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SMA Sunny Island 4248U Installation & Operating Instructions Manual

Battery inverter/charger for stand-alone applications
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SI4248U Installation Guide
Sunny Island 4248U
Battery Inverter/Charger
for Stand-Alone Applications
Installation & Operating Instructions
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Summary of Contents for SMA Sunny Island 4248U

  • Page 1 SI4248U Installation Guide Sunny Island 4248U Battery Inverter/Charger for Stand-Alone Applications Installation & Operating Instructions...
  • Page 2 SI4248U Installation Guide...
  • Page 3 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 reserves the right to make changes without notice and shall not be responsible for any damages, including indirect, incidental or consequential...
  • Page 4 Sunny Island 4248U. To reduce the risk of personal injury and to ensure the safe installation and operation of the Sunny Island 4248U, you must carefully read and follow all instructions and warnings in this Installation Guide.
  • Page 5 SI4248U Installation Guide Warranty All Sunny Island 4248U inverters sold in the USA have a five-year warranty, as indicated on the warranty card included in the shipping container. For warranty coverage, or if you have questions about the Sunny Island 4248U warranty, contact SMA America at the address, telephone number or Web site listed on page iii (to send E-mail, see the Contact section of the SMA America Web site: www.sma-america.com).
  • Page 6 SI4248U Installation Guide...

  • Page 7: Table Of Contents

    Sunny Boy Set Up ......42 Sunny Island 4248U Menu Tree ..... . 44 Installer Level Menu Guide .
  • Page 8 SI4248U Installation Maintenance ........81 Battery Management ......83 Charging Operations used by the Sunny Island .

  • Page 9: Installation Manual

    Sunny Island 4248U. As a result, the Sunny Island 4248U represents state-of-the-art technology, high reliability and overall ease of use, all the things you’ve come to expect from SMA, the industry leader in inverter manufacturing. Some of the features included are: •...

  • Page 10: Specifications

    SI4248U Manual Code Compliance The Sunny Island 4248U has been tested and listed by ETL to meet the requirements of UL 1741 Static Inverters and Charge Controllers for use in Photovoltaic Power Systems. The Sunny Island 4248U also meets all RFI/EMI requirements of FCC Part 15, part b.
  • Page 11 1000 W 2000 W 3000 W 4000 W Output Power [Pac] Figure 1-2 Sunny Island 4248U Efficiency Curve Output Power 25 °C 45 °C 50 °C 100ms 1 min 30 min continuous Figure 1-3 Sunny Island 4248U Output Power Curves...

  • Page 12: Safety

    Safety SI4248U Manual Safety Safety Features The Sunny Island 4248U is equipped with several safety related components. Some of the safety features included are: • Built in DC disconnect • AC input current limiting to protect generator • Automatic fan control •...
  • Page 13 Installation Manual RFI/EMI The Sunny Island 4248U has been tested and complies with the requirements of FCC part 15 rules for Class B digital devices. FCC part 15 was written to provide reasonable protection against harmful interference caused by electronic devices in a residential installation.

  • Page 14: Preparation

    • Keep all receipts together for future reference The lid of the Sunny Island 4248U is not mounted when you receive the device. The lid is packed in a bag to prevent damages during shipping. You have to unpack the lid and fasten it to the enclosure of the Sunny Island 4248U after the installation.
  • Page 15 (step 1) before lifting the cover off (step 2). Failure to do so can result in the DC breaker being accidentally switched on. The lid of the Sunny Island 4248U is not mounted when you receive it. You have to remove the plastic bag in which the Sunny Island 4248U is packed and after that you can mount the lid.
  • Page 16 SI4248U Manual Mounting Location The Sunny Island 4248U must be mounted indoors in an area where it is easily accessible and out of the elements. It is important that the Sunny Island 4248U not be mounted directly over the battery bank for corrosion and safety reasons. Mount the inverter off to one side of the battery bank or perhaps on the other side of the same wall if convenient.
  • Page 17 1 1/2 inches. For additional support, the Sunny Island 4248U may be mounted to 2 x 4 braces, Uni- Strut or a sheet of plywood that is secured to the building support structure.
  • Page 18 Preparation SI4248U Manual User Interface Overview The following illustration shows the names and locations of the components that make up the Sunny Island 4248U’s user interface.

