disconnect unit for sunny central 250u_500u_500he‑us and sunny central cp - unpacking...

DISU_SCUS-AP-eng-IUS110911 | 98-4051011 | Version 1.1 CA US

AC/DC Disconnect UnitDisconnect Unit for Sunny Central 250U/500U/500HE‑US and Sunny Central CPUnpacking

SMA America, LLC Legal Restrictions

Unpacking DISU_SCUS-AP-eng-IUS110911 3

Copyright © 2011 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.Neither SMA America, LLC nor SMA Solar Technology Canada Inc. makes 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 nor SMA Solar Technology Canada Inc. 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 and SMA Solar Technology Canada Inc. reserve 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 and SMA Solar Technology Canada Inc. is under license.

SMA America, LLC3801 N. Havana Street

Denver, CO 80239 U.S.A.

SMA Solar Technology Canada Inc.2425 Matheson Blvd. E, 8th Floor

Mississauga, ON L4W 5K5, Canada

Important Safety Instructions SMA America, LLC

4 DISU_SCUS-AP-eng-IUS110911 Unpacking

IMPORTANT SAFETY INSTRUCTIONSSAVE THESE INSTRUCTIONSThis manual contains important instructions for the Disconnect Unit for Sunny Central 250U/500U/500HE-US and Sunny Central CP, that must be followed during installation and maintenance of the pv inverter.The Disconnect Unit for Sunny Central 250U/500U/500HE-US and Sunny Central CP 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 Disconnect Unit for Disconnect Unit for Sunny Central 250U/500U/500HE-US and Sunny Central CP. To reduce the risk of personal injury and to ensure the safe installation and operation of the Disconnect Unit for Sunny Central 250U/500U/500HE-US and Sunny Central CP, you must carefully read and follow all instructions, cautions and warnings in this technical description.

Warnings in this documentA 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 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 is used to address practices not related to personal injury.

SMA America, LLC Important Safety Instructions


Other symbols in this documentIn addition to the safety and hazard symbols described on the previous pages, the following symbol is also used in this technical description:

Markings on this productThe following symbols are used as product markings with the following meanings.

InformationThis 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 voltageThe product works with high voltages. All work on the product must only be performed as described in the documentation of the product.Electric arc hazardsThe product has large electrical potential differences 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 surfaceThe product can become hot during operation. Do not touch the product during operation.Observe the operating instructionsRead the documentation of the product before working on it. Follow all safety precautions and instructions as described in the documentation.UL1741 is the standard applied by Underwriters Laboratories to the Disconnect Unit for Sunny Central 250U/500U/500HE-US and Sunny Central CP to certify that it meets the requirements of the National Electrical Code®, the Canadian Electrical Code® CSA C22.1 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 utility grid.

General Warnings SMA America, LLC


General warnings

All electrical installations must be done in accordance with the local and National Electrical Code® ANSI/NFPA 70 or the Canadian Electrical Code® CSA C22.1. Before installing or using the Disconnect Unit for Sunny Central 250U/500U/500HE-US and Sunny Central CP, read all of the instructions, cautions, and warnings on the Disconnect Unit for Sunny Central 250U/500U/500HE-US and Sunny Central CP in this technical description.Before connecting the Disconnect Unit for Sunny Central 250U/500U/500HE-US and Sunny Central CP to the power distribution grid, contact the local power distribution grid company. This connection must be made only by qualified personnel.Wiring of the Disconnect Unit for Sunny Central 250U/500U/500HE-US and Sunny Central CP must be made by qualified personnel only.

SMA America, LLC Table of Contents


Table of Contents1 Information on this Manual. . . . . . . . . . . . . . . . . . . . . . . . . 92 Scope of Supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103 Storage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114 Transport Packaging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 124.1 Transport Packaging and Center of Gravity . . . . . . . . . . . . . . . 124.2 Symbols on the Transport Packaging . . . . . . . . . . . . . . . . . . . . 144.3 Technical Data for the Transport Packaging . . . . . . . . . . . . . . . 145 Transporting the Packaged Disconnect Unit . . . . . . . . . . 156 Unpacking the Disconnect Unit . . . . . . . . . . . . . . . . . . . . . 166.1 Removing the Film . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 166.2 Removing the Lashing Straps . . . . . . . . . . . . . . . . . . . . . . . . . . 176.3 Removing the Clamping Bands. . . . . . . . . . . . . . . . . . . . . . . . . 186.4 Removing the Box Components . . . . . . . . . . . . . . . . . . . . . . . . 187 Transporting the Disconnect Unit Without Packaging . . 217.1 Transporting the Disconnect Unit Using a Crane . . . . . . . . . . . 217.2 Transporting the Disconnect Unit Using a Forklift Truck . . . . . . 228 Preparing the Disconnect Unit for Installation . . . . . . . . . 258.1 Opening the Disconnect Unit . . . . . . . . . . . . . . . . . . . . . . . . . . 258.2 Mounting the Lid . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 288.3 Closing the Disconnect Unit . . . . . . . . . . . . . . . . . . . . . . . . . . . 299 Contact . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

