Smart Power M4 Plus / M5 Plus
4kW and 5kW Grid-tied PV Power Conversion Systems
The Smart Power M4 Plus and M5 Plus from Beacon Power are at the heart of todays most dependable grid-tied battery backup solar power systems. They offer a unique combination of around-the-clock energy security, field-proven operation, extensive performance monitoring and a compact, streamlined design.
The Smart Power M4 Plus / M5 Plus is a fully integrated, compact power conversion solution. Its outdoor-rated enclosure houses the inverter, battery charge-controller, maximum power point tracker (MPPT), AC and DC switchgear and PV ground fault protection. Installation and system commissioning are faster, easier and less error-prone than with multiple separate components and connections. When a grid outage occurs, the Smart Power M4 Plus / M5 Plus will automatically continue to provide power for the critical loads your family or business depends upon. The new front-panel status and performance display gives you a range of highly accurate real-time operational data, as well as performance history. The system also features automatic recharge
of batteries from the utility grid, and an innovative Battery Wizard, which enables the system to work with a variety of battery types, extending your backup power options and duration. Why buy only half a solar energy system? Smart Power M4 Plus / M5 Plus lets homeowners and businesses enjoy the benefits of clean electricity 24 hours a day, 365 days a year. For security, comfort, performance and value, its a smart choice. M4 Plus / M5 Plus Features 4000 / 5000 watts output @ 50C Front panel display of performance parameters Integrated, compact single-box solution Highly accurate Maximum Power Point Tracker NEMA Type 3R (rainproof) outdoor rating Standard 5-year warranty
Smart Power M4 Plus and M5 Plus Power Conversion Systems

Electrical

Continuous power rating @ 50C PV operating range MPPT control range PV open circuit voltage Input power DC input battery voltage DC input battery voltage range Continuous charge rate Battery types supported Battery temperature sensor Battery charging AC output voltage AC output voltage range Frequency Total harmonic distortion Efficiency

M4 Plus / M5 Plus

4000 VA / 5000 VA VDC VDC 110 VDC (max.) Max. array input power (DC @ STC) 4800 W / 6000 W 48 VDC (nominal) VDC 100 A (max., no AC load) AGM, gel, or flooded Included; 20 lead From grid or PV 120 VAC (nominal) VAC 60 Hz (nominal) Less than 3% 93.5 % (peak) 91.5 % / 90% (CEC rating)

General

Operating temperature range Environmental rating Enclosure Type Mounting attitude Certifications Communications Monitoring systems -20 to +50C Indoor and outdoor 3R rainproof / sprinkler-proof Vertical wall mount only UL 1741, IEEE 929, NEC 960, CSA C22.2 No. 107.1-95 RJ-11; RS485; proprietary serial protocol Interactive front panel LCD display with data logging, state of charge readouts (standard), audible alarm, Smart Power Monitor PC-based software
The Smart Power M4 Plus / M5 Plus is a truly integrated photovoltaic solution. The inverter, charge-controller, MPPT, AC and DC switchgear and ground fault protection are housed in one streamlined unit for ease of installation and operation.

Physical

Unit weight Shipping weight* Unit dimensions Shipping dimensions* 120 lbs. (54.5 kg.) 150 lbs. (68 kg.) 42" H x 16" W x 10" D (107cm H x 41cm W x 26cm D) 50" H x 22" W x 18" D (127cm H x 58cm W x 48cm D)
*Conforms to UPS and FedEx ground shipment guidelines
Additional System Components
Battery breaker Battery cabinet NEMA 4 String combiner Required (not included) Required (not included) Required (not included) The front-panel LCD display on the M4 Plus / M5 Plus provides real-time and historical information on a range of parameters, including inverter performance for the current day and over time; state of the PV array, batteries, grid, load, and more.

About Beacon Power

Beacon Power Corporation was established in 1997. We design, develop and deliver sustainable energy storage and power conversion solutions that provide reliable electric power for the renewable energy, telecommunications, and distributed generation markets. Beacon Power Corporation 234 Ballardvale Street Wilmington, MA 01887 USA Tel: 1-888-938-9112 Fax: 1-978-694-9127 www.beaconpower.com

2006 Beacon Power Corporation. All rights reserved. Smart Power is a trademark of Beacon Power. All information subject to change without notice.

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requirements and storage and operating temperatures. Additionally, The Beacon Power Battery Enclosure and DC Disconnects have an optional earthquake kit making them suitable for earthquake prone areas. String Combiner One or more String Combiners (Beacon Power String Combiner is recommended) can be located either near the PV array or next to the M5 Plus. When choosing the installation location for the string combiners, one must consider that it should be accessible in case fuses or circuit breakers within the combiner need to be replaced or reset. The combiner also acts as a means of disconnecting the PV array from the wiring to the M5 Plus. If the combiner is located outdoors, it must have a properly rated outdoor enclosure. Determining the proper location for the string combiner will be up to the installer. Locating the string combiner near the PV Array will minimize the amount of wires running from the roof, but might make checking or disconnecting the fuses or circuit breakers difficult. Roof access may be required to troubleshoot the array and to de-energize the wiring to the inverter. Locating the string combiner near the M5 Plus requires all PV Array strings to be wired to this location, while making PV module fuse or breaker disconnection and inspection easier.