  • Page 19: Installation

    Special Tools It is helpful to have a laptop on hand with the Sunny Data software installed, a communication cable and an RS232 Piggy-Back module for communication with the Sunny Island 4248U (but is not required to complete installation). Hardware The type of hardware required to mount the inverter will vary depending upon the mounting method used.

  • Page 20: Mounting

    Single Stud Mounting The Sunny Island 4248U can be mounted to a single wall stud if necessary. It must be mounted with the holes centered on the stud and the lag bolts must penetrate the stud to a depth of at least 1 1/2”.
  • Page 21 SI4248U Manual Installation Manual Figure 1-9 Mounting Bracket to Single Stud...
  • Page 22 Installation SI4248U Manual Using Wall Braces For additional security, the Sunny Island 4248U may be mounted by attaching a pair of wall braces horizontally. It is recommended that the wall braces span three studs for secure mounting. • Locate the wall studs and mark their location on the wall •...
  • Page 23 SI4248U Manual Installation Manual Figure 1-10 Mounting With 2x4 Braces...
  • Page 24 Installation SI4248U Manual Mounting with Plywood NOTE: To mount the inverter with plywood, a 3/4” plywood should be used. (Do not use laminated pressboard or MDF, etc.) • Locate the wall studs and mark their location on the wall • Locate desired height of inverter remembering to keep the user interface near eye level •...
  • Page 25 SI4248U Manual Installation Manual Figure 1-11 Mounting With Sheet of Plywood...

  • Page 26: System Configuration

    DC power, an inverter is needed to change the DC voltage to an AC voltage that can be used by the AC loads. This is exactly what the Sunny Island 4248U was designed to do. The Sunny Island 4248U can also function as a battery charger for charging the battery bank.
  • Page 27 When used as a back-up system, the Sunny Island 4248U is designed to begin providing AC power automatically whenever the primary source of AC power shuts down.

  • Page 28: Conductor Types And Sizes

    When the inverter is in Silent Mode, it is indicated on the display by “Silent“. The Sunny Island 4248U also has the ability to connect external sources of power, such as a gas powered generator to assist in powering the loads and charging the battery bank during extended outages.
  • Page 29 (see NEC 250.122(B)). If the full 56 A pass-through rating of the Sunny Island 4248U is to be used, then 6 AWG conductors and 70 A circuit breakers must be used in the AC input and output circuits (The commonly used 60 A inverter disconnect switch cannot be used in this application).
  • Page 30 NOTE: The recommended length for the DC battery cables is <10 ft and should not exceed 20 feet. The Sunny Island 4248U comes equipped with a 175 A DC circuit breaker which allows for improved transient surge capability. The battery conductors must be sized in accordance with this circuit breaker and should be sized at 2/0 AWG (which has a rating of 175 A at 30 °C).
  • Page 31 AC grounding electrode conductor (GEC). From this bonding point, the AC GEC is run to the AC grounding electrode or grounding system (see NEC 250.). The DC part of the system must also be bonded to ground. The Sunny Island 4248U is designed to work with a negatively grounded DC electrical system.
  • Page 32 SI4248U Manual Automatic Load Shedding and Generator Start The Sunny Island 4248U is capable of shutting off specified loads automatically if a low battery condition is present. The relay that controls those loads is connected to the NC contact terminals. The Sunny Island 4248U can also start back-up generators automatically. The Sunny Island 4248U can operate two-wire gen-start circuits with this relay alone.
  • Page 33 GenMan option (GenMan is an optional unit available from SMA America). When the generator has been started, the GenMan will confirm operation by sending a signal to these terminals. In this way, the Sunny Island 4248U can determine wether the generator is functioning properly or not.
  • Page 34 The Sunny Island 4248U is equipped with fans to help maintain efficiency during high loads or high ambient temperatures. Power for the fans is provided here. Also, the external battery temperature sensor is connected here to monitor the battery temperature and make adjustments to the charge level accordingly.
  • Page 35 SI4248U Manual Installation Manual Controller Area Network (CAN) The CAN connections are used when two Sunny Island 4248U’s are used in split-phase configuration. Please see the split-phase section of this manual for further details. Terminal Function SHIELD Reserved for split-phase...