SMA America, LLC


SMA America, LLC Information on this Manual


1 Information on this ManualValidityThis manual applies to the Disconnect Unit of the following device types:

• Sunny Central 250U• Sunny Central 500U• Sunny Central 500HE-US• Sunny Central 500HE-CA• Sunny Central CP

Target GroupThis manual is intended for skilled workers. Only qualified personnel are allowed to perform the tasks set forth in this manual.

Definition of the Target GroupSkilled workers have been trained and briefed adequately and have the capability and knowledge to install and operate the equipment. Skilled workers are trained to deal with the dangers and hazards involved in transporting and assembling the equipment.

Additional InformationKeep all manuals for the Disconnect Unit and for the installed components together with the system documentation. All documents must be available at all times. The documents listed below are included in the scope of delivery for your Disconnect Unit.The following information is contained in these documents:

Additional information is available at www.SMA-America.com.

NomenclatureIn this document, the Disconnect Unit for Sunny Central 250U/500U/500HE-US/CA and Sunny Central CP are hereinafter referred to as the Disconnect Unit.In this document, SMA America Production, LLC, and SMA Solar Technology Canada Inc. are hereinafter referred to as SMA.

Information Document TypeSetup and installation of the Disconnect Unit Installation GuideUnpacking, transporting and preparing the Disconnect Unit Unpacking manualDisconnect Unit circuit diagram Circuit diagrams

Scope of Supply SMA America, LLC


2 Scope of SupplyThe Disconnect Unit is supplied in a box. This box contains the Disconnect Unit, the lid for the Disconnect Unit and an accessories kit. Check the scope of supply for completeness and for any external damage. Please contact your dealer if the scope of supply is not complete or you find any damage.The scope of supply is listed in this chapter.

Accessories KitThe accessories kit is packed in a box. The box is called Accessories.

Supplied ComponentsNumber Description

1 TX screwdriver T251 TX screwdriver T301 Warning sticker SC-US positive/negative grounding1 Disconnect Unit Sunny Central US Installation Guide1 Circuit diagram for DU-SC-US, EN

SMA America, LLC Storage


3 Storage

Damage to property caused by penetrating moisture!Damage to electrical component parts caused by penetrating moisture.

• The Disconnect Unit must be closed during storage.• Storage for six months or more permissible in dry locations only.• Do not store the Disconnect Unit in the transport packaging for longer than six months.

Damage to property caused by improper storage!Improper storage conditions may damage the Disconnect Unit.

• The foundation must be suitable for the weight of the Disconnect Unit of 1 477 lbs. (685 kg). The foundation may only deviate from a level of 0.25 %.

• Only store the Disconnect Unit at temperatures between − 40 °F ... +140 °F ( − 40 °C ... +60 °C).

Ensure function in the case of longer storage timesIf the Disconnect Unit is stored for longer than one year, check the functionality of the Disconnect Unit every 12 months. Move all switches to the "ON" position and the "OFF" position ten times. This guarantees the function of the switches.

Transport Packaging SMA America, LLC


4 Transport Packaging4.1 Transport Packaging and Center of GravityThe front and back walls of the transport packaging are marked with a symbol for the center of gravity. The center of gravity of the transport packaging is not in the middle. The symbol for the center of gravity shows the position of the centre of gravity.

Figure 1: Center of gravity indication

Center of Gravity of the Disconnect Unit for Sunny Central 250U/500UAll dimensions for the center of gravity indication relate to the bottom left corner of the back wall.Horizontal (B) 3 5⁄16 ft. (1 013 mm)Vertical (A) 3 3⁄16 ft. (971 mm)Depth (C) 1 7⁄8 ft. (570 mm)

A

B C

SMA America, LLC Transport Packaging


Center of Gravity of the Disconnect Unit for Sunny Central CP/500HE-US without AC Switch:All dimensions for the center of gravity indication relate to the bottom left corner of the back wall.

Center of Gravity of the Disconnect Unit for Sunny Central CP/500HE-US with AC Switch:All dimensions for the center of gravity indication relate to the bottom left corner of the back wall.

