SMA NR-PL-DCEMV5-01 User manual

SUNNY TRIPOWER
STP50-DC-EMV-DST-RM-xx-10 | 119812-00.01 | Version 1.0
Spare-part sets "EMC Filter Assembly" und
"DC Power Assembly" for SUNNY
TRIPOWER CORE1 (STP50-40) / CORE1-
US (STP50-US-40 / STP 33-US-41 / STP 50-
US-41 / STP 62-US-41) / CORE1-JP (STP50-
JP-40)
NR-PL-DCEMV5-01 / NR-PL-DCEMV5M-01 / NR-PL-DCEMV41-1 / NR-PL-DST5-01 /
NR-PL-DST1-41-1 / NR-PL-DST2-41-1

STP50-DC-EMV-DST-RM-xx-102
ENGLISH Replacement Manual................................................................3
DEUTSCH Austauschanleitung.................................................................27
ČEŠTINA Návod kvýměně ....................................................................52
ΕΛΛΗΝΙΚΑ Οδηγίες αντικατάστασης........................................................77
ESPAÑOL Instrucciones para la sustitución......................................... 103
FRANÇAIS Instructions de remplacement............................................. 128
ITALIANO Istruzioni per la sostituzione ............................................... 153
NEDERLANDS Vervangingshandleiding..................................................... 178
PORTUGUÊS Manual de substituição ....................................................... 203
ROMÂNĂ Instrucțiuni de schimb .......................................................... 228
TÜRKÇE Değiştirme kılavuzu ............................................................. 253
日本語 交換説明書........................................................................... 277
Contact...................................................................................302

Legal Provisions
SMA Solar Technology AG
Replacement Manual STP50-DC-EMV-DST-RM-xx-10 3
Legal Provisions
The information contained in these documents is the property of SMA Solar Technology AG. No
part of this document may be reproduced, stored in a retrieval system, or transmitted, in any form or
by any means, be it electronic, mechanical, photographic, magnetic or otherwise, without the prior
written permission of SMA Solar Technology AG. Internal reproduction used solely for the purpose
of product evaluation or other proper use is allowed and does not require prior approval.
SMA Solar Technology AG makes no representations or warranties, 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 representations or warranties are expressly disclaimed. Neither SMA Solar
Technology AG 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 product
improvements and field usage experience may cause SMA Solar Technology AG to make changes
to these specifications without advance notice or per contract provisions. SMA Solar Technology
AG 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.
Trademarks
All trademarks are recognized, even if not explicitly identified as such. Missing designations do not
mean that a product or brand is not a registered trademark.
SMA Solar Technology AG
Sonnenallee 1
34266 Niestetal
Germany
Tel. [phone]
Fax [phone]
www.SMA.de
Email: [email protected]
As of: 7/6/2020
Copyright © 2020 SMA Solar Technology AG. All rights reserved.
