1 General RequirementsThis SunSpec Communication Signal for Rapid Shutdown Specification defines how to propagate the shutdown state of a PV system to the individual power production components.

These general requirements apply to any PV system components and communication networks supporting the module-level rapid shutdown communication capabilities defined in relevant NEC and UL standards. General requirements are divided into categories: system configuration, application protocol, operational, and safety requirements.

Other sections of this document describe additional requirements and constraints associated with physical (wired and wireless) networks that are used to support this application.

1.1 System ConfigurationA rapid shutdown communication System is a collection of Components and Communication Protocols that are used to implement communication signaling requirements as defined by NEC 2014 or NEC 2017. Components of a rapid shutdown communication System are Initiator(s), Master(s), and Slave(s).

Communication Signal for Rapid Shutdown is designed to support module-level rapid shutdown requirements of any PV plant governed by NEC 2014, NEC 2017, or UL 1741, irrespective of plant configuration or physical network choice. Issues that commonly effect application protocol performance—including cross-talk from other protocols, noise, and line impedance—must be accounted for.

Insert Figure depicting a rapid shutdown communication System.

1.1.1 InitiatorAn Initiator is the equipment that is responsible for initiating the rapid shutdown mechanism in the System.

The term Initiator, in this context, is defined in the draft 1741 standard:

Initiator(s) – one or more manual or automatic switching device(s), input port(s) or signal(s) that will result in the activation of the rapid shutdown system function(s) to disconnect or reduce the voltage of the PV system from other conductors in the building. An initiator is intended to meet the function of the 2014 NEC defined initiator.

Requirement: A System maymust have one or more Initiators.

Requirement: An Initiator must have two states: “ready to operate” and “stop operation”

1.1.2 MasterA Master is the equipment that is responsible for transmitting a communication signal that reflects the current state of the Initiation Device. The portion of the PV system controlled by a

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single Master is referred to as a Subsystem. The minimum and maximum Subsystem supported by a single Master is manufacturer dependent and must be specified.

Requirement: A System must have onlyat least one Active Master.

Requirement: A System maySubsystem must have only one or more Standby MastersMaster.

Requirement: Every Master in the System must be connected to every Initiator, or the logically aggregated equivalent, so that every Subsystem within the System is performing in the same mode of operation.

Requirement: A Master must specify the min / max number of PV strings and min / max DC power rating for the Subsystem to ensure the transmission signal arrives across the entire Subsystem with adequate strength per receive power specifications.

[1.1.3] SlaveA Slave is the equipment that is responsible for receiving the communication signal transmitted by a Master and is capable of initiating a state change of associated power producing components based on the signal received.

Requirement: A SystemSubsystem must have at least one Slave.

Requirement: Slaves must interact with a single Active Master.

[1.2] Application ProtocolThis section describes requirements associated with application protocol behavior and network topologies.

[1.2.1] Network topologyCommunication networks supporting the Communication Signal for Rapid Shutdown specification in PV power plant systems are arranged in star-, ring-, mesh- and other topologies. Depending upon overall system requirements, cost requirements, and other operational constraints, vendors may choose to utilize one topology or another.

Requirement: The Communication Signal for Rapid Shutdown Application Protocol must be deployable in at least one network topology and may be deployed in any network topology.

[1.2.2] Network System DependenciesCommunication Signal for Rapid Shutdown is intended to assure the physical safety of personnel who may come in contact with PV modules in an operational PV plant. As such, network services, features, or dependencies that increase the likelihood of false positives or false negatives are discouraged.

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Requirement: Communication Signal for Rapid Shutdown must not depend upon proxy servers or network routing devices that could create false positive or false negative operational conditions.

[1.2.3] PV System Configuration and Noise Tolerance Communication Signal for Rapid Shutdown is designed to support module-level rapid shutdown requirements of any PV plant governed by NEC 2014, NEC 2017, or UL 1741, irrespective of plant configuration or physical network choice. Issues that commonly effect application protocol performance—including cross-talk from other protocols, noise, and line impedance—must be accounted for.Requirement: Communication Signal for Rapid Shutdown must operate within frequencies and communication channels that can be isolated from other protocols.