Horizontal (B) 3 5⁄16 ft. (1 010 mm)Vertical (A) 3 3⁄4 ft. (1 151 mm)Depth (C) 1 5⁄8 ft. (494 mm)

Horizontal (B) 3 23⁄64 ft. (1 023 mm)Vertical (A) 3 43⁄64 ft. (1 119mm)Depth (C) 1 ft. 9 1⁄2 in. (544 mm)

Transport Packaging SMA America, LLC


4.2 Symbols on the Transport PackagingThe following symbols are applied to the transport packaging:

4.3 Technical Data for the Transport PackagingTechnical Data for the Disconnect Unit for Sunny Central 250U/500U

Technical Data for the Disconnect Unit for Sunny Central CP/500HE-US

Symbol ExplanationTransport the transport packaging with this side up.

The contents of the transport packaging are fragile.

Do not use sharp tools when opening the transport packaging.

Do not place anything on top of the transport packaging.

Center of gravity of the transport packaging.

Weight (approximate) 1 150 lbs. (522 kg)Width x height x depth 6 ft. x 6 1⁄2 ft. x 3 ft. 8 21⁄64 in. (1 829 mm x 1 981 mm x 1 130 mm)

Weight (approximate) 1 510 lbs. (685 kg)Width x height x depth 6 ft. x 7 in. x 3 ft. 4 in. x 8 21⁄64 in. (1 829 mm x 2 235 mm x 1 130 mm)

SMA America, LLC Transporting the Packaged Disconnect Unit


5 Transporting the Packaged Disconnect UnitYou can transport the packaged Disconnect Unit using a forklift truck.

1. Drive forklift truck under the transport packaging at the center of gravity marking.2. Secure the package against tipping, for example using lashing straps.3. Raise the package slightly.4. Transport the package.

Danger of crushing caused by tipping package!If insufficiently secured, the package can fall off the pallet.

• Only transport the package as described in this manual.• Take note of the centre of gravity marking on the transport packaging.• Means of transport must be designed for the weight of the package.• Do not tip package over during transport.• Transport the package only if sufficiently secured.• Keep a safe distance from the package at all times during transport.

Unpacking the Disconnect Unit SMA America, LLC


6 Unpacking the Disconnect Unit6.1 Removing the FilmThe Disconnect Unit is packed using a protective film. This film is affixed to the pallet. Remove this film as described in this section.

1. Cut through film close to the pallet.

2. Pull film off the Disconnect Unit upward.

Damage to property caused by sharp objects!When cutting through the film with a sharp object you could damage the enclosure of the Disconnect Unit.

• Only cut through the film close to the pallet.• Observe the correct distance from the enclosure.

SMA America, LLC Unpacking the Disconnect Unit


6.2 Removing the Lashing StrapsThe Disconnect Unit box is secured to the pallet using lashing straps to prevent tipping during transport.

1. Cut through lashing straps with a knife.2. Remove the lashing straps.

Risk of being cut by rebounding lashing straps!The lashing straps are under tension and spring back when removed.

• Wear personal protective equipment.• Keep a safe distance from the lashing straps.

Danger of crushing caused by tipping package!If insufficiently secured, the package can fall off the pallet.

• Take note of the centre of gravity marking on the transport packaging.• All means of transport used must be designed for the weight of the package of 1 510 lbs.

(685 kg).• Do not tip package over during transport.• Do not transport the package unless sufficiently secured.• Keep a safe distance from the package at all times during transport.



6.3 Removing the Clamping BandsThe individual box components of the Disconnect Unit are affixed with clamping bands.

1. Cut through clamping bands with a knife.2. Remove the clamping bands.

6.4 Removing the Box Components1. Remove lid of box.

Risk of being cut by rebounding clamping bands!The clamping bands are under tension and spring back when removed.

• Wear personal protective equipment.• Keep a safe distance from the clamping bands.

SMA America, LLC Unpacking the Disconnect Unit


2. Remove wooden frame and squared timber.

3. Open the clamping fastener by pulling the strap on the left-hand side.

4. Remove clamping fastener from box.

5. Remove walls of the box.

– Remove front wall of the box.

– Remove back wall of the box.



6. Remove boxes from the side. The lid and the accessories kit are found in the lower box. The upper box is packaging material.

