Product Category
Common Problem
Cause of occurrence:
Generally the PV modules, junction boxes, DC cables, inverters, AC cables, terminals, and other parts of the line to ground short-circuit or insulation layer damage, loose string connectors into the water, and so on.
Solution:
Disconnect the grid, and inverter, check the insulation resistance of each part of the cable to the ground, find out the problem, and replace the corresponding cable or connector!
Cause of occurrence:
There are many factors affecting the output power of PV power plants, including the amount of solar radiation, the tilt angle of the solar cell module, dust and shadow obstruction, and the temperature characteristics of the module.
System power is low due to improper system configuration and installation.
Solutions :
(1) Test whether the power of each PV module is sufficient before installation.
(2) The installation place is not well-ventilated, and the heat of the inverter is not spread out in time, or it is exposed to sunlight directly, which causes the inverter temperature to be too high.
(3) Adjust the installation angle and orientation of the PV module.
(4) Check the module for shadows and dust.
(5) Before installing multiple strings, check the open-circuit voltage of each string with a difference of no more than 5V. If the voltage is found to be incorrect, check the wiring and connectors.
(6) When installing, it can be accessed in batches. When accessing each group, record the power of each group, and the difference in power between strings should not be more than 2%.
(7) The inverter has dual MPPT access, each way input power is only 50% of the total power. In principle, each way should be designed and installed with equal power, if only connected to one-way MPPT terminal, the output power will be halved.
(8) Poor contact of the cable connector, the cable is too long, the wire diameter is too thin, there is voltage loss, and finally cause power loss.
(9) Detect whether the voltage is within the voltage range after the components are connected in series, and the efficiency of the system will be reduced if the voltage is too low.
(10) The capacity of the grid-connected AC switch of the PV power plant is too small to meet the inverter output requirements.
Cause of occurrence:
The cause of this fault is a communication problem between the main and secondary CPUs of the inverter control board.
Solution:
(I) Restart the inverter (you need to disconnect the PV.AC grid, and batteries and then turn it on again).
(2) If the problem persists after restarting the inverter, check if the software version of the inverter control board is correct. If not, try to burn in the software again.
(3) If the problem persists after burning the software, replace the control board.
This inverter without an external EPS box, comes with an EPS interface and automatic switching function when needed to achieve module integration and simplify installation and operation.
Cause of occurrence：
(1) The output voltage of the module or string is lower than the minimum working voltage of the inverter.
(2) The input polarity of the string is reversed. The DC input switch is not closed.
(3) The DC input switch is not closed.
(4) One of the connectors in the string is not connected properly.
(5) A component is short-circuited, causing the other strings to fail to work properly.
Solution:
Measure the DC input voltage of the inverter with the DC voltage of the multimeter, when the voltage is normal, the total voltage is the sum of component voltage in each string. If there is no voltage, test whether the DC circuit breaker, terminal block, cable connector, component junction box, etc. are normal in turn. If there are multiple strings, disconnect them separately for individual access testing. If there is no failure of external components or lines, it means that the internal hardware circuit of the inverter is faulty, and you can contact Renac for maintenance.
Cause of occurrence:
Too many modules are connected in series, causing the input voltage on the DC side to exceed the maximum working voltage of the inverter.
Solution:
According to the temperature characteristics of PV modules, the lower the ambient temperature, the higher the output voltage. It is recommended to configurate the string voltage range according to the inverter datasheet. In this voltage range, the inverter efficiency is higher, and the inverter can still maintain the start-up power generation state when the irradiance is low in the morning and evening, and it will not cause the DC voltage to exceed the upper limit of the inverter voltage, which will lead to the alarm and shutdown.
(1) Before servicing, first disconnect the electrical connection between the inverter and the grid, and then disconnect the DC side electrical (connection. It is necessary to wait for at least 5 minutes or more to allow the inverter’s internal high-capacity capacitors and other components to be fully discharged before carrying out the maintenance work.
