Z21 SERIES HYBRID GENERAL BATTERIES. Q: Can this be used as an Off-Grid inverter?

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1 Z21 SERIES HYBRID Q: Can this be used as an Off-Grid inverter? A: A Z21 is not designed to work solely as an off-grid inverter. The off-grid function is delivered via emergency backup output when the grid is down. Q: What happens if the unit overloads? Will it stop, will it restart? If so, how many attempts will it try to clear a fault? A: An overload will trigger the protective shutdown of the inverter. The inverter will restart in 1 second. The boot up time is 30 seconds. The overloading factor is 1.5 with 10 seconds tolerance. Q: Can the inverter achieve zero feed-in to grid? GENERAL A: Yes. The Z21 has zero feed-in to grid capability. This is achieved via a simple setting on the iphone/android app Z21Manage. Z21 will behave as this: The surplus electricity will be channelled to charge the battery whenever Local load is less than PV output. The inverter will reduce its output power to maintain the zero feed in to grid after the battery is full. Q. Can it be connected into a 3 phase system? A. Yes. Z21 is a single phase unit, it will however operate correctly on any phase. BATTERIES Q: What is the battery discharging capacity? A: 100A / 4.6kW Q: How many battery modules will fit into the battery cabinet? A: The maximum is 4 modules for the current cabinet

2 Q: What is the IP Rating of the battery module and enclosure? A: The battery cabinet is rated IP20 and the battery module is rated IP50. Q: Does the battery have galvanic isolation from AC & PV? A: The battery has galvanic (electrically) isolation from AC and PV by isolation transformers. Q: What is the battery charging capacity? A: The maximum power that can be charged to the battery each day (P) is 4.6kW x (H) per Z21. Assuming H (Solar hours) = 4, then P= 18.4kWh per Z21. Only the surplus power from Z21 is used to charge the battery. A: The maximum battery charging current is 0.15 x battery bank capacity (to a maximum of 50A). Q: Parallel Operation - is it possible and will each inverter look after its own battery bank? A: Yes. By design the number that can be connected is not limited to three. Here are a few key points to note for parallel connection situations: Q. Can a non-zeus Appollo lithium battery pack be used? The total Battery Capacity set in all the Z21 combined must be the actual battery bank capacity. For example, the battery bank capacity is 45kWh and is connected to 3 x Z21 inverters, then the Battery Capacity in each Z21 is to be set to 15kWh. Only Lead Acid battery can be used in this parallel connection. Lithium battery cannot be used in this parallel connection. A. The non-za lithium battery factory will need to know the communication protocol of the Z21 and make their BMS compatible with the EZ Converter before the non-za lithium battery packs could be used with the Z21.

3 Q: What does the battery charge curve look like? A: The Z21 provides 3-stage charging to lead acid batteries. The user manages the battery via the Android/iOS app by entering the battery details into the app itself. The charge chart looks like this: 1. Stage 1 Constant current charge. 2. Stage 2 Constant voltage charge. 3. Stage 3 Float charge (or trickle charge). Q: What batteries can be used with the Z21? A: The Z21 can be used with both Lead-Acid and Lithium battery packs. If using Lithium batteries, it is recommended to use our BMS (Battery Management System) to improve the lifetime and management of the batteries. A: A purpose designed LiFePO4 battery module has been developed for use with the Z21. It has an integrated BMS to work at maximum capacity and longevity with the Z21. PERIPHERALS Q. What is the EzConverter? A. This is the communication gateway between the inverter and the lithium battery BMS. One EzConverter is used per inverter and can communicate with multiple lithium battery packs. Q. What is the EzMeter? A. This device connects between the inverter and the power meter. Its purpose is to monitor the energy flow and inform the Z21 if there is feed-in taking place. Z21 will take action as to allow the feed-in or to charge the battery. A. One EzMeter is required for each Z21. A single EzMeter cannot be connected to more than one Z21 unit.

4 EMERGENCY BACKUP OUTPUT CIRCUIT Q: If the Z21 has no batteries and there was a grid black out during daylight would the PV be able to supply power to the backup AC circuit? A: Yes. The backup AC output circuit can deliver power to the local circuits whilst DC power is generated through PV. Q: What is the capacity of the dedicated back-up circuit? A: 4600 Watts / 20 Amps Q: Can the back-up circuits be joined when using multiple Z21 s? A: The Back Up output from each Z21 must be separate from each other. They cannot be connected in parallel as damage may be caused by high current drain. Each Back Up output will have to be connected to different local circuit to backup different circuits. For example, No.1 backs up TV circuit, No.2 backs up lighting circuit and No.3 backs up fridge circuit. Q: If it changes from grid supply to solar supply seamlessly when the grid goes offline, how do we know, so we can reduce our power demand? Is there a warning light or something to warn us? A: You would know the grid has gone offline as the power in the house will go out. We must emphasise that it is an Emergency Backup Output Circuit ; therefore it would not be appropriate to have the whole house connected to this. We recommend wiring up some lights with low wattage bulbs, some power points to allow power to be provided to the phone and internet router along with other devices that would be essential in a blackout. In a power outage, a fault light should show warning of Utility Loss (AC Loss). Q: How do the motors in my fridge & freezer react to low power? e.g. if they're using 120 watts each while running, and something else cuts in that pushes demand over what the panels are supplying, am I going to burn out my fridge/freezer motors? A: We do not recommend wiring up your fridge or freezer to this circuit for the reasons listed in the previous question. When the compressor kicks in, for a few seconds its inductive load potentially may draw up to 3 times its normal operating wattage. If there is not enough power to run the appliance, it simply won t run. With the addition of batteries, you may be able to consider additional options such as refrigeration under this emergency backup output circuit. Prioritisation is the key to ensure you take full advantage of this backup capability.

5 Q: The Emergency Backup Output Circuit can be turned on or off under advanced settings in the Z21Manage application. Is there an alternative way to change this setting? A: Activating/deactivating is done through the settings menu in the Z21Manage app. When the installer sets up the Emergency Backup Output Circuit, they will need to turn on this setting in the application. Once this backup circuit is connected, there will be no reason to switch it off, nor would we recommend switching it on if there is no Emergency Backup Output Circuit wired to the inverter. If for some reason there is a need to stop the emergency supply of power to the house during a blackout, simply follow the shutdown procedure shown on the front of the inverter to isolate the DC and AC. Q: If you connect a dedicated circuit to the Emergency Backup Output on the inverter, will that circuit also receive power during normal operating conditions, or will it only receive power when the grid goes down? A: The Emergency Back-up output will always receive the power no matter the grid is available or not. The back-up output may get the power from the grid, solar or batteries. COMMERCIAL TOPICS Q: Has your hybrid solution been deployed in another country(s)? What standards does the hybrid inverter comply with? A: The Z21 hybrid solution has been delivered to many countries such as Great Britain, Belgium, Italy, Czech Republic, South Africa, Pakistan, Thailand, etc. The hybrid inverter meets the following standards: VDE /G83/G59/SAA/IEC62109D. Q: What is the warranty of the battery on the hybrid system? A: Currently the warranty of the battery module is 5 years; the warranty of battery cell is 10 years. Q: What considerations have you made to make the product suitable for the Australian market? A: To be suitable for the Australian market, many factors have been taken into consideration such as SAA safety regulations (voltage range, frequency range, etc.); high temperature and salt mist; grid structure to meet Western Power and other grid requirements in Australia; and EMC for whole system. EMC includes conduction and radiation.