7. Remove the box cover.

8. Unpack lid.9. Remove accessories kit.

10. Open accessories kit.

SMA America, LLC Transporting the Disconnect Unit Without Packaging


7 Transporting the Disconnect Unit Without Packaging7.1 Transporting the Disconnect Unit Using a Crane

11. Position the crane hook with crane cables in the center above the Disconnect Unit.

12. Connect the load hook of the crane cables to all four crane eyes of the Disconnect Unit.

13. Raise the crane hook slowly until the crane cables are tensed.

14. Ensure that all crane cables and load hooks are attached correctly.15. Raise the Disconnect Unit slightly.16. Transport the Disconnect Unit to the installation site.

Danger of crushing if raised or hovering Disconnect Unit tips over, falls or swings!If the Disconnect Unit is raised and transported without due care or too quickly it may tip over or fall.

• Transport the Disconnect Unit as close to the ground as possible at all times.• Use all suspension points for transportation.• Avoid making fast and jerky movements with the crane.• Keep a safe distance from the Disconnect Unit at all times during transport.• All means of transport used must be designed for the weight of the Disconnect Unit of

1 510 lbs. (685 kg).

Transporting the Disconnect Unit Without Packaging SMA America, LLC


7.2 Transporting the Disconnect Unit Using a Forklift TruckRemoving the Kick Plates of the Disconnect UnitUnscrew the kick plates to transport the Disconnect Unit using a forklift truck.There are two kick plates at the front and two kick plates at the back of the Disconnect Unit.

1. Remove all eight screws of the two front kick plates.

2. Remove both front kick plates.

3. Remove all eight screws of the two rear kick plates.

SMA America, LLC Transporting the Disconnect Unit Without Packaging


4. Remove both rear kick plates.

Transporting the Disconnect Unit

1. Drive the forklift truck under the Disconnect Unit at the front or back.

2. Secure Disconnect Unit against tipping, for example using lashing straps.3. Raise the Disconnect Unit slightly.4. Transport the Disconnect Unit to the installation site.

Danger of crushing caused by tipping of the Disconnect Unit!If insufficiently secured, the Disconnect Unit can tip over.

• Only transport the Disconnect Unit as described in this manual.• Observe the center of gravity of the Disconnect Unit.• All means of transport used must be designed for the weight of the Disconnect Unit of

1 510 lbs. (685 kg).• Do not tip Disconnect Unit over during transport.• Transport the Disconnect Unit only if sufficiently secured.• Keep a safe distance from the Disconnect Unit at all times during transport.

Transporting the Disconnect Unit Without Packaging SMA America, LLC


Install the Kick Plates of the Disconnect UnitAfter transporting the Disconnect Unit, replace the kick plates.

1. Align both front kick plates to the Disconnect Unit and place all eight screws in the holes.

2. Tighten all eight screws of the two front kick plates with a torque of 44 in-lbs. (5 Nm).

3. Align both rear kick plates to the Disconnect Unit and place all eight screws in the holes.

4. Tighten all eight screws of the two rear kick plates with a torque of 44 in-lbs. (5 Nm).

SMA America, LLC Preparing the Disconnect Unit for Installation


8 Preparing the Disconnect Unit for Installation8.1 Opening the Disconnect Unit

1. Turn all switches of the Disconnect Unit to the right into the "On" position. Push or pull the switches hard to move them.

2. Release the three screws on the handles on the left-hand side of the front plate.

Note the grounding strap on the front plateAt the bottom left corner of the front plate, a grounding strap is fitted and connected to the Disconnect Unit. Do not damage the grounding strap when opening the Disconnect Unit.

Danger of crushing caused by heavy front plate!When removing the front plate, there is a danger of crushing between the Disconnect Unit and the front plate.

• Note the weight of the front plate of 110 lbs. (50 kg).• Move the front plate of the Disconnect Unit with at least two persons.• Ensure that one person is holding the front plate of the enclosure at all times when the other

person is working on it.• Wear personal protective equipment.

Off

On

Preparing the Disconnect Unit for Installation SMA America, LLC


3. Turn all switches on the Disconnect Unit to the left into the "Off" position. Push or pull the switches hard to move them.

4. Release all screws with the exception of the screws in the four corners of the front plate.

5. Hold the front plate of the Disconnect Unit and release the last four screws.

6. Pull the bottom edge of the front plate of the enclosure approximately 6 in. (150 mm) to the front.

On

Off



7. Pull the front plate of the enclosure upwards and unhook.

8. Pull the front plate forwards by around 8 in. (200 mm) and hold with two hands.

9. Unscrew grounding strap at the bottom left corner of the front plate.

10. Remove front plate.



8.2 Mounting the Lid

1. Clean lid.2. Lay the lid on the Disconnect Unit, slightly to one side.3. Screw grounding strap to the Disconnect Unit with

contact washer, washer, split lock washer and nut with a torque of 71 in-lbs. (8 Nm).