(2) During the maintenance operation, first, visually check the equipment initially for damage or other hazardous conditions, and pay attention to anti-static during the specific operation, it is best to wear an anti-static hand ring. To pay attention to the warning label on the equipment, pay attention to the inverter surface that is cooled down. At the same time to avoid unnecessary contact between the body and the circuit board.
(3) After the repair is completed, make sure that any faults affecting the safety performance of the inverter have been resolved before turning the inverter on again.
Cause of occurrence:
The voltage and frequency of the AC power grid are out of the normal range.
Solution:
Measure the voltage and frequency of the AC power grid with the relevant gear of the multimeter, if it is really abnormal, wait for the power grid to return to normal. If the grid voltage and frequency are normal, it means that the inverter detection circuit is faulty. When checking, first disconnect the DC input and AC output of the inverter, and let the inverter power off for more than 30min to see if the circuit can recover by itself, if it can recover by itself, you can continue to use it, if it can’t be recovered, you can contact Renac for overhaul or replacement. Other circuits of the inverter, such as the inverter main board circuit, detection circuit, communication circuit, inverter circuit, and other soft faults, can be used to try the above method to see if they can recover by themselves, and then overhaul or replace them if they can not recover by themselves.
We can upgrade the batteries’ firmware remotely, but this function is only available when it works with Renac inverter because it is done through the datalogger and inverter.
If a customer uses a Renac inverter, a USB disk (Max. 32G) can easily upgrade the battery through the USB port on the inverter. Same steps as upgrading the inverter, just different firmware.
RENA1000 series outdoor energy storage cabinet integrates an energy storage battery, PCS, energy management monitoring system, power distribution system, environmental control system, and fire control system. PCS is used to facilitate maintenance and expansion. Pre-maintenance of outdoor cabinets can reduce floor space and maintenance channels. It has the characteristics of safety, reliability, rapid deployment, low cost, high energy efficiency, and intelligent management.
The 3.2V 12oAh cell, 32 cells per battery module, connection mode 16S2P. Battery cell manufacture is from EVE.
Under common application scenarios, the operation strategies of energy storage systems are as follows:
Peak-shaving and valley-filling: when the time-sharing tariff is in the valley section: the energy storage cabinet is automatically charged and standsby when it is full; when the time-sharing tariff is in the peak section: the energy storage cabinet is automatically discharged to realize the arbitrage of tariff difference and improve the economic efficiency of the light storage and charging system.
Combined photovoltaic storage: real-time access to local load power, photovoltaic power generation priority self-generation, surplus power storage; photovoltaic power generation is not enough to provide local load, the priority is to use battery storage power.
Protection level IP55 can meet the requirements of most application environments, with intelligent air conditioning refrigeration to ensure the normal operation of the system.
Remote data monitoring and control from the app in real-time, with the ability to change settings and firmware upgrades remotely, understand pre-alarm messages and faults and keep track of real-time developments.
Intelligent temperature management is changed in battery temperature during system operation, the system will automatically turn on the air conditioning to adjust the temperature according to the temperature to ensure that the whole module is stable within the operating temperature range.
The highly accurate SOX algorithm, using a combination of the ampere-time integration method and the open-circuit method, provides accurate calculation and calibration of the SOC and accurately displays the real-time dynamic battery SOC condition.
Dynamic load balancing is an intelligent control method for EV charging that allows EV charging to run simultaneously with the home load. It provides the highest potential charging power without affecting the grid or household loads. The load balancing system allocates available PV energy to the EV charging system in real-time. As a result, the charging power can be instantaneously limited to meet the energy constraints caused by the consumer’s demand, the allocated charging power may be higher when the energy usage of the same PV system is low on the conversely. In addition, the PV system will prioritize between home loads and chargers.
If rated power charging is ensured then please reference the calculation below.
Charge time = EVs power/charger-rated power
If rated power charging isn’t ensured then you have to check APP monitor charging data about your EVs situation.
This type of EV charger has AC overvoltage, AC undervoltage, AC overcurrent surge protection, grounding protection, Current leakage protection, RCD, etc.