ENGLISH

Table of Contents SMA Solar Technology AG
Replacement ManualSTP50-DC-EMV-DST-RM-xx-104
Table of Contents
1 Information on this Document................................................. 5
1.1 Validity........................................................................................................................ 5
1.2 Target Group.............................................................................................................. 5
1.3 Content and Structure of this Document ................................................................... 5
1.4 Levels of Warning Messages.................................................................................... 5
1.5 Symbols in the Document .......................................................................................... 6
1.6 Typographical Elements in the Document ................................................................ 6
1.7 Designations in the Document................................................................................... 7
2 Safety ........................................................................................ 7
2.1 Intended Use .............................................................................................................. 7
2.2 IMPORTANT SAFETY INSTRUCTIONS.................................................................... 8
3 Overview of the Assemblies ................................................... 11
4 Scope of Delivery..................................................................... 11
4.1 Scope of delivery of DC/EMC assembly................................................................. 11
4.2 Scope of delivery of DST assembly .......................................................................... 12
5 Disconnecting the Inverter from Voltage Sources................. 12
6 Replacing the DC EMV Assembly ........................................... 14
6.1 Removing the DC EMV Assembly............................................................................. 14
6.2 Installing the DC EMV Assembly............................................................................... 17
7 Replacing the DST Assembly................................................... 18
7.1 Checking the New Assembly .................................................................................... 18
7.2 Removing the DST Assembly..................................................................................... 18
7.3 Installing the DST Assembly....................................................................................... 21
8 Commissioning the Inverter..................................................... 25
9 Returning and Disposing of the Defective Assembly ............ 26
ENGLISH

1 Information on this Document
SMA Solar Technology AG
Replacement Manual STP50-DC-EMV-DST-RM-xx-10 5
1 Information on this Document
1.1 Validity
This document is valid for:
• NR-PL-DCEMV5-01 (DC filter assembly)
• NR-PL-DCEMV5M-01 (EMC filter assembly)
• NR-PL-DCEMV41-01 (EMC filter assembly)
• NR-PL-DST5-01 (DC power assembly)
• NR-PL-DST1-41-1 (DC power assembly)
• NR-PL-DST2-41-1 (DC power assembly)
1.2 Target Group
The tasks described in this document must only be performed by qualified persons. Qualified
persons must have the following skills:
• Within the SMA factory warranty, participation in an SMA training course is mandatory for
carrying out the activities described in this document. The type of training and the media used
may vary from country to country. The type and method of training can therefore vary from
country to country, but must have been completed before the service is provided.
• Outside the SMA factory warranty, SMA Solar Technology AG recommends participation in
an SMA training course to perform the activities described in this document. This ensures the
quality requirements for proper replacement of assemblies. The type of training and the media
used may vary from country to country.
• Knowledge of how to safely disconnect SMA inverters
• Knowledge of how an inverter works and is operated
• Training in how to deal with the dangers and risks associated with installing, repairing and
using electrical devices and installations
• Training in the installation and commissioning of electrical devices and installations
• Knowledge of all applicable laws, standards and directives
• Knowledge of and compliance with this document and all safety information
1.3 Content and Structure of this Document
This document describes how to replace components.
Illustrations in this document are reduced to the essential information and may deviate from the real
product.
1.4 Levels of Warning Messages
The following levels of warning messages may occur when handling the product.
DANGER
Indicates a hazardous situation which, if not avoided, will result in death or serious injury.
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1 Information on this Document SMA Solar Technology AG
Replacement ManualSTP50-DC-EMV-DST-RM-xx-106
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 a situation which, if not avoided, can result in property damage.
1.5 Symbols in the Document
Symbol Explanation
Information that is important for a specific topic or goal, but is not safety-rele-
vant
☐
Indicates a requirement for meeting a specific goal
☑
Desired result
✖
A problem that might occur
Example
Sections describing activities to be performed by qualified persons only
1.6 Typographical Elements in the Document
Typography Use Example
bold • Messages
• Terminals
• Elements on a user interface
• Elements to be selected
• Elements to be entered
• Connect the insulated
conductors to the terminals
X703:1 to X703:6.
• Enter 10 in the field
Minutes.
>• Connects several elements to be
selected
• Select Settings > Date.
[Button]
[Key]
• Button or key to be selected or
pressed
• Select [Enter].
