
Installation Guide SC500U_GFDI-IUS101311 13
4.3 Remove busbars
Between the contactor K3 and busbar WL‒ are two
busbars.
1. Remove the 2 screws of each busbar.
2. Remove the busbars.
3. Put the busbars aside.
The busbars will be reused later.
☑ The busbars between the contactor K3 and busbar WL‒ are removed.
Between the contactor K2 and busbar WL+ are two
busbars.
1. Remove all screws of the busbars.
2. Remove the busbars.
3. Put the busbars aside.
The busbars will not be reused.
☑ The busbars between the contactor K2 and busbar WL+ are removed.
4. Remove the 2 screws on the left side and the 1 screw
on the right side of the lower transparent cover.
5. Remove the transparent cover.
6. Put the screws and the transparent cover aside.
The transparent cover and the screws will be reused
later.
☑ The lower transparent cover is removed.

Removal of the components SMA America, LLC
14 SC500U_GFDI-IUS101311 Installation Guide
4.4 Remove the wires from current measurement
1. Remove the screws that attach the wires from the
current measurement to busbar WL– and busbar
WL+.
2. Remove the wires between the current
measurement and busbar WL– and the wires
between current measurement and busbar WL+ .
☑ The wires of the current measurement are removed.

SMA America, LLC Mounting the components
Installation Guide SC500U_GFDI-IUS101311 15
5 Mounting the components
5.1 Attach the wires to the current measurement
1. Attach the blue wire from the current measurement
to the busbar with DC fuses.
2. Attach the brown cable from the current
measurement to the busbar without DC fuses.
3. Tighten the screws with a torque of 185in-lb.
(21Nm).
☑ The cable to the current measurement is attached.
5.2 Mount busbars
1. Connect the busbar with DC fuses and the
contactors K3:2 and K3:4 with the two provided
busbars.
2. Tighten the screws with a torque of 55ft-lb.
(74Nm).
☑ The busbar between the copper rail with DC fuses and the contactors K3:2 and K3:4 is
installed.
3. Connect the busbar without DC fuses and the
contactors K2:2 and K2:4 with the busbars, which
were previously connected to the contactors K3:2
and K3:4.
4. Tighten the screws with a torque of 55ft-lb.
(74Nm).
☑ The busbars between the busbar without fuses and
the contactors K2:2 and K2:4 are installed.

Mounting the components SMA America, LLC
16 SC500U_GFDI-IUS101311 Installation Guide
5.3 Attach markings
1. Attach the label "DC–" to the busbar with DC fuses.
2. Position label "max. 600V DC PV–" over
"max.600V DC PV+".
3. Remove label "This Unit is grounded at the negative
DC leg."
4. Position label "max. 600V DC PV+" over
"max.600V DC PV–".
5. Attach the label DC+ to the busbar without fuses.
6. Position label "This Unit is grounded at the positive
DC leg." below label "max. 600 V DC PV–".
☑ The markings are attached.
5.4 Check all connections
1. Make sure that all electric and non-electric connections are attached securely.
2. Make sure that all screws are tightened with the specified torques.
5.5 Attach transparent cover
1. Attach the upper transparent cover.
2. Attach the 3 screws at the left side of the upper
transparent cover and tighten them.

SMA America, LLC Mounting the components
Installation Guide SC500U_GFDI-IUS101311 17
5.6 Commissioning
Commission the Sunny Central after modification as described in the installation guide and check the
function of the Sunny Central.
3. Attach the lower transparent cover.
4. Attach the 2 screws on the left side and the 1 screw
on the right side of the lower transparent cover and
tighten them.
☑ The transparent covers are attached.

4.""NFSJDB--$
XXXSMAANFSJDBDPN