PV Input

The photovoltaic or PV array is the primary energy source for the M5 Plus inverter. A PV array has varying output that changes in two primary ways: 1) The current from the array increases with increasing intensity of the sunlight on the array; and, 2) The voltage from the array decreases as the temperature of the array increases. These two effects are central to understanding how the output of a PV array will vary throughout each day and how the overall output will change on a seasonal basis. The orientation of the PV array will determine when the array will receive the most intense sunlight. Generally, in the Northern Hemisphere, a PV array will be oriented to the south at a tilt angle of between latitude and latitude minus 15 degrees (e.g. Los Angeles is at 34 North Latitudetypical tilt angles would be between 34 to 19 from horizontal. Often orientations may not be facing exactly South due to a variety of site constraints (roof orientations, tree shading, obstructions, etc.). The installer must be aware of the impact that various orientations have on system performance. Array temperature is affected by intensity of sunlight, the location (warm or cold region), and how the array is mounted (e.g. on a roof or on an open rack) Array Sizing Properly sizing the PV array is critical for the proper operation of the M5 Plus. Below are the DC input characteristics of the M5 Plus inverter. Max. Power Vdc Max Open Circuit: Input Operating Range: Max. Operating Current: Max. Array Short Circuit: MPPT Low: MPPT Nominal: MPPT High: 6000 Watts (real power, not STC) 110 Vdc Vdc 100 Amps 120 Amps 50 Vdc 60 Vdc 85 Vdc

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Backup Circuits
The key advantage of a battery-based PV system is the ability to accommodate multiple uses for the inverter. Not only can the inverter convert clean, renewable photovoltaic energy into valuable electricity, but the inverter can also be used to maintain electrical power to critical electrical loads in a home or small office when the grid fails. PV systems without batteries must shut down and disconnect from the utility during power outages to prevent the energizing of electric circuits connected to the electrical distribution system. Therefore a Smart Power M5 Plus PV system presents an added feature of backup power and utilization of the suns energy even when the grid has failed. To provide power during a grid outage, the M5 Plus has to first disconnect (anti-island) just like a PV system without batteries. It then isolates the critical loads from the grid by opening the grid contactor. Finally, the M5 Plus reenergizes the system output to provide power to the critical loads. The M5 Plus does this in just 32 milliseconds, providing seamless power operation for almost all types of loads, including most computer systems. To ensure that the M5 Plus system will yield an adequate amount of time to back-up the critical loads, it is important to keep these loads within the capabilities of the M5 Plus output characteristics. The M5 Plus is capable of producing 5kW (42 Amps @ 120V) of continuous and up to 7.5kW (62.5 Amps) of surge power. The critical load portion of the system is considered by the National Electrical Code (NEC) to be an Optional Standby System covered by Article 702 in the NEC. This requires that all critical loads must be wired into a separate sub-panel for connection to the standby output of the inverter. NEC Article 702Optional Standby Systems allows sizing based on supply of all equipment intended to be operated at one time (NEC 702-5). This means that all the 120-Volt loads could be run off of a singlepole 50-amp breaker from an optional standby system as long as the actual continuous load is below the 80% limit for continuous operation of a standard breaker (40 Amps). Types of Loads: It is important that the installer works closely with the customer to prioritize the electrical loads to run on the backup system. Most customers would prefer to operate ALL their electrical loads in the event of a utility outage, but generally a battery system to do this is prohibitively expensive for most homes and offices. Developing a priority list of electrical loads, along with detailed power consumption information for those loads, is of primary importance for the proper operation of a backup system. Loads like central air conditioning systems or electric water heaters and electric stoves typically consume too much power to operate on a modest inverter system. Although these large electrical loads are not run off backup systems, they are also loads that are generally less critical to the customer. Loads such as lighting, gas/oil burners, furnace fans, entertainment equipment, computers, and refrigerators consume much less power, but offer substantial benefit during a power outage. This is why the priority list must include the need for the appliance in the event of an outage as well as the power consumption of the appliance. Detailed information may not be available for the power consumption of different electrical loads. When this information is lacking, an alternative is to make actual measurements at the customers site. First, the circuits must be identified that serve the most important loads. This can be done with the help of a circuit breaker finder or by simply turning off individual breakers until the proper circuit is identified. Design Considerations The first design consideration is the total continuous load which could be applied to the critical load sub-panel if all connected circuits were run at once. Should a combined total of 6000 Watts of load be connected to the output of the system and all these loads run at the same time the system would be overloaded and shutdown. When connecting loads to the critical load sub-panel it is important to follow

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Load Calculations To make the load calculation and battery bank sizing simpler, please use the worksheet provided in the Appendix. The spreadsheet in Excel format may be obtained by contacting Beacon Customer Service: service@beaconpower.com. This section will use examples to explain the worksheet.