# • Placeholder for variable
components (e.g., parameter
names)
• Parameter WCtlHz.Hz#
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2 Safety
SMA Solar Technology AG
Replacement Manual STP50-DC-EMV-DST-RM-xx-10 7
1.7 Designations in the Document
Complete designation Designation in this document
SunnyTripower Inverter, product
DC power assembly (DST) DST assembly, DST, assembly
EMC filter assembly (DC-EMV) DC-EMV assembly, DC-EMV, assembly
2 Safety
2.1 Intended Use
The product must only be installed in the following SMA inverters:
Spare parts set Inverters
NR-PL-DCEMV5M-01 STP 50-40
STP 50-JP-40
NR-PL-DCEMV5M-01 STP 50-US-40
NR-PL-DCEMV41-1 STP 33-US-41
STP 50-US-41
STP 62-US-41
NR-PL-DST5-01 STP 50-40
STP 50-JP-40
STP50-US-40
NR-PL-DST1-41-1
NR-PL-DST2-41-1
STP 33-US-41
STP 50-US-41
STP 62-US-41
Use SMA products only in accordance with the information provided in the enclosed
documentation and with the locally applicable laws, regulations, standards and directives. Any
other application may cause personal injury or property damage.
Alterations to the SMA products, e.g., changes or modifications, are only permitted with the express
written permission of SMA Solar Technology AG. Unauthorized alterations will void guarantee and
warranty claims and in most cases terminate the operating license. SMA Solar Technology AG
shall not be held liable for any damage caused by such changes.
Any use of the product other than that described in the Intended Use section does not qualify as the
intended use.
The enclosed documentation is an integral part of this product. Keep the documentation in a
convenient, dry place for future reference and observe all instructions contained therein.
This document does not replace and is not intended to replace any local, state, provincial, federal
or national laws, regulations or codes applicable to the installation, electrical safety and use of the
product. SMA Solar Technology AG assumes no responsibility for the compliance or non-
compliance with such laws or codes in connection with the installation of the product.
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2 Safety SMA Solar Technology AG
Replacement ManualSTP50-DC-EMV-DST-RM-xx-108
If the replacement and all activities stated in this document are carried out by persons who are not
qualified within the meaning of this documentation, this will void the guarantee and warranty claims
and in most cases terminate the operating permit. SMA Solar Technology AG shall not be held
liable for any damage caused directly or indirectly due to such changes by unauthorized persons.
2.2 IMPORTANT SAFETY INSTRUCTIONS
SAVE THESE INSTRUCTIONS
This section contains safety information that must be observed at all times when working.
The product has been designed and tested in accordance with international safety requirements. As
with all electrical or electronical devices, there are residual risks despite careful construction. To
prevent personal injury and property damage and to ensure long-term operation of the product,
read this section carefully and observe all safety information at all times.
DANGER
Danger to life due to electric shock when live components or cables of the
inverter are touched
High voltages are present in the conductive components or cables of the inverter. Touching live
parts and cables of the inverter results in death or lethal injuries due to electric shock.
• Disconnect the inverter from voltage sources and make sure it cannot be reconnected
before working on the device.
• After disconnection, wait 5 minutes until the capacitors have discharged.
• Wear suitable personal protective equipment for all work on the product.
• Do not touch non-insulated parts or cables.
DANGER
Danger to life due to electric shock when live components or DC cables are
touched
When exposed to light, the PV modules generate high DC voltage which is present in the DC
cables. Touching live DC cables results in death or lethal injuries due to electric shock.
• Do not touch non-insulated parts or cables.
• Disconnect the inverter from voltage sources and make sure it cannot be reconnected
before working on the device.
• Do not disconnect the DC connectors under load.
• Wear suitable personal protective equipment for all work on the product.
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2 Safety
SMA Solar Technology AG
Replacement Manual STP50-DC-EMV-DST-RM-xx-10 9
DANGER
Danger to life due to electric shock when touching live system components in
case of a ground fault
If a ground fault occurs, parts of the system may still be live. Touching live parts and cables
results in death or lethal injuries due to electric shock.
• Disconnect the inverter from voltage sources and make sure it cannot be reconnected
before working on the device.
• Touch the cables of the PV array on the insulation only.
• Do not touch any parts of the substructure or frame of the PV array.
• Do not connect PV strings with ground faults to the inverter.
WARNING
Danger to life due to fire or explosion
In rare cases, an explosive gas mixture can be generated inside the inverter under fault
conditions. In this state, switching operations can cause a fire inside the inverter or explosion.