Requirement: Communication Signal for Rapid Shutdown must not interfere with or disable other active functions (e.g. arc fault detection, DC-DC optimization, etc.)

Requirement: Physical networks must be capable of providing Communication Signal for Rapid Shutdown for the full range of system sizes and configurations covered by relevant regulations.

Requirement: Communication Signal for Rapid Shutdown must tolerate noise levels and line impedance levels that are within accepted standards for plants bound by rapid shutdown regulations.

[1.2.1] Packet FramingCommunication networks implement the concept of “packet framing” wherein the “payload” (i.e. the data to be evaluated or processed) is surrounded or “framed” by meta information. Framing delineates the boundaries of the actionable data within a packet that is required to fulfill the application operation.

Packet Framing can be implemented on a variety of physical network media and offers the possibility of future use by other applications.

Requirement: The Communication Signal for Rapid Shutdown application protocol must implement Packet Framing.

[1.2.2] PerformanceCommunication Signal for Rapid Shutdown is designed to be “always on and always active” during timeframes specified by relevant standards.

Requirement: Networks supporting Communication Signal for Rapid Shutdown must provide bandwidth and network latency characteristics capable of meeting the functional requirements of relevant regulations.

1.1.3[1.2.3] Master/Slave InteractionsMaster/slave interactions are at the heart of Communication Signal for Rapid Shutdown operation. By optimizing for efficiency and simplicity, low-cost and reliable system solutions are possible.

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Requirement: Master must transmit a permission to operate signal to slaves when an Initiator indicatesall Initiators indicate rapid shutdown is not active.

Requirement: Master must stop transmitting a permission to operate signal to slaves when anany Initiator indicates rapid shutdown is active.

Requirement: Slave must receive communication from master, but is not required to respond.

Requirement: Slave must be able to receive a permission to operate signal and initiate the ability for the associated power-producing equipment to produce power.

Requirement: Slave must detect the absence of a permission to operate signal and initiate the shutdown of power production by associated power producing equipment.

Requirement: Master must transmit a signal every __ seconds when the Initiation Device indicates rapid shutdown is not active.

Requirement: Slave must invoke a shutdown of power production if a permission to operate signal has not been received in __ seconds.

Requirement: Master must detect a change of state of the Initiation Device within __ seconds and either transmit or suspend transmission of a permission to operate signal. (Differentiate up and down?)

Requirement: Slave must initiate the ability for the associated power producing equipment to produce power within __ seconds after receiving a permission to operate signal. (Is this a requirement of the relevant standards?)

[1.3] Operational ConsiderationsOperational simplicity is a key goal of the Communication Signal for Rapid Shutdown. Features that open the possibility to unwarranted truck rolls or other unnecessary human interaction are to be avoided if at all possible

Requirement: To provide mechanism to bring PV system back online after a rapid shutdown event, a System must support start-up activation after a shutdown.

Local regulations may add requirements for start-up activation.

1.2[1.4] Safety ConsiderationsMandatory features of the Communication Signal for Rapid Shutdown specification represent minimum functionality required to achieve NEC 2014 or NEC 2017 safety standards.

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Requirement: Communication Signal for Rapid Shutdown must support shut down in a “fail-safe” manner.

Requirement: System must energize only when Initiator mechanism is set to “ready to operate” position.

Requirement: Must conform to UL1741 Sections 87-97.

[1.5] Cybersecurity ConsiderationsCybersecurity is an important aspect of any communication system. Federal and state regulations are evolving rapidly. In the future, it is expected that every power plant that connects to the grid will be characterized in cybersecurity terms.

Requirement: Manufacturers of Master(s) and Slave devices must declare the cybersecurity capabilities of their products.

Cybersecurity is not considered for this specification.

[2] Power for Master(s) and Slaves[2.1] Power for Master(s)

To fulfill the requirements of Module-Level Rapid Shutdown regulations, the Master must remain in a powered-on state at the times it is needed to fulfill the rapid shutdown service.