Battery Sizing Worksheet

Continuous Continuous Surge Amps Run Watts Amps 6.00 4.00 6.00 5.00 9.32 0.63 0.15 31.1118.3731 Surge Watts Estimated Run Hours Wh's kWh's 0 0.0 0.2.88 1.92 1.44 2.40 0.00 0.56 0.00 0.04 0.11
Load (Circuit) Circuit 5: TV, Lights, Living Room Outlets Circuit 9: Refrigerator Circuit 14: Home Office, 2 Bedroom Outlets Circuit 18: Furnace Fan 1.5 HP Well Pump Misc system losses Inverter Tare Loss Total:
Backup Loads in kW/h 9.34 Power Electronic Efficiency Factor 0.90 Backup Loads in kW/h 10.38 Desired days of autonomy 0.5 Load battery must support in kW/h 5.19 System Voltage 48.00 Load battery must support in Amp/h 108.16 Allowable battery DOD(depth of discharge) 60% Battery charge/discharge efficiency 80% Battery size to support load in Amp/h 225.33 Table 1: Calculation worksheet for backup load capacity 120/240 Volt appliances When making load calculations for a new construction simply use the value of each device that is to be run through the critical load panel. Slightly different would be the design approach for a retrofit installation, where the M5 Plus is installed in an existing home. The upcoming example will be based on a retrofit installation and therefore refer to loads as circuits. In either case loads or circuits may be substituted for one another. Start by determining the continuous load on each circuit. The continuous load can be found by operating the electrical loads in the house or office in the same way as is typical of the heaviest usage. For a typical home, this is the evening when lights are on, televisions are being watched, computers are being used, and kitchen circuits are most heavily loaded. Turning ON all the loads that would be operating during such a situation can simulate this. With the help of a clamp-on ammeter, the most important circuits can be tested for their actual current flow. This is often the simplest and most reliable method of determining the electrical needs of the proposed backup circuits. Step 1: Make a list of the circuit or load currents and enter them in the column labeled Load (Circuit) and Continuous Amps. Step 2: Multiply the Continuous Amps by 120 Volts to obtain the Continuous Run Watts Value and enter this in the appropriate column. The total Run Watts should not exceed 5kW.

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Step 3: If any loads have starting surge currents multiply these by 120 Volts and enter them in the column labeled Surge Watts. Add the surge watts minus the continuous watts for that load to the continuous load total, and make sure that it does not exceed 7.5kW. Step 4: Determine the estimated amount of hours per 24 hour period that each load will be running, and enter it in the column labeled Estimated Run Hours. Step 5: Enter the Desired days of autonomy in the appropriate field. Step 6: Enter the allowable battery DOD (depth of discharge) in the appropriate field. By default this value is set to 60%. 240 Volt Applications The output of the M5 Plus is 120 Volts AC and can power most household 120 Volt appliances. Occasionally a homeowner has a critical load that is 240 Volts AC such as a water pump. 240 Volt water pumps range in sizes from to 5 horsepower (hp). The starting current of water pumps varies. It is important that the actual starting current requirements be obtained from the pump manufacturer. Pumps that incorporate starting capacitors often have much lower starting currents than those without capacitors. Without detailed starting current information, it is wise not to attempt to power pumps larger than 1.5 hp due to the high starting currents generally required by larger pumps. Should it be necessary to run a 240 Volt application on the back-up circuits of the M5 Plus, a step-up transformer, also called auto-transformer will be necessary. Remember to double the 240 Volt current requirements when calculating the 120 Volt load capacity. For example an appliance that operates 10 Amps at 240 Volts will require 20 Amps at 120 Volts. Multi-Wire Branch Circuits It is common for dwellings to have pairs of 120 Volt circuits fed by single 240 Volt, 3-wire circuits. This configuration is referred to as a multi-wire branch circuit by the National Electrical Code (NEC) and is installed to reduce the cost and labor of wiring the many circuits required by the NEC. However, this presents a problem for backup inverters operating at 120 Volts. Multi-wire circuits supply a single neutral wire for two 120 Volt circuits. This is allowed due to the fact that the neutral currents cancel one another on two 120 Volt circuit derived from opposite sides of a 120/240 Volt service panel. For instance, if one of the two circuits is drawing 12 Amps while the other circuit is drawing 8 Amps, the neutral current will be 4 Amps (12 Amps 8 Amps = 4 Amps). However, if the circuits are derived from the same 120 Volt bus, as in the case with the output of the M5 Plus, the neutral currents add rather than subtract causing a 20 Amp load to flow in the neutral. This can cause dangerous overloading and eventual failure of the neutral conductor. Sometimes high priority circuits of a customer are found to be on multi-wire circuits. There are only two options available if those circuits are to be powered with the M5 Plus. The first option is to run new circuit wiring to the point where the multi-wire circuit is split. This can be difficult and time-consuming depending on the access available to these circuits. The second option is to install a 120/240 Volt step-up splitphase transformer. The transformer supplies the needed opposite phase 120 Volts to the 3-wire circuit allowing the 120 Volt inverter to power these circuits safely. Do not use an autotransformer for this purpose.