4. Push the lid forwards from the back beneath the straps.

Danger of crushing between the lid and the Disconnect Unit!• Note the weight of the lid of 37.5 lbs. (17 kg).• Install the lid of the Disconnect Unit with at least two persons.• Make sure that one person always hold the lid while the other person performs work at it.

Screws for Installing the LidScrews to affix the lid are found in a bag attached to the lid. Remove the bag and unpack the screws before affixing the lid.

Note the grounding strap on the lidA grounding strap is installed on the lid. The free end is affixed to the lid. Remove the adhesive strips before installing the lid. Connect the grounding strip to the Disconnect Unit as described below.

DISCONNECT UNITSMA



5. Align the lid flush with the sides and back of the Disconnect Unit. Holes in the front of the lid must be positioned to fit over the threads of the Disconnect Unit.

6. Install the lid on the Disconnect Unit using the screws provided.

7. Tighten screws with a torque of 18 in-lbs. (2 Nm).

8.3 Closing the Disconnect Unit

Figure 2: Position of the hooks for connecting the front plate.

Fully Installing the Disconnect UnitIf you are fully installing the Disconnect Unit in accordance with the Installation Guide, you will save time because the Disconnect Unit is already open. If the installation takes place later or at a different location, close the Disconnect Unit as described in this chapter.

Note before closing the Disconnect Unit• The handles on the front plate of the enclosure must be put into the "Off" position so that

the shafts can be engaged.• The two hooks for the front plate of the enclosure must be correctly positioned. The two

hooks are moveable and must be arranged 113⁄4 in. … 1 ft. 33⁄4 in. (300 mm … 400 mm) from the sides.

DISCONNECT UNITSMA

DISCONNECT UNIT SM



1. Screw the grounding strap in the bottom left corner of the Disconnect Unit to the front plate of the enclosure. Tighten screw with a torque of 71 in-lbs. (8 Nm).

2. Tip the front plate over with two persons so that the upper edge is pointing towards the Disconnect Unit. Hook the front plate of the enclosure onto the two hooks on the front of the Disconnect Unit.

3. Press the lower edge of the front plate of the enclosure onto the Disconnect Unit.

4. For each of the switch handles on the front of the front plate: Shake the handles gently a few times so that the switch shaft engages with the handle.

Danger of crushing caused by heavy front plate!• Note the weight of the front plate 110 lbs. (50 kg).• Move the front plate of the Disconnect Unit with at least two persons.• Ensure that one person is holding the front plate of the enclosure at all times when the other

person is working on it.

DISCONNECT UNITSMA



5. Fit the front plate of the enclosure to the Disconnect Unit with four screws and four sealing washers at its four corners. Tighten the screws so that they are hand-tight (the front plate of the enclosure can still be moved).

6. 11 accessible holes are left without screws on the front plate. The three holes behind the left handles are not reachable yet. Insert one screw with sealing washer in each of the 11 holes. Fasten the screws hand-tight.

7. Ensure that the front plate of the enclosure is aligned at the edges of the Disconnect Unit. Tighten all screws with a torque of 44 in-lbs. (5 Nm).

8. Ensure that all switches are functioning correctly. Switch all switches into the "On" position and then back into the "Off" position.The switches function properly if there is no clearance of the shafts and the switches make a clear switching noise. Readjust if necessary.

9. When all switches are functioning correctly: Switch all switches into the "On" position and insert three screws with sealing washers into the holes on the handles on the left-hand side. Tighten screws with a torque of 44 in-lbs. (5 Nm).

10. Switch all switches into the "Off" position.



11. For the Disconnect Unit for Sunny Central 500HE-US/CA/CP: Make sure that the grounding strap at the clamp of the AC switch is correctly connected to the flap and that it is not jammed between enclosure and flap. Close the flap after check.

SMA America, LLC Contact


9 ContactIf you have technical problems concerning our products, please contact our Serviceline. We require the following information in order to provide you with the necessary assistance:

• Device type• Serial number

SMA America, LLC 6020 West Oaks Blvd, Ste 300Rocklin, CA 95765Tel. +1 916 625 0870Tel. +1 877-MY SMA TECHTel. +1 877 697 6283 (Toll free, available for USA, Canada, and Puerto Rico)Fax +1 916 625 [email protected]

SMA Solar Technology Canada Inc.2425 Matheson Blvd. E8th FloorMississauga, ON L4W 5K5Canada

SMA America, LLC


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disconnect unit for sunny central 250u_500u_500he‑us and sunny central cp - unpacking...

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