  • Page 36: Wiring Instructions

    Installation SI4248U Manual Wiring Instructions Conduit Begin by installing conduits in the appropriate holes in the bottom of the inverter. NOTE: All conduit used should be metallic (EMT). NOTE: All DC conduit from the inverter to the battery should be metallic to meet US FCC and European EN electromagnetic radiation requirements.
  • Page 37 SI4248U Manual Installation Manual Torque Specifications Torque all terminations to the following values. Terminal Torque Value DC Positive 35 - 50 ft. lbs. DC Negative Equipment Ground AC Power In/Out 18 - 35 in. lbs. Auxiliary/Communication 4 in. lbs. Table 1-8: Torque Specifications 1 1/2”...
  • Page 38 WARNING: The Sunny Island 4248U does not make any connection between the DC positive or negative circuits and ground. The required connection must be made by the installer. The Sunny Island 4248U is designed to operate in negative- grounded systems.
  • Page 39 NOTE: The battery temperature sensor must be connected for the inverter to function properly. • Use only the BTS that came with the Sunny Island 4248U • Do not lengthen the BTS cable • Do not drill holes in any part of the batteries to mount the sensor unless instructed to do so by the battery manufacturer •...
  • Page 40 Installation SI4248U Manual NOTE: In split-phase mode with two Sunny Island 4248U’s connected together, the slave unit must have the battery temperature sensor connected to set the inverter to “slave” mode. Once the inverter is set to “slave” mode, it does not require the battery temperature sensor and can be removed.
  • Page 41 SI4248U Manual Installation Manual AC Wiring Connect the AC wiring beginning with the equipmend ground conductor (green or bare) to the PE terminal, followed by the neutral conductor (white) to the N terminal and finally the line conductor (black) to the L terminal. If your system is equipped with a generator, connect the incoming AC wires from the generator in the same order as above.
  • Page 42 No damage will result if the above warning is heeded and the inverter has not been powered on for at least five minutes. NOTE: The DC cables that supply power to the Sunny Island 4248U should be connected directly between the inverter and the battery bank only (via additional disconnect and over-current protection if required).

  • Page 43: Split-Phase

    Split-Phase Split-phase Systems The Sunny Island 4248U has the ability to work together in split-phase mode with another Sunny Island 4248U to provide 240 V AC capabilities. When used in split-phase mode, one inverter is set up to be the “Master” unit, and the other the “Slave”...
  • Page 44 CAN_H Figure 1-20 Sync Connection for Split-Phase AC coupled energy sources can be connected either to the Master Sunny Island 4248U (L1-N, 120 V) or to both outer conductors (L1-L2, 240 V). They MUST NOT be connected to the slave Sunny Island 4248U only (L2-N).

  • Page 45: Commissioning

    Battery Type: _____________ Valve Regulated Lead Acid (VRLA) or Flooded Lead Acid (FLA) **Battery Capacity: ________ Amp Hours (100 to 6000) **The Sunny Island 4248U assumes a C20 (twenty hour capacity) value for capacity NOTE: Some batteries list the amp-hour capacity in the 10 hr. rate on the label.
  • Page 46 SI4248U Manual User Interface Overview To commission the Sunny Island 4248U, you will need to interact with the user interface. The basic configuration of the user interface is shown in the figure below. The user interface consists of a DC disconnect, a 2-line digital display, two status indicators, up and down arrows, an Escape and an Enter key.
  • Page 47 SI4248U Manual Installation Manual LED Indicators There are two LED indicators on the front of the Sunny Island 4248U, one red and one green. The following table describes their functionality. Operating Condition Red LED Green LED INIT (Initialization) Stop Operating...
  • Page 48 Then use the up and down arrows to select the correct value. (Holding the arrows will cause the value to change Press: Enter/Arrow Keys/Enter more quickly.) Then press Enter to store the new value. The Sunny Island 4248U shows the maximum charging current. AmpacBatMax xx A Press: Enter The inverter is now ready to run.
  • Page 49 Reset Sunny Island 4248U to factory settings In order to reset the Sunny Island 4248U to its delivery status, switch the inverter off with the DC disconnect. Press and hold [ ESC ] and [Arrow Up] button. Switch the DC disconnect on, still pressing the buttons.