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Battery System (48Vdc)
Battery Basics Battery systems complement the performance of a PV system in several ways. Two key ways they provide benefit are (1) by supplying a reserve of electrical energy in the event of a utility outage during cloudy periods or night, and (2) by supplying surge currents for the appliances at stable voltages. Without batteries it would be impossible to operate critical loads when refrigerators or pumps require starting current in excess of the array output. There are many types of batteries on the market. The type of battery to select depends on the application. A PV standby system operates in a similar way to an uninterruptible power supply (UPS) for computer systems. Just as with a UPS, the PV standby system should maintain the battery at a full state of charge to keep the largest possible energy available in the case of a power outage. UPS Battery capacity tends to be much smaller than for stand-alone PV applications because the amount of battery autonomy needed is generally less than for a stand-alone system. As with a UPS system, power is needed virtually instantaneously to ensure that no loss in power is experienced by electronic equipment. A standard UPS designed for computer use will have a transfer time of about 1 cycle or 1/60th of a second. Although the M5 Plus transfer rate is not quite this fast, it is fast enough to keep nearly all available computer equipment fully operational in the event of a utility outage. The type of battery most commonly used in a UPS is the absorbed glass mat or AGM battery configuration. This special type of lead acid battery is classified as a Valve-Regulated Lead-Acid (VRLA) battery. Some refer to these batteries as sealed batteries, as they are sealed with a pressure vent that minimizes oxygen from entering, and opens when they are improperly overcharged, preventing rupture. The two main types of VRLA batteries are AGM and Gel. Flooded Lead-Acid batteries are also used in standby systems, mostly due to their relatively low cost. Most common are batteries designed for service in motive applications: forklift, sweeper, and golf cart. These motive batteries have excellent deep discharge capabilities and are well suited for the type of cycling which occurs in stand alone systems. They are not well suited for standby applications because their self-discharge rate increases at full charge and is much higher than the self-discharge rate of VRLA batteries, especially AGMs. This means that a typical flooded battery will consume more energy to maintain full charge than an AGM VRLA. It is generally recommended that the storage battery system consist of maintenance-free valve-regulated lead-acid VRLA batteries with AGM or Gel construction since these require little maintenance by the homeowner. Other types of batteries may become available in the future that are equally suited to this application, but do not attempt to use any battery that has not been thoroughly tested in Uninterruptible Power System (UPS) or stand-alone applications. Always refer to the battery manufacturer for additional uses / applications of their batteries. Sizing the Battery System The M5 Plus is designed to operate with a 48 Vdc nominal battery bank. Batteries must be in a charged condition when initially connected to the M5 Plus. The batteries should be installed in a dry, wellventilated location, and away from excessive hot and cold temperatures. The amount of time critical loads can operate depends on the amount of power they consume and the size of the battery system. The amount of energy stored in the batteries will, to a large degree, determine the length of time critical loads will run. To size the battery the amount of back-up power required should be calculated by using the Load Calculation spread sheet in the Appendix (explained in the Backup Circuits Section and Table 1). Put simply, loads are multiplied by time and added up. A typical backup battery system will be sized to operate at around 1 kW continuous load which is the average usage for a home that is not running an air