Requirement: The Master may be powered by either AC or DC power sources.

[2.1.1] Power for Master(s) Supplied by Slaves (option?)

[3] A crucial requirement on a shutdown system is standby power from Modes of Operation

Two modes of operation are defined for a System: Active Mode and Shutdown Mode. Active Mode is characterized by the typical state of a PV system, generating power unimpeded by the Rapid Shutdown System. For this condition to persist, all Initiators must be set to the “ready to operate” state. If at least one Initiator is set to “stop operation” state the entire System (including all Subsystems) must enter the Shutdown Mode. Transitioning from Active Mode to Shutdown Mode was comply with overall timing constraints as set forth in NEC 2017. There are no timing constraints when transitioning from Shutdown Mode to Active Mode.

1.3 Active ModeNo specifications or restrictions are placed on PV generators during the Active (power producing) Mode. The Rapid Shutdown System must continuously monitor all Initiators for a change in allowable operating state.

1.4 Shutdown Mode

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NEC 2017 specifications require the illuminated PV generatorgenerators and complete PV system to be de-energized to a maximum of 30V and 240VA when in casethe Shutdown Mode. Instead of a missing keep alive signal. completely zeroing output power capability, it is desirable to provide a non-zero output power within the range offered as allowable by NEC 2017.

This feature brings the following advantages:

When the rapid shutdown initiator(s) are not enabled, the system must be able to restart.

[3.1.1] Reduced power consumption during the nightThe presence of the standby power gives the information of the presence of daylight. It allows to turn-off the keep alive signal overnight and reduces thereby the power consumption of the system.

1.4.1[3.1.2] Ease of installationThe installer can measure the right polarity, the count of modules per string, the string associated wires etc. without a special tool to inject the keep alive signal. He has the additional benefit of working on safe voltage levels and a limited power now.

1.4.2[3.1.3] Supply of electronicsDuring a shut downShutdown it is possible to power the keep alive circuitry (= the master, i.e. signal generator and a circuit who measures and signals the shut downShutdown operation) from the illuminated PV generator. This prevents a deadlock with purely PV powered systems. With this feature no AC supply is needed to power up the system

[3.1.4] Requirement: The output voltage power capability of a string of modulesPV system in Shutdown Mode must stay below the maximum voltage specified in theand power specifications stated per NEC in case of shut down. 2017

With typical system designs and module characteristics there will be much less than 30 modules connected in series. Therefore, an output voltage of 1 V per moduleVOFF in the sub-volt range will satisfy the NEC requirement of a maximum of 30 Volts after a rapid shutdown initiation.

The minimum current available in the shutdown state should be sufficient to guarantee operation of equipment monitoring the state of the modules. In the case of field installation measurements, a typical low-impedance type multi-meter can have a 10kΩ input impedance so the current capability of the constant output voltage should be at least 0.1mA.

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Requirement: Each PV modulegenerator must provide constant output voltage of 1V during operation.

[3.1.5] The signaling circuit can be constructed VOFF ,with low power consumption. As a consequence an output current of each module of 2 A will suffice. This power depends on the available irradiation. A higher output current of up to 4 A is allowed. (Note: Depends on requirement on max. 8 A in NEC 2017 and two parallel strings.)current compliance IOFF,MAX , when in the Shutdown state.

[3.1.6] Requirement:Optional (High Power Shutdown): Each PV modulegenerator must provide minimum constant output voltage VOFF ,with current compliance IOFFHI,MAX , when in the Shutdown state.

In the case, where offering power to upstream power electronics is desirable, higher current capability is required. Per NEC 2017, the total combined current of 2 A during operation.all parallel strings cannot exceed 8A, placing a limitation on the number of high power shutdown strings that can be placed in parallel (NSTRING <= 8A / IOFFHI,MAX)

1.5 Mode TransitionsNEC 2017 regulations allow for 10 seconds from the initiation event until the system must be fully settled in the de-energized Shutdown mode. In order to facilitate interoperability, it is important that the total time to de-energize is equitably allocated to the constituent steps of the de-energization process.