Death or lethal injuries due to hot or flying debris can result.
• In the event of a fault, do not perform any direct actions on the inverter.
• Ensure that unauthorized persons have no access to the inverter.
• Do not operate the DC load-break switch on the inverter in the event of ground fault
• Disconnect the PV array from the inverter via an external disconnection device. If there is no
disconnecting device present, wait until no more DC power is applied to the inverter.
• Disconnect the AC circuit breaker, or keep it disconnected in case it has already tripped,
and secure it against reconnection.
• Only perform work on the inverter (e.g., troubleshooting, repair work) when wearing
personal protective equipment for handling of hazardous substances (e.g., safety gloves,
eye and face protection, respiratory protection).
WARNING
Risk of injury due to toxic substances, gases and dusts.
In rare cases, damages to electronic components can result in the formation of toxic substances,
gases or dusts inside the inverter. Touching toxic substances and inhaling toxic gases and dusts
can cause skin irritation, burns or poisoning, trouble breathing and nausea.
• Only perform work on the inverter (e.g., troubleshooting, repair work) when wearing
personal protective equipment for handling of hazardous substances (e.g., safety gloves,
eye and face protection, respiratory protection).
• Ensure that unauthorized persons have no access to the inverter.
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2 Safety SMA Solar Technology AG
Replacement ManualSTP50-DC-EMV-DST-RM-xx-1010
WARNING
Danger to life due to electric shock from destruction of the measuring device
due to overvoltage
Overvoltage can damage a measuring device and result in voltage being present in the
enclosure of the measuring device. Touching the live enclosure of the measuring device results in
death or lethal injuries due to electric shock.
• Only use measuring devices with a DC input voltage range of 1000V or higher.
CAUTION
Risk of burns due to hot enclosure parts
The enclosure and the enclosure lid may get hot during operation. The DC load-break switch can
not become hot.
• Do not touch hot surfaces.
• Wait until the inverter has cooled down before touching the enclosure or enclosure lid.
NOTICE
Damage to the enclosure seal in subfreezing conditions
If you open the inverter when temperatures are below freezing, the enclosure seals can be
damaged. This can lead to moisture entering the inverter.
• Only open the inverter if the ambient temperature is not below -5°C (23°F).
• If a layer of ice has formed on the enclosure seal when temperatures are below freezing,
remove it prior to opening the inverter (e.g. by melting the ice with warm air).
NOTICE
Damage to the inverter due to sand, dust and moisture
Sand, dust and moisture penetration can damage the inverter, thus impairing its functionality.
• Only open the inverter if the humidity is within the thresholds and the environment is free of
sand and dust.
• Do not open the inverter during a dust storm or precipitation.
• Close the inverter in case of interruption of work or after finishing work.
NOTICE
Damage to the inverter due to electrostatic discharge
Touching electronic components can cause damage to or destroy the inverter through
electrostatic discharge.
• Ground yourself before touching any component.
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3 Overview of the Assemblies
SMA Solar Technology AG
Replacement Manual STP50-DC-EMV-DST-RM-xx-10 11
Grounding conductor test prior to recommissioning
Prior to recommissioning SMA inverters after the installation of SMA components or power
assemblies which cannot be replaced intuitively, ensure that the grounding conductor in the
inverter is correctly connected. The function of the grounding conductor must be ensured and
all locally applicable laws, standards and directives must be observed.
Observe superordinate standards
The repair work on devices and the consideration and application of other standards which
correspond to a superordinate standard is the responsibility of the qualified person performing
the work. Unauthorized alterations will void guarantee and warranty claims and in most cases
terminate the operating license. SMA Solar Technology AG shall not be held liable for any
damage caused by such changes.