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flames in area when equalize charge is occurring. When battery equalize is finished the unit will continue to operate in normal charging mode. Annual Battery Maintenance With the system shut down and the battery breaker open (disconnected), check for loose battery terminal connections by gently but firmly moving the cables back and forth perpendicular to the fastening bolt or stud. If the connection moves with minimal effort, then the connection should be unbolted, cleaned, and refastened to the proper tension. The terminals should be coated with petroleum grease or another compound recommended by the battery manufacturer and a torque wrench should be used to ensure that they are tightened according to specifications. Battery Charging The M5 Plus maintains the battery at full charge in preparation for a utility outage. In a typical gridconnect situation the batteries are at float charge voltage only for about 30 minutes each morning. After about 30 minutes the charger will lower the voltage to standby-voltage, saving energy for the rest of the day. This ensures that the battery is fully charged each day but also allows the battery to rest the remainder of the day. This also substantially increases the battery life. After the M5 Plus experiences a utility outage the batteries are recharged by PV and utility power as soon as the utility has returned. During a prolonged power outage the M5 Plus will use any PV power which is in excess of load requirements for battery charging. It is possible to end a power outage with charged batteries in cool sunny weather. Battery Equalize NOTE: Battery Equalize instructions depend on brand and model of battery used in the application. Please refer to battery manufacturers instructions for details. Generally only flooded lead acid batteries should be equalized. Perform equalization only if the full process is well understood, otherwise have only qualified personnel perform equalize charge. Equalize charge on batteries, which is basically an overcharge, is necessary to overcome two battery aging phenomena. The first is sulfating, where the plates within a battery cell that react with the acid, create lead sulfate or hardened spots. These hardened spots decrease the capacity within the given cell, and decreases overall battery system life time. Equalize charge will reverse the sulfating process to clear up the plates, and attempt to bring each cell back to the same capacity. The second is stratification, where the acidic liquid within each battery cell separates into different layers of acid concentration. Generally the bottom becomes more acidic and the top less acidic. When this happens uneven plate usage occurs which may decrease the overall battery system life time. Equalize charge will create gassing which remixes the acidic liquid, making the solution more uniform. Items needed for equalize are: Eye protection (sealed protective goggles) Skin protection (use clothing that you dont care for as acid may burn holes into fabric) Rubber gloves Baking soda Warm water and soap (for cleanup purposes only) Hygrometer Distilled water (for refilling battery cells) Before Equalizing batteries make sure that they are fully charged with no load drawing from the battery system. Add distilled water to each cell within battery system to the level recommended by the manufacturer. Generally there is a fill line on the inside of the cell opening. The idea is to cover the top

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Caution: Remember any connections made to the supply side of the utility panel will be live unless the utility meter has been removed. Check if the main input breaker to the service panel has double lugs on the supply side. If it does not, check if a double lug circuit breaker is available for that specific service panel. You may use the second unused lugs as the connection point of the M5 Plus. If you cannot find a double lug breaker, consider an insulated distribution terminal block that is wired prior to the input of the main breaker. If space permits, use a wiretap to connect directly to bare supply side wires. Check if the utility meter has double lug inputs, if not, see if one is available. Generally the utility meter is replaced by the utility shortly after a grid connected PV system has been installed. If this is the case, you may upgrade the utility meter system with a double meter, where the second meter is used to connect the M5 Plus. This will also allow keeping track of the excess power production of the M5 Plus. AC Disconnect Many utilities across the U.S. require a utility accessible AC disconnect between the M5 Plus and the final utility connection. Accessibility often means that it must be in close proximity to the utility meter at a residence. Occasionally utility meters are read remotely so the disconnect may need to be located in a more accessible location than the meter location. This AC disconnect can be the NEC required maintenance disconnect as long as the inverter is also in close proximity to the switch. Utilities throughout the U.S. are fairly similar in their specifications that this switch have: 1. visible blades that are clear when the switch is open (circuit breakers do not have visible blades). 2. the ability to be locked in the open position (the specification may include a 3/8 shank lock). In residential systems the switch may be used by maintenance personnel other than the utility, and therefore must be load-break rated (must be switch able under power). Make sure that it is properly listed for the maximum voltage and current of the application.

Figure 6: Mounting bracket alignment
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The mounting holes on the lower flange of the power unit do not carry significant weight, but they prevent the unit from pulling away from the wall or lifting upward off the mounting bracket. Install three lag bolts in the middle and end holes on the lower flange (Figure 7). Mounting the Smart Power M5 Plus is complete.
2 x 1/4" Lag Screw Holes spa ced 16" O.C.
Figure 7: Lower Flange Mounting Holes

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ELECTRICAL CONNECTIONS
The electrical connections to the M5 Plus are made in the bottom compartment of the unit after removing the false front cover. Figure 8 shows an overview of the bottom compartment, including the disconnect switches, LED indicators and Communications port. CAUTION RISK OF SHOCK. When removing and reinstalling the false front after wire connections have been made, all power sources to the M5 Plus MUST be turned off externally, including the battery and PV sources.

Front Cover

50 amp DC Circuit Breakers (3) GFI Circuit Breaker

LED Indicators

False Front
50 amp AC Circuit Breakers (3)
Communications Port (RS 485)
Figure 8: User circuit breaker compartment and false front To get to the terminal compartment where all connections are made, the false front cover has to be removed.

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False Front Cover Removal Instructions
1. Open the front cover and push it backward to hold it open 2. Remove the 8 screws marked with the symbol 1 as shown in Figure 9. 3. Pull the two bottom corners outward, making sure to clear the LEDs and circuit breakers. 4. Slowly pull the false front downward and remove.