A typical de-energization process (mode transition) can be considered as the following sequence of events.

T1: Initiator relays Shutdown command to Master

T2: Master ceases to send KeepAlive Communications Signal to Slaves

T3: Slaves de-energize all PV generators

T4: Inverter stored charge is eliminated

There are no Requirement: Each PV module must provide maximum constant output current of 4 A during operation.

A typical PV string of a 600V system would provide approximate 20 Watts in shutdown mode which is suitable for powering the signaling circuit.

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PV RSE 0 V

PV RSE

Standby PowerVoltage=1 V

PV RSE keepalive signal

pv-panel voltage

In presents of sunlight the panel level rapid shutdown device feeding in of 1 V, 2 VA standby power

PV RSE

If sending of the keepalive signal is interrupted during sunlight, the panel level papid shutdown device feeding in of 1 V, 2 VA standby power

night

day

day

day

Standby PowerVoltage=1 V

Figure 1: Standby power supply by the slaves

[3.2] Power for SlavesTo fulfill the requirements of Module-Level Rapid Shutdown regulations, the Slave must remain in a powered-on state at the times it is needed to fulfill the rapid shutdown service. As the intelligence for Slave devices is embedded in the PV module, the module is the most likely source of power for Slaves.

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Requirement: Slaves may be powered by either AC or DC power sources.

Requirement: When Slave is not powered the associated power-producing equipment (i.e. the PV module) must not produce power in excess of the mandated shutdown levels.

timing requirements placed on the system with respect to a mode transition from Shutdown to Active Modes.

1.6 Mode Specification Table Symbol Mode Specification Min. Nom. Max. Unit Remark

VOFF PV Generator voltage in Shutdown TBD TBD TBD VTolerance spec includes accuracy and impedance

IOFF,MAX Maximum output current in Shutdown TBD TBD TBD mAIOFFHI,MAX TBD TBD TBD mA

NSTRING TBDMax Parallel Strings for High Power Shutdown Systems

FC Suggested Crystal Frequency TBDT1 Time for Initiator to relay to Master TBD sT2 Time for Master to stop KeepAlive TBD s

T3 Time for Slave to de-energize PV generators TBD s

T4 Time for Inverter stored charge to be eliminated TBD s

2 Power Line Communication (PLC) RequirementsInstallation A Master communicates with all PV generators in the Subsystem over Power Line Communications. The Master continuously transmits a “Keep Alive” bit sequence to indicate PV generators have permission to operate in the Active Mode. If the Master ceases to transmit the Keep Alive sequence then the Subsystem enters the Shutdown Mode. Three other bit sequences are defined and reserved for future use.

2.1 Master Transmitter RequirementsThere are no specific installation requirements.

Environmental RequirementsThe Master broadcasts a Keep Alive

There are no specific environmental requirements.

[3.3] Packaging RequirementsThere are no specific packaging requirements.

[3.4] Modulation Requirements

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Communication signal must useusing a spread frequency shiftshit keying (S-FSK).

[3.4.1] Spreading The values for the absolute frequency deviation |f_M-f_S | are should be such that the signal transmission qualities at f_Mand at f_S are independent of each other. Taking into account the measurements presented in IEC61334-1-4, it is recommended that |f_M-f_S |>10 kHz be used.

Requirement: f_M=470.4 kHz and f_S=483.84 kHz.

[3.4.2] Continuous PhaseThe phase trajectory of the SFSK signal shall be continuous for the entire duration of a KeepAlive signal transmission, including across mark-space and space-mark transitions. 

[3.5] Protocol SpecificationUsually communication packets are composed of preamble, header, and payload. The preamble is used to describe the existence of the packet, and the header is used to denote information used for packet decoding such as modulation, packet length, etc. The payload part has the actual information that is interesting. In this rapid shutdown system, since the communication is unidirectional and more importantly the information is exceedingly simple, we may use the preamble as the payload.