3 Overview of the Assemblies
DC-
Connection Unit
AC-
Connection Unit
DC-Power Unit
AC-Power Unit
COM
DCEMV
BFS
DST
AST
ACRLY
LED
A
Figure 1 : Position of the assemblies in the inverter
Position Designation
A AC load-break switch (only present with STP 50-US-40 / STP 33-US-41 / STP
50- US-41 / STP 62-US-41)
4 Scope of Delivery
4.1 Scope of delivery of DC/EMC assembly
Check the scope of delivery for completeness and any externally visible damage. Contact your
distributor if the scope of delivery is incomplete or damaged.
Designation Quantity
DC EMV assembly 1
Bolt M4 x 15 4
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5 Disconnecting the Inverter from Voltage Sources SMA Solar Technology AG
Replacement ManualSTP50-DC-EMV-DST-RM-xx-1012
Designation Quantity
Bolt M6 x 12 4
Replacement Manual 1
4.2 Scope of delivery of DST assembly
Check the scope of delivery for completeness and any externally visible damage. Contact your
distributor if the scope of delivery is incomplete or damaged.
Designation Quantity
DST assembly 1
Bolt M4 x 15 22
Bolt M6 x 12 8
Cleaning cloth 4
Replacement Manual 1
5 Disconnecting the Inverter from Voltage Sources
Prior to performing any work on the inverter, always disconnect it from all voltage sources as
described in this section. Always adhere to the prescribed sequence.
WARNING
Danger to life due to electric shock from destruction of the measuring device
due to overvoltage
Overvoltage can damage a measuring device and result in voltage being present in the
enclosure of the measuring device. Touching the live enclosure of the measuring device results in
death or lethal injuries due to electric shock.
• Only use measuring devices with a DC input voltage range of 1000V or higher.
Procedure:
1. Disconnect the AC circuit breaker and secure it against reconnection.
2. For STP 50-US-40 / STP 33-US-41 / STP 50-US-41 / STP 62-US-41: Set the AC load-break
switch of the inverter to position O.
3. Set the DC load-break switch of the inverter to position O.
4. If the multifunction relay is used, switch off any supply voltage to the load.
5. Wait until the LEDs have gone out.
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5 Disconnecting the Inverter from Voltage Sources
SMA Solar Technology AG
Replacement Manual STP50-DC-EMV-DST-RM-xx-10 13
6. Use a current clamp to ensure that no current is
present in the DC cables.
A
B
C
<0.5A<0.5A
7. Note the position of the DC connector.
8. DANGER
Danger to life due to electric shock when touching exposed DC
conductors or DC plug contacts if the DC connectors are damaged or
loose
The DC connectors can break or become damaged, become free of the DC cables, or no
longer be connected correctly if the DC connectors are released and disconnected
incorrectly. This can result in the DC conductors or DC plug contacts being exposed.
Touching live DC conductors or DC plug connectors will result in death or serious injury due
to electric shock.
• Wear insulated gloves and use insulated tools when working on the DC connectors.
• Ensure that the DC connectors are in perfect condition and that none of the DC
conductors or DC plug contacts are exposed.
• Carefully release and remove the DC connectors as described in the following.
9. For STP 50-40 / STP 50-JP-40 (use of Sunclix DC
connectors): Release and remove the DC
connectors. To do so, insert a flat-blade screwdriver
or an angled screwdriver (blade width: 3.5mm) into
one of the side slots and pull the DC connectors out.
When doing so, do not lever the DC connectors out,
but insert the tool into one of the side slots only to
release the locking mechanism, and do not pull on
the cable.
1
2
10. For STP 50-US-40 / STP 33-US-41 / STP 50-US-41 / STP 62-US-41 (use of Amphenol DC
connectors): Unlock the DC connectors using the corresponding unlocking tool and remove
(refer to the manufacturer manual for further information).
11. Ensure that the DC connectors on the product and those that are equipped with DC
conductors are in perfect condition and that none of the DC conductors or DC plug contacts
are exposed.