False Front Cover

Bottom Plate
Figure 9: False front screws: 1 Bottom plate screws: 2

Conduit Connections

All wiring and cables connected to the M5 Plus must run through conduit, except for the communications wire. It is recommended that metal conduit (EMT, rigid, or liquid-tight with metal jacket) be used. Refer to NEC code for proper wire and conduit size. Holes for conduit may only be punched. The drilling of holes into the switchgear compartment may cause metal chips to affect electronic components, and will void the warranty. Drilling may only be done to the bottom plate after it has been removed from the M5 Plus. Side and rear panel entry will void the warranty since it affects the outdoor rating of the M5 Plus.

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See Figure 9 for removal instructions of the 7 screws to remove the bottom plate. The screws are marked with the symbol 2. Once the plate is removed, punch the necessary holes for the conduit connections

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Switchgear and Terminal Compartment

After the false front has been removed, the connection terminals and internal switch gear becomes visible. See Figure 10 for detail.
DC Circuit Breakers (3) GFI Circuit Breaker Battery Negative Terminal Battery Positive Terminal Battery Ground Terminal Input: DC Negative Terminals (3) Input: DC Positive Terminals (3) PV Ground and Ground Rod Terminals (2) Communications Jacks (2 x RJ-11) Battery Temperature and Current Sensor Terminals Auxiliary Relay Terminals Inverter Output Circuit Breaker Grid Circuit Breaker Load Circuit Breaker
AC Load Terminal AC Grid Terminal AC Ground Terminal AC Neutral Terminal
Figure 10: Switchgear compartment overview

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AC Connections
The terminals provided for making the AC connections contain the following size and torque specifications: Terminal Wire Size Torque Grid Hot 6 or 4 AWG 45 in-lbs (5.1 Nm) Grid - Neutral 6 or 4 AWG 35 in-lbs (4.0 Nm) Load Hot 6 or 4 AWG 45 in-lbs (5.1 Nm) Load - Neutral 6 or 4 AWG 35 in-lbs (4.0 Nm) Ground 6 AWG 45 in-lbs (5.1 Nm) Table 2: AC terminal information AC wiring must be copper. Use #6 or #4 AWG cable rated for 75 C such as THWN. The largest wire diameter accommodated by the AC terminals is #4 AWG. Increase wire diameter for long distances and use a reducing lug to meet the #4 AWG terminal. The AC output neutral conductors are not connected (bonded) to the chassis (ground). System grounding, as required by articles 690-40 through 690-43 of the National Electric Code, and ANSI/NFPA 70, is the responsibility of the system installer. All installations must comply with local and national electrical codes and standards. Refer to the SYSTEM GROUNDING section for more information.

Load Connection

Connection of the sub-panel circuit on the M5 Plus is shown in Figure 11. The hot line is connected to the load terminal, the neutral to the common AC neutral terminal, and the ground wire to the shared ground lug.
Grid Terminal Load Terminal AC Neutral Terminal
Figure 11: Grid and sub-panel load connection The sub-panel does not need to have a separate main over-current disconnect, since this is provided by the 50A circuit breaker inside the M5 Plus. All dedicated circuits for the backup loads should all be wired to code, and need adequate over-current protection dependent on the current carrying conductor. Should it be necessary to power a 240 VAC load, wire the transformer to one of the outputs of the critical load sub-panel. NOTE: Multi Wire Branch Circuit Some existing circuits may be wired with a multi wire branch circuit. As discussed in the System Planning section, multi wire branch circuit needs special attention when used to connect to the critical load subpanel. If you should need to wire multi wire branch circuits, you will need to install a 120/240 Volt step-up split-phase transformer.

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OPERATION
This section will cover important operational information about the Smart Power M5 Plus. This includes instructions for initial power up and functional performance tests, to make sure that the M5 Plus was properly installed and is fully functional for the end user application.
SYSTEM CONFIGURATION (SETUP)
Should the need arise to alter certain setpoints, in case the PV array or the battery bank differ from default recommended equipment, you will need the optional monitoring package. At this point, the monitoring package is Windows based and will require a computer, preferably a laptop running Windows 98, 2000, or XP. Refer to monitoring package for setpoint adjustment instructions.