  • Page 50: Sunny Boy Set Up

    500 Amp hours. Off-Grid Systems If you’re using Sunny Boy inverters in the system you will need to set the Sunny Island 4248U to interface with the Sunny Boys. You will also have to set a parameter in the Sunny Boys to work with the Sunny Island 4248U.
  • Page 51 AC voltage is approximately 120 V AC. Well Done! The Sunny Island 4248U is now ready to operate normally (If perchance the inverter is not running at this point, refer to the Troubleshooting guide and correct the error...

  • Page 52: Sunny Island 4248U Menu Tree

    Sunny Island 4248U Menu Tree SI4248U Manual Sunny Island 4248U Menu Tree The installer menus are arranged in four simple groups: Meters, Settings, Diagnose and Operation. Using the information from the previous section, each of the parameters can be navigated to and changed if needed. The following diagram shows a simple map of the parameters that are viewable at the installer level.

  • Page 53: Installer Level Menu Guide

    SI4248U Manual Installation Manual Installer Level Menu Guide The following tables contain information on each of the menu items which are intended to be modified only by the installer (A guide to the menu items available to the user is found in the user’s section of this manual).
  • Page 54 Installer Level Menu Guide SI4248U Manual Battery Meters (12) Range/ Name Default Description Unit BatVoltage 0 - 80 The BatVoltage menu displays the battery voltage. BatCurrent -200 - The BatCurrent menu displays the DC current. +200 BatTemp -40 - The BatTemp menu displays the battery tempera- +200 ture.

  • Page 55: Settings

    SI4248U Manual Installation Manual Generator Meters (13) Range/ Name Default Description Unit VacGenerator 0 - 260 The VacGenerator menu displays the AC voltage at the inverter generator input. AmpacGenerat 0 - 60 The AmpacGenerator menu displays the AC current at the inverter generator input. FacGenerator 0 - 70 The FacGenerator menu displays the AC frequency...
  • Page 56 Installer Level Menu Guide SI4248U Manual Range/ Name Default Description Unit AmpHoursBat 100 - The BatCapacity parameter sets the total amp-hour 6000 capacity of the battery bank. This parameter needs to be set when the inverter is first commissioned. Once the system is configured, this parameter can only be changed after selecting "Reset"...
  • Page 57 The AmpGenMax Parameter should be set to about 85 % of the maximum AC current of your genera- tor. In Charge Mode the Sunny Island 4248U will then limit the total current (loads in the system + Sunny Island) to this value in order to prevent the generator from stalling.
  • Page 58 If the generator voltage is lower than this limit when running unloaded the Sunny Island 4248U will not connect, or, if the generator voltage goes below this limit while connected the Sunny Island 4248U will...
  • Page 59 ... 60.48 Hz), reverse power limit is 6.72 kW. DelayVGenLow 500 - 3000 The DelayVGenLow parameter selects the amount 6000 of time the Sunny Island 4248U will wait before dis- connecting when the generator voltage or fre- quency drops below the VacGenMin or FacGenMin limits. Transition Ramp/...

  • Page 60: Diagnose

    Installer Level Menu Guide SI4248U Manual Diagnose System Information (31) Range/ Name Default Description Unit DeviceConfig SI4248 The DeviceConfig parameter displays the name of the device. FWVers The FWVers menu displays the version number of the firmware installed in the inverter. SerNum The SerNum menu displays the serial number of the inverter.

  • Page 61: Operation

    AutoStart is OFF, the inverter will always have to be started manually. BaudRate 1200, 1200 The BaudRate parameter selects the baud rate that 2400, the Sunny Island 4248U will use to communicate 4800, with external devices. 9600, 19200 ParameterSet None,...
  • Page 62 Select No when there are no Sunny Boy inverters in the system. Select Yes when there are Sunny Boy inverters used in the same system with the Sunny Island 4248U. (NOTE: When Sunny Boys are used in off-grid sys- tems, there are parameters in the Sunny Boy invert- ers that must also be set.