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6 Replacing the DC EMV Assembly SMA Solar Technology AG
Replacement ManualSTP50-DC-EMV-DST-RM-xx-1014
12. Ensure that no voltage is present at the DC inputs on
the inverter using a suitable measuring device.
A
B
C
<30V
13. Unscrew (TX25) all ten screws of the enclosure lid of
the AC-ConnectionUnit and remove the enclosure
lid carefully towards the front.
10x
14. Set the screws and the enclosure lid aside and store safely.
15. Ensure there is no voltage on the AC terminal block between L1 and N, L2 and N, and L3 and
N using a suitable measuring device. To do so, insert the test probe (maximum diameter:
2.5mm (0.078in)) into the measuring points of the respective terminal blocks.
16. Ensure that there is no voltage on the AC terminal block between L1 and grounding
conductor, L2 and grounding conductor, and L3 and grounding conductor using a suitable
measuring device. To do so, insert the test probe (maximum diameter: 2.5mm (0.078in)) into
the measuring points of the respective terminal blocks.
6 Replacing the DC EMV Assembly
6.1 Removing the DC EMV Assembly
NOTICE
Damage in the inverter due to incorrect removal of assemblies
There are several assemblies mounted one behind the next in the inverter. Bulky components are
mounted on the rear of some assemblies. When removing an assembly, the assembly behind this
can be damaged due to incorrect removal.
• Remove assemblies that have been disconnected to the front to avoid contact between the
assemblies.
Procedure:
1. Disconnect the inverter from all voltage sources (see Section5, page12).
2. Wait 5 minutes. This will ensure that the capacitors are discharged.
3. Remove the enclosure lid of the DC-PowerUnit (TX25) by pulling it towards the front.
4. Discharge the DC EMC assembly at the contact points using a voltage detector without
intrinsic voltage source. Ensure that the residual voltage is less than 5V.
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6 Replacing the DC EMV Assembly
SMA Solar Technology AG
Replacement Manual STP50-DC-EMV-DST-RM-xx-10 15
• Connectors (red, light blue, white, green, black
and lilac) against grounding conductor
(enclosure)
• Bolted connections (black, blue) against
grounding conductor (enclosure)
• Connector (red, light blue, white) against black
bolted connection
• Connector (green, black, purple) against blue
bolted connection
5. Ground yourself prior to replacing the assembly to prevent ESD damage.
6. Disconnect cables (red, light blue, white, green,
black and purple) from the top and bottom of the
assembly. Use a suitable screwdriver to remove the
cables from the terminals and ensure that the ferrites
are not damaged.
7. Unplug the ribbon cable connector. Unlock the plug
first.
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6 Replacing the DC EMV Assembly SMA Solar Technology AG
Replacement ManualSTP50-DC-EMV-DST-RM-xx-1016
8. Remove the 4 screwed DC power connections
(TX20 or TX30). If the bolting block and the terminal
lug stick together, the contact surfaces must be
ground prior to the next connection being made.
Ensure that no grinding filings remain in the device.
9. Clean the contact surfaces on the bolting block and terminal lugs with a suitable cleaning
agent to remove bolt coating deposits.
10. Remove the cables from the working area.
11. Remove the 4 DC EMC assembly mounting plate
connecting screws (TX20). Once the screws have
been removed, the assembly mounting plate
remains held in place by the spacers.
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6 Replacing the DC EMV Assembly
SMA Solar Technology AG
Replacement Manual STP50-DC-EMV-DST-RM-xx-10 17
12. Remove the DC EMC assembly from the inverter. When doing so, only hold the assembly by
the handling areas (see Section6.2, page17) and ensure that the fan located on the rear
side of the carrier plate does not damage the DST assembly in the inverter.
13. If necessary, replace the DST assembly now (see Section7, page18). If only the DC-EMC
assembly is to be replaced, proceed with the installation of the DC-EMC assembly (see
Section6.2, page17).