INITIAL POWER UP

After the installation has been completed, the M5 Plus is ready for the Pre-power up Measurements followed by the Initial Power Up. Please refer to the Functional Performance section for full functionality tests. The initial testing should be performed with the false cover of the wiring compartment removed. Have all loads from the AC sub-panel disconnected, and use a small test load such as a lamp for connection to one of the branch circuits of the sub-panel. Warning Use extreme care when making measurements of, or near, live electrical circuits. Insulating gloves and eye protection are required. Warning Risk of Shock. Before replacing or removing the inner cover of the wiring compartment, disconnect all power sources from the M5 Plus: open the AC branch circuit breaker, the battery circuit breaker or pull-out fuse disconnect, and pull the fuses from the photovoltaic array string combiners (if possible). Use extreme care if the PV array wiring into the chassis cannot be de-energized. Never leave the unit or the external disconnects unattended with the lower wiring compartment open and the inner cover removed. Pre-power up Measurements: A number of measurements should be made before turning on the unit for the first time to ensure proper operation. DO NOT TURN ON ANY BREAKERS TO THE UNIT. Please measure these items and record them and make sure that they fall within the allowed window. For DC voltage values, make sure that your POLARITY READS POSITIVE! Negative readings may suggest reversed connection and can lead to damage to the unit. 1. Battery Voltage (at external breaker DO NOT TURN ON) a. Plus to minus V b. Plus to chassis V c. Negative to chassis mV 2. PV Input Strings (3 locations) a. Plus to minus (3 locations) V b. Plus to chassis (3 locations) V c. Negative to chassis mV 3. Grid Input (with external grid turned on and grid breaker in unit off) a. Hot to neutral V b. Hot to chassis V c. Neutral to chassis mV READING ________ ________ ________ ________ ________ ________ ________ ________ ________

Now that all inputs have been measured you are ready to power up your inverter for the very first time.

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Initial Power up Step 1 Turn on the battery breaker. When DC is applied to the inverter, the top LED (RUN indicator) blinks red for one second, followed by eight flashes of all three LEDs as the unit performs a self-test. The LCD display will show the initialization screen that contains the software version. The inverter should then start in Stand Alone mode; and the transformer will hum. The RUN LED will now blink GREEN once every two seconds. The LCD display will show the TODAY screen. If this does not happen, test for the presence of battery voltage (nominally 48 volts DC) between the battery positive and negative connections on the left side of the wiring compartment.
Battery Positive Terminal
Battery Negative Terminal
Figure 15: Battery voltage measurement location If the batteries are extremely discharged (less than 44 volts), the inverter may not start, and if completely dead (less than 30 volts), the LEDs may not flash. Charge the batteries to 48 Volt minimum. Use a 12 or 24V charger to individually charge batteries. Step 2 Test PV input. This test must be performed when the PV array is illuminated. Ensure that string combiner fuses are in place. Optional: Check DC input voltage on the PV sub-arrays, between each PV breaker connection and the common PV negative terminal block; PV open circuit voltage should be observed: 75 to 110 Vdc, depending on module type. A dead sub-array indicates a wiring or fuse problem associated with one of the modules.
PV + Input 3 PV + Input 2 PV + Input 1 PV - Terminal
Figure 16: PV input measurement locations Turn on the four-gang PV input breaker. Within about 15-20 seconds, the DC contactor should close with an audible click, and as the PV Power increases, the yellow PV indicator LED will flash. If the PV gang breaker immediately trips, there is a DC ground fault either in the PV array or the battery wiring. Find and correct the fault before restarting the startup procedure.

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Step 3 Turn on the INVERTER OUTPUT and LOAD AC breakers (and main breaker in the AC subpanel, if present). Connect test lamp load to a branch circuit of the AC sub-panel; lamp should illuminate. Optional: Check AC output voltage between LOAD breaker connection and NEUTRAL terminal block; this should measure approximately 120Vac.

AC Neutral Source

AC Load Hot Source
Figure 17: Load measurement location Step 4 Test utility parallel operation. Leave the INVERTER OUTPUT breaker ON and the test lamp connected to the sub-panel. Turn ON the M5 Plus branch circuit breaker in the main distribution panel, and then turn on the GRID circuit breaker. Within about 15 seconds, the green UTILITY indicator LED will illuminate, and within a few more seconds the utility contactor will close with an audible click, as the M5 Plus goes to Grid to Load mode. The test lamp will remain illuminated, with perhaps a brief blink at the transition. The RUN LED indicator will be completely OFF at this time, as the inverter itself is off-line. After five minutes, if there is sufficient PV power available, the M5 Plus may begin to export power to the utility, and the RUN LED will start to flash green. The LEDs duty cycle (i.e., ratio of OFF time to ON time) indicates the amount of power being exported to the utility line. CAUTION: DO NOT REPLACE OR REMOVE THE FRONT COVER WHILE THE UNIT IS IN OPERATION OR EXTERNAL POWER IS SUPPLIED TO THE UNIT. USE THE SHUTDOWN PROCEDURE LISTED ON THE NEXT PAGE TO TURN OFF ALL POWER TO THE M5 PLUS. THEN TURN OFF ALL POWER EXTERNAL TO THE UNIT. THIS INCLUDES AC PANEL BREAKER, DC BATTERY DISCONNECT, PV STRING BREAKERS OR FUSES. ONLY AFTER THESE ARE TURNED OFF REPLACE OR REMOVE THE FALSE COVER.