  • Page 63: Troubleshooting

    SI4248U Manual Installation Manual Troubleshooting Refer to the following table as a guide to the errors codes generated by the Sunny Island 4248U. Name Cause Release Description CBT-Open T >= 70 T < 70 Battery temp-sensor cable broken ° ° CBT-Short T <= -40 T >...
  • Page 64 Troubleshooting SI4248U Manual Name Cause Release Description NoMaster Splitphase configuration no master found (on slave device) NoSlave Splitphase configuration no slave found (on master device) RelayFail VacInverter Automatic Relay Failure VacGenreator acknowledge. Restart TBatHigh BatTemp > BatTemp < Battery temperature too high TBatMax TBatMax-2°C TR-TempOV...

  • Page 65: Battery Management

    SI4248U Manual Installation Manual Battery Management Charging Operations used by the Sunny Island The battery management system allows automatic operation (without user interference required) of 3 different charging operations: • Boost Charge: fast charging operation with short generator run time for quick battery charge (to state of charge of approximately 85 ...
  • Page 66 The charge operation is finished and charge voltage setpoint goes to Float State. The Float State affects the operation of the Sunny Island 4248U only in systems with AC coupled PV (Sunny Boys) as the generator is stopped in this state and the control loop which controls the charge current is inactive.

  • Page 67: Generator And Load Shedding Control

    State transition for generator start and load shedding The mentioned time of 2 minutes is active when Sunny Island 4248U sees discharging. The 30 minutes time is active for charging or for discharging with currents less than 0.5 A per 100 Ah battery capacity.
  • Page 68 Figure 1-27 State transition for generator start and load shedding When critical state is reached (and no charge current is detected) the Sunny Island 4248U will shut down for battery protection. After that a manual restart of the Sunny Island 4248U is required.

  • Page 69: How To Set Up State Of Charge Limits

    Float state (e.g. with DC-loads only), the BMS will automatically change to boost charge operation state and will complete boost charge operation. If the generator is started manually (without influence of Sunny Island 4248U – e.g. by rope start) while BMS is in Float...
  • Page 70 (e.g. Full Charge). Sunny Island 4248U internal control loop works on the difference between actual battery voltage and current charge voltage setpoint. The output of this control loop is the current to be drawn from the generator.

  • Page 71: User Manual

    Features The Sunny Island 4248U not only provides up to 4200 W of continuous true sine-wave AC power, but is equipped with the latest features and technology to ensure that you get the most from your battery based system.

  • Page 72: User Interface Overview

    Figure 2-2 Sunny Island 4248U User Interface Options The Sunny Island 4248U allows you to connect a variety of options to it for remote metering, load control and controlling optional equipment such as a generator. The Sunny Island 4248U supports all of the SMA Control series of metering and data acquisition devices through the use of the optional “Communication Piggy Back”...

  • Page 73: Sunny Island Applications

    DC power, an inverter is needed to change the DC voltage to an AC voltage that can be used by the AC loads. This is exactly what the Sunny Island 4248U was designed to do. The Sunny Island 4248U can also function as a battery charger for charging the battery bank.

  • Page 74: Generators

    They have sophisticated starting procedures such as crank times, retry counts and exercise routines. It is highly recommended that this type of generator be used if you require that the Sunny Island 4248U start a generator automatically. Please consult your installer or system designer for generator recommendations.

  • Page 75: Safety

    SI4248U Manual User Manual Safety WARNING: There is an inherent risk of electrical shock or injury to personnel, or potential damage to the components to the system when working on and around electrical equipment. Be sure that you have read and understand the safety instructions in the front section of this manual and any other safety documentation provided with other equipment in your system.

  • Page 76: User Interface Functionality

    SI4248U Manual User Interface Functionality The functions, modes, parameters and historical data within the Sunny Island 4248U are all displayed and accessed through the user interface menu system. To navigate to the different menus throughout the interface, you will use the arrow keys and both the ESC and ENTER keys.

  • Page 77: Changing Parameters

    How Information is Displayed Information from the Sunny Island 4248U is displayed on a 2-line LCD display. As you move up and down through the menus, 2 lines of information will be visible at a time.