6.2 Installing the DC EMV Assembly
A
A
A
A
Figure 2 : Handling area of DC-EMV assembly
Position Designation
A Touch only the assembly on the marked areas or on the sheet metal located
underneath the assembly.
Additionally the protected edges of the mounting plate behind the assembly can be used for the
handling.
The remaining areas may not be touched. The assembly can be damaged through touching.
Procedure:
1. Align the assembly and insert it into the inverter. Touch the assembly only at the handling
areas. Ensure that the spacers match the holes in the mounting plate and that the cable is not
trapped beneath the mounting plate.
2. Tighten the 4 assembly connecting screws (TX20, torque: 3.5Nm (31.0in-lb)).
3. Insert the cables (red, light blue, white, green, black and purple) into the terminals at the top
and bottom of the assembly and ensure that all cables are firmly seated.
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7 Replacing the DST Assembly SMA Solar Technology AG
Replacement ManualSTP50-DC-EMV-DST-RM-xx-1018
4. Plug the ribbon cable connector into the assembly and ensure that the lock has snapped into
place.
5. Tighten the screwed DC power connections using the bolts from the scope of delivery (TX25,
torque: 6.0Nm (53.1in-lb)). Ensure the correct position when doing so (BU = blue, BK =
black).
6. Ensure that all connections for the replaced assembly have been made correctly.
7. Position the enclosure lid on the DC-Connection Unit and first tighten the upper-left and lower-
right screws, and then the remaining screws crosswise (TX25, torque: 6Nm (53in-lb)).
8. Commission the inverter (see Section8, page25).
7 Replacing the DST Assembly
7.1 Checking the New Assembly
To ensure that the replacement of the assembly can be performed, the status of the new assembly is
to be checked prior to removal of the defective assembly.
Procedure:
1. Carefully remove the assembly upwards out of the packaging. When doing so, ensure that the
thermal grease is not damaged or contaminated.
2. Check the pattern of thermal grease on the rear of the assembly for damage and impurities.
3. If the pattern of thermal grease on the rear side of
the assembly shows evidence of damage, the
assembly must be replaced. If small impurities (see
image) are present, these can be carefully removed
using a pointed tool. The pattern must not be
destroyed when doing so.
4. Lay the assembly in the packaging until use.
7.2 Removing the DST Assembly
Requirements:
☐ The pattern of thermal grease must be undamaged and free from impurities (see Section7.1,
page18).
Procedure:
1. Disconnect the inverter from all voltage sources (see Section5, page12).
2. Remove the DC EMV assembly (see Section6.1, page14).
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7 Replacing the DST Assembly
SMA Solar Technology AG
Replacement Manual STP50-DC-EMV-DST-RM-xx-10 19
3. Disconnect cables (1 red, 2 light blue, 1 white, 1
green, 1 black and 1 purple) from the assembly.
Use a suitable screwdriver to remove the cables
from the terminals.
4. Unplug the connections. When doing so, unlock the
ribbon cable plug first.
5. Remove the screws on the power connections from
the DST assembly (TX20 or TX30). If the bolting
block and the terminal lug stick together, the contact
surfaces must be ground prior to the next connection
being made. Ensure that no grinding filings remain
in the device.
6. Clean the contact surfaces on the bolting block and terminal lugs with a suitable cleaning
agent to remove bolt coating deposits.
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7 Replacing the DST Assembly SMA Solar Technology AG
Replacement ManualSTP50-DC-EMV-DST-RM-xx-1020
7. Remove the connecting screws of the power
modules (TX20).
8. Remove the connecting screws of the DST assembly
(TX20). The assembly will also remain held in place
by the spacers once the screws have been removed.
9. Remove the DST assembly cables from the working area.
10. To remove the assembly from the inverter, first carefully swing the left-hand side of the
assembly out of the inverter and lead the assembly past the connections out of the inverter.
ENGLISH