Requirement: The preamble packet must use the structure in Figure 2, where “1” means the FSK signal with the frequency f M and “0” means the signal at f s. Bitb i is the i-th transmitted bit from the power inverter. The two frequencies, defined in 4.3.1, are used for frequency diversity in case one frequency band (either f M or f s) is corrupted by noise and has bad channel quality. Additionally, when the channel is limited by random additive noise, an SNR improvement of 10 log1015=11.8dB is obtained by encoding the Keep-Alive message into a 15-bit sequence. M consecutive 15-bit Keep-Alive sequences can be combined in the detector to obtain 10 log10M dB additional SNR.

Figure 2 Packet structure for Keep-Alive Signal for binary information transmission only

Each bit (or equivalently the signal at each frequency) period is 5 ms. Because each packet comprises 15 bits, the total packet duration is 75 ms. Figure 3 shows the signaling diagram of the packet. From the implementation perspective, vendor dependent time domain windowing may be applied to reduce the spectral leakage caused by bit transitions. Alternatively, continuous phase FSK (CPFSK) or Gaussian FSK, may be used to reduce spectral leakage.

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Figure 3 Actual signaling diagram of Keep-Alive signal

Let d0 , d2,…,d14 represent the FSK detector output in each of the 15 bit slots in a sliding window. Assume the Keep-Alive sequence is K 1 = “100010011010111”, a choice with beneficial correlation properties. Define the Keep-Alive correlation variable to be l1=d0−d1−d2−d3+d4−d5−d6+d7+d8−d9+d10−d11+d12+d13+d14. A Keep-Alive packet is detected when l1 crosses a predefined threshold. Autocorrelation of the sequence K1 is shown in Figure4, where we see that the autocorrelation profile of the Keep-Alive signal is high when the received signal and the reference Keep-Alive signal are perfectly matched, and the correlation peaks repeat every 15 samples.

Figure 4 Auto-correlation profile of Keep-Alive signal

The preamble packet structure will also support scenarios where commands other than the simple On/Off are useful. Other 15-bit codes may be used to initiate actions other than enabling or disabling the module output. For example, while the Keep-Alive detector performs an inner product between the detected FSK sequence and reference K1=¿“100010011010111”, three additional commands can be initiated by additional detectors calculating the correlations with references K2=¿“001111110111010”, K3=¿“111001000001100”, and K4=¿“010100101100001”. These 15-bit Kasami sequences possess high

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autocorrelation peaks and low cross correlations with each other are ideal to render the protocol expandable in the future when the need for additional commands becomes apparent. Figure 5 shows the) transmitter messages for two commands. Figure 6 shows auto-correlation profile of K 2. Figure 7 shows cross-correlation profile of K 1 and K2.

.

Figure 5 A command for Keep-Alive message and another command for other message

Figure 6 Auto-correlation profile of K2

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Figure 7 Cross correlation profile of K1 and K2

[3.5.1] Shutdown mechanismWhen there is a single Keep-Alive command in Figure 2, the inverter normally broadcasts every 75 ms while the system is up and running and the solar modules generate electricity. The receiver in each module continuously listens for the Keep-Alive signal. When it is missing for I 1 consecutive periods, each module will shut down. Figure 8 shows a flowchart for this operation. When multiple commands are supported, then the inverter broadcasts the signals K 1,K2 ,…, K N in sequential order every 75N ms. Each command follows the same flow chart as shown in Figure 8. Thus, if each command does not detect its own signal within IN periods, the modules cease execution of the command.

When in Shutdown state, the receiver in each module continues to listen for the Keep-Alive signal. When the inverter sends J1 consecutive Keep-alive messages again, the modules reactivate. For fail-safe operation, J1 shall be greater than I 1. Figure 9 shows a flowchart for this operation. When there are multiple commands, each follows the same flow chart shown in Figure9.

If there are too many state changes between Keep-Alive state and Shutdown state within a certain period of time, then each solar module stays in Shutdown mode for fail-safe mechanism.

Figure 8 Shutdown mechanism when harvesting energy

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Figure 9 Reactivating mechanism when shut down

[3.5.2] Synchronization mechanismIn order to employ the command signal detection defined in section IVa, the receiver must synchronous with the transmitter frame.