  • Page 78: Home Screen

    SI4248U Manual Home Screen During normal operation, the Sunny Island 4248U displays the Home Screen. This screen shows relative output power, the operating mode of the inverter, if the generator start request has been sent, fault notification and the status of the load shedding and generator relays.
  • Page 79 (24) Fault Detection Whenever the Sunny Island 4248U detects a fault it will display the error code on the home screen for 10 seconds (and then restart if AutoStart is enabled). If the error is not acknowledged within that time, and the fault was not one that caused the inverter to shut down, an E (for Error) will be displayed in the lower right of the home screen to notify the user that an error has occurred.
  • Page 80 User Interface Functionality SI4248U Manual Status LEDs The RED and GREEN status LEDs work together to provide you with a variety of status information. Refer to the following table. Operating Condition Red LED Green LED INIT (Initialization) Standby Operating Derating BLINKING Fault Table 2-3: User Interface LED Indicators...

  • Page 81: Sunny Island 4248U User Menu Tree

    SI4248U Manual User Manual Sunny Island 4248U User Menu Tree The user menus are arranged in four simple groups: Meters, Settings, Diagnose and Operation. Using the information from the previous section, each of the parameters can be navigated to and changed if needed. The following diagram shows a simple map of the parameters that are viewable at the user level.

  • Page 82: User Menu Guide

    The following tables contain information on each of the menu items available to the user in the Sunny Island 4248U. There are other items in the Sunny Island 4248U that are visible to the user, but the following items are those which do not require a password to change. Some items display information (meters) where others are operating parameters and can be changed.
  • Page 83 SI4248U Manual User Manual Range/ Name Default Description Unit BatTemp -40 - The BatTemp menu displays the battery tempera- +200 ture. °C BatState Norm, Battery state (BMS) Warn, The BatState menu displays the current state of Low, charge of the batteries. Crit BatCharge- -----,...

  • Page 84: Settings

    User Menu Guide SI4248U Manual Settings Inverter Settings (22) Range/ Name Default Description Unit VacNominal 105 - 130 The VacNominal parameter sets the nominal output voltage of the inverter. FacNominal 55 - 65 The FacNominal parameter sets the nominal output frequency of the inverter.
  • Page 85 + Sunny Island) to this value in order to pre- vent the generator from stalling. Note: If the load in the system is above this value in Voltage Mode, the Sunny Island 4248U will not switch to Charge Mode for the same reason. GenOperation...

  • Page 86: Diagnose

    User Menu Guide SI4248U Manual Diagnose System Information (31) Range/ Name Default Description Unit DeviceConfig SI4248 The DeviceConfig parameter displays the name of the device. FWVers The FWVers menu displays the version number of the firmware installed in the inverter. SerNum The SerNum menu displays the serial number of the inverter.

  • Page 87: Operation

    SI4248U Manual User Manual Operation Range/ Name Default Description Unit BatChargMode Auto, Auto The BatChargMode parameter allows you to over- Boost, ride the Auto charge mode of the inverter. Full, Auto: Inverter maintains charge automatically. Float, Selecting any of the other modes will automatically Equalize, place the inverter into that mode.

  • Page 88: Start Up

    To turn on the Sunny Island 4248U, switch the DC disconnect on the front of the inverter to the ON position. This will cause the inverter to come on and enter the INIT phase of start up. During this phase the inverter performs a series of self tests to determine that there are no faults present in the system before beginning operation.
  • Page 89 Enclosure Check the enclosure of the Sunny Island 4248U for mechanical integrity. Should there be any damages reducing the Sunny Island 4248U’s operating safety (cracks, holes, fissures, missing covers) the Sunny Island 4248U has to be decommissioned immediately! Large dirt particles should be removed from the device with a soft hand brush or a similar tool.
  • Page 90 Maintenance SI4248U Manual State Machine The following diagram shows the state relationships for the Sunny Island 4248U. FAULTS 0: OFF 5: LOCKED DC Voltage Self Test Multiple Errors or Locked INIT Multiple Errors 1: INIT Manual or Locked Acknowledge Error...
  • Page 91 SI4248U Manual User Manual Battery Management Charging Operations used by the Sunny Island The battery management system allows automatic operation (without user interference required) of 3 different charging operations: • Boost Charge: fast charging operation with short generator run time for quick battery charge (to state of charge of approximately 85 ...
  • Page 92 The charge operation is finished and charge voltage setpoint goes to Float State. The Float State affects the operation of the Sunny Island 4248U only in systems with AC coupled PV (Sunny Boys) as the generator is stopped in this state and the control loop which controls the charge current is inactive.

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