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Figure 19: M5 Plus Display Menu Tree Basic operating values can be read to give an overview of how the M5 is performing. For detailed analysis it is recommended to use the supplied PC based Smart Power Monitor software. The following explains each screen and display variables on the LCD screen.
TODAY : # #. # k WH EXPORT # # # # WA T T S BATT SOC # # # % BACKUP I NFO
TODAY Screen: TODAY ##.# kWh todays AC kWh production from PV; value resets at midnight EXPORT amount of power currently exporting from the inverter BATT SOC Battery estimated state of charge. Initially this may read ??? %, since it may take the system a full charge cycle to determine the SOC.

0 hours

5 hours

10 hours

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BACKUP Screen: This screen gets triggered when the grid fails. VBAT battery voltage LOAD output power of inverter in Watts TIME bar graph of estimated amount of time left to run the given load from line 2. This may be helpful for the user to understand when to shed his/her large loads. When the load increases, the backup time decreases. When the load decreases, the backup time increases.
I N F ORMA T I ON MOD E : EXPORT TOTAL kWh # # # # # # # HOME NEXT
INFORMATION Screen: MODE this shows which of the 4 modes the M5 is in: OFF STAND-ALONE GRID-TO-LOAD EXPORT TOTAL kWh lifetime export AC kWhs produced from PV. This value does not increase when system is in Stand-Alone mode
BATTERY : VOL TS # #. # T EMP + # # C AMP S + # # # E S T SOC # # #% MO D E PR E V I OUS NEXT
BATTERY Screen: VOLTS battery voltage TEMP battery temperature in degrees Celsius measured by the battery temperature sensor; value may be negative AMPS amperage going into or coming out of the battery. If value is positive (+) then battery is charging. If value is negative (-) then battery is discharging. It is normal to see some small fluctuation when battery is fully charged EST SOC estimated state of charge of battery; initially this value may read ???, since it may take the system a full charge cycle to determine the SOC MODE the charge mode of battery charger. Float, Bulk or Equalize.
VOL T AMP WA T T PR E V I OUS N
S # # #. # S # # # S # # # # EXT
PV (photovoltaic) Screen: VOLTS voltage of the PV array, when no sun is available this value will display battery voltage AMPS current coming from the PV array WATTS power coming from the PV array

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GR I D : FRQ # #. #
S # # #. # S + # # # S + # # # # EXT
GRID Screen: VOLTS grid voltage FRQ grid frequency in Hertz AMPS current going into or coming out of the grid. If the value is positive (+), current is flowing towards the grid or other loads in the home. If value is negative (-), current is coming from the grid to help feed the homes loads. WATTS amount of power going into or coming out of the grid. If value is positive (+) then the value depicts the amount of power going towards the grid minus the power the critical load is using. If value is negative (-) then the value depicts the amount of power coming from the grid to support the critical loads or charge the batteries.

LOAD : FRQ # #. #

VOL T AMP WA T T PR E V I OUS F
S # # #. # S # # # S + # # # # AUL T S
LOAD Screen: VOLTS voltage supplied to critical load either by the M5 inverter output voltage when in StandAlone Mode or equivalent to grid (when available) FRQ frequency supplied to critical load either by the M5 inverter output voltage when in StandAlone Mode or equivalent to grid (when available) AMPS current going to / consumed by the critical load WATTS power going to / consumed by the critical load

FAU WR CA S

FAULT Screen:

L I L I

T : COD T E D OWN L FOR SE L ENCE
E # # # # CODE # RV I CE HOME
CODE #### four digit fault code; for interpretation see Appendix SILENCE if fault occurred and Alarm is beeping then the LEFT button may be pressed to turn off the Alarm. The word SILENCE will then change to PREVIOUS

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LCD Menu Equalize
CAUTION: EQUALIZE CHARGE DOES NOT HAVE TO BE PERFORMED ON ALL BATTERIES. GENERALLY VRLA BATTERIES SHOULD NOT BE EQUALIZED. FOLLOW BATTERY MANUFACTURERS INSTRUCTIONS FOR EQUALIZE SETTINGS AND PROCEDURES. DO NOT EQUALIZE BATTERIES UNATTENDED. ALLOW PROPER VENTILATION WHEN PERFORMING EQUALIZE CHARGE AS FLAMABLE GASES MAY BE PRESENT. DO NOT SMOKE OR ALLOW A SPARK OR FLAME IN VICINITY OF BATTERIES. The Equalize Menu (Figure 20) can be accessed by pressing and holding the LEFT and RIGHT button simultaneously for 10 seconds. Should the Equalize Menu not come up immediately, navigate to the TODAY screen and try again.