For multiple command support, each packet could represent any supported command. For example, let us assume that there are two supported commands. Assume that for a certain receiver at the command decoder, the decision variables are d0 , d2 ,…,d15. Then at the receiver, define the correlation variables l1=d0−d1−d2−d3+d4−d5−d6+d7+d8−d9+d10−d11+d12+d13+d14and l2=−d1−d2+d3+d4+d5+d6+d7+d8−d9+d10+d11+d12−d13+d14−d15. The solar modules then calculate the values, l1 and l2, and decide which type of packet is being received by thresholding these values, so that the frame synchronization is done. Because the two command signals are pseudo-orthogonal, they are maximally separated. The solar modules will then decide which command is being received. If none of these variables cross a predefined threshold, then then the receiver can declare that there is no command being received.

[3.5.3] Transmitter (Master) Specifications

5.5.3.1 General Transmitter Specifications

. The transmitter must provide the receivers with signals at satisfactory level for demodulation. It must develop sufficient power on a given load impedance and must have a well-defined output impedance.

Requirement: Transmitter must transmitsend a ‘permission to operate’ signal when an Initiator indicates rapid shutdown is not active

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Requirement: Transmitter must use FSK modulation, corresponding to one of four code words defined as W1, W2, W3, W4. Code words are transmitted in the 450 – 500 kHz frequency banda repetitive cyclical fashion with no headers or time spacing in-between.

Requirement: Transmitter must have 50 ohm +- 10 ohmZOUT output impedance in the transmission frequency band

Requirement: Transmitter must provide 20 dBm -1 +3 dBmPTX output power on 50 ohm load

To assure interoperability between Rapid Shutdown systems coming from different vendors, the transmitter must have fixed Mark and Space frequencies. These frequencies should be easy to generate from widely used crystal oscillator frequencies.

Requirement: Transmitter Mark Frequency must be 470.4 kHz +- 50 Hz

Requirement: Transmitter Space Frequency must be 483.84 kHz +- 50 Hz

FSK Transmitter Specifications Min. Nom. Max. Unit RemarkTransmitter Output impedance in RF band 40 50 60 ohmOutput Signal Power / 50 ohm 19 20 23 dBm (100 mW)Mark Frequency 470.35 470.4 470.45 kHz 16 MHz / 34 +-50 HzSpace Frequency 484.79 483.84 484.89 kHz 16 MHz / 33 +-50 Hz

Table 1

Requirement: The Master must transmit Keep Alive signal using a mark and space tone frequency of FM and FS respectively

Requirement: The Master must maintain the transmission of a mark or a space tone for TS duration, resulting in an effective bit rate of RS

Requirement: The Master must maintain phase coherency when transitioning between mark and space tones

Optional: The Master may utilize a crystal of frequency FC in order to synthesize specified tone frequencies

2.1.1 Transmitter Out-of-Band Emission Requirements

The transmitter must not generate spurious out-of-band signals that could interfere with other communication systems or with PV system components like MPP tracker or AFCI

Requirement: the Out-of-Band spurious frequency components must not exceed the levels defined in Table 2 and depicted in Figure 10.

Out-of-Band Spectral Mask

F [kHz] 0 200 200420FM –

50450FM –

20500FS +

20530FS +

50 1000P [dBm] -40 -40 -20 -20 20 20 -20 -20

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Table 2

Figure 10

2.1.2[3.5.4] Transmitter In-Band Emission Requirements

To assureensure easy separation of the carriers in the demodulator, the in-band spectrum of the two FSK carriers must be limited.

Requirement: the In-Band frequency components must not exceed the levels defined in Table 3 and depicted in Figure 11.

The frequency and amplitude values are relative to the actual frequency and power of each of the two FSK carriers.

In-Band Spectral MaskF-Fc [kHz] -50 -9 -9 -5 -5 5 5 9 9 50P [dBc] -30 -30 -20 -20 0 0 -20 -20 -30 -30

Table 3

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Figure 11

2.2 Slave Receiver (Slave) Specifications5.5.6.1 General Receiver Specifications

The receiver must be able to handle a large range of input signal amplitude. Maximum amplitude is received with maximum TX power and minimum PV string attenuation, and inverselyconversely, minimum signal is received with minimum TX power and maximum PV string attenuation.

Requirement: Receiver must decode the FSK signalsignals at FM and FS as sent by the transmitter. The FSK Mark frequency is 470.4 kHz +- 50 Hz, the Space frequency is 483.84 kHz +- 50 Hz.

Requirement: Receiver must acceptdecode KeepAlive signals with a probability of at least 99% in the presence of FSK signal amplitude up to 36 dBmAamplitudes in the range IRXSENSE mA – IRXMAX mA.

Requirement: Receiver must be able to decode FSK signal with amplitudehave pass-through impedance with absolute value less than ZRX at FM and FS frequencies

Requirement: Receiver shall have a false-detection probability of less than PFALSE as low as -10 dBmAdemonstrated in conditions set forth in SunSpec Rapid Shutdown Compatibility Test Plan.

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The receiver must not attenuate excessively the FSK signal, i.e. it must have limited input impedance in the PLC band.

Requirement: Receiver must have pass-through impedance with absolute value less than 5 ohm

FSK Receiver Specifications Min. Nom. Max. Unit RemarkInput impedance in RF band 5 ohm

Max. Input Signal Current 36 dBmA(63 mArms)

Min. Input Signal Current -10 dBmA(316 µArms)

Mark Frequency 470.35 470.4 470.45 kHzSpace Frequency 483.79 483.84 483.89 kHzTable 4

2.2.1[3.5.5] Receiver Out-of-Band Rejection Specifications

The receiver must not be perturbed by signals outside the receive band.

Requirement: Receiver must rejecttolerate the presence of out-of-band signals byhaving rejection ratio values as defined in Table 5 and depicted in Figure 12., for a sensitivity reduction of no more than 3dB.

RX Out-of-Band RejectionF [kHz] 0 100 100 250 250 450FM

– 50450FM

– 20500FS

+ 20500FS

+ 50700 700 1000

RR =IRXSENSE/IOOB

[dB]

-50

-50 -40 -40 -20 -20 0 0 -20 -20 -30 -30

Table 5

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Figure 12

2.2.2[3.5.6] Receiver In-Band Rejection Specifications

The receiver must be able to separate the two carrier frequencies of the FSK modulated RF signal.

Requirement: Receiver must reject in-band signals by values defined in Table 5 and depicted in Figure 13.

Rx In-Band RejectionF-Fc [kHz] -50 -9 -9 -3 -3 3 3 9 9 50RR [dB] -30 -30 -20 -20 0 0 -20 -20 -30 -30

Table 6

Figure 13

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Transport & routing requirements/assumptions

Payload requirements

Installation considerations

Environmental

Packaging

Power

Other

These may be features that differentiate products in the marketplace, but not items for the specification.

Security requirements

Cyber security has not been considered at this time

Transport & routing requirements/assumptions

[3.6] Subparts for PLC and wirelessSpecification Table Non-routable protocol for PLC

Payload requirements (how much data)

PLC and wireless requirements

Symbol Master Specification Min. Nom. Max. Unit RemarkW1 Code Word 1 100010011010111 Keep AliveW2 Code Word 2 001111110111010 ReservedW3 Code Word 3 111001000001100 ReservedW4 Code Word 4 010100101100001 ReservedFM Mark Frequency 468.75 kHzFS Space Frequency 481.25 kHzTS Bit Period 5.12 msRS Bit Rate TBDFC Suggested Crystal Frequency TBDZTX Transmitter Output Impedance 40 50 60 ΩPTX Transmitter Power into 50Ω 19 29 23 dBm (100mW)

IRXMAX Receiver Input Current Max +36 dBmA 63 mA @99% success rate

IRXSENSEReceiver Input Current Minimum Sensitivity -10 dBmA 0.31mA @99%

success rateZRX Receiver Output Impedance @ FS 5 Ω

PFALSE Probability of false detection Per SunSpec testing

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