This document aims to provide users with troubleshooting guidance for common faults on the Renogy 48V 3500W Solar Inverter Charger (SKU: RIV4835CSH1S).

Solar Inverter Problems

Common problems with inverter chargers include:

• Power-on failure
• Cycling start
• No output
• Abnormal AC/PV Charge Function

Below are some helpful troubleshooting steps for different problems.

Power-on Failure

Symptom: The inverter does not power up.

1. If the inverter is only connected to the battery, use a multimeter to measure the voltage on the inverter input terminal. If the voltage is lower than 44V, check the battery specifications and capacity. Disconnect the battery and charge it fully before connecting it to the inverter. If the voltage is 0V, check if the circuit breaker and fuse are normal, and if the wiring between the inverter and battery is correct. If the voltage is normal, and the display screen does not light up when the inverter switch is turned on, please contact us.
2. If the inverter is connected to the solar panel, use a multimeter to measure the voltage on the PV input terminal. The PV input voltage should be between 60V-150V. Overvoltage may damage the inverter.
3. If the inverter is connected to shore power, use a multimeter to measure the voltage on the AC input terminal. Note that reverse connection may damage the inverter. If the voltage is normal, please contact us.

Symptom: After turning on the inverter, the red LED fault light comes on, a buzzing sound is heard, and then it shuts down.

1. Disconnect all loads on the inverter, and measure the battery voltage on the inverter input terminal during the startup process. If the battery voltage is below 40V during this process, please check whether the wire gauge is properly sized. If the wire gauge is undersized, replace with the correct gauge wire.
2. Next, check whether the battery maximum discharge current is higher than the inverter start current. If the maximum battery discharge current is lower than the inverter start current, you need to increase the size and capacity of your battery bank.
3. If the input voltage is above 60V, check the battery voltage level or if there is another charging equipment connected to the battery is also sending a voltage higher than 60V. If so, disconnect the equipment from the battery.
4. Check if the ambient temperature around the inverter is higher than 131ºF. If it is, disconnect the loads and allow the inverter to cool.
5. If the inverter starts and then shuts down, please check the fault code displayed on the screen before shutdown and refer to the manual to troubleshoot the corresponding fault code.

If none of the above steps solves your problem, please contact us.

Cycling Start

Symptom: The inverter is cycling on and off by itself.

Disconnect all loads. If the PV input voltage fluctuates around 60V, it is due to insufficient PV input voltage causing the inverter to cycle on and off. If the PV input voltage is normal, measure the battery voltage on the inverter input during the cycle start process.

1. If the input voltage drops to 0V before shutdown, check if there is a self-resetting fuse or circuit breaker on the input terminal.
2. If the input voltage drops below 40V before shutdown, check the battery level and whether the maximum continuous battery discharge current is greater than the load operating current. Running current = load power / conversion efficiency 90% / 48V.
• If the maximum continuous discharge current is not high enough, you need to increase the number of batteries to ensure normal operation.
• If the maximum continuous discharge current is sufficient, it may be caused by battery decay or low power.
3. If the input voltage is within the normal range during the cycle start process, please contact us.

No Output

Symptom: The inverter is on but has no output
If the inverter can start normally but there is no output, measure the voltage on the output terminal. If the voltage is normal, check the output circuit. If there is no voltage, please contact us.

Insufficient Load Capacity

Symptom: Inverter is on but not able to start or run a plugged in device.

1. Confirm the operating power and startup power of the load. For inductive loads, the startup power may exceed three times the rated power, so it is necessary to ensure that the startup power of the load is less than the peak power of the inverter, and the operating power is less than the rated output power of the inverter.
2. Check if the inverter input wire gauge, fuse, and circuit breaker specifications are too small.
3. When there is no shore power or PV connected, confirm that the battery specifications can output enough current to run the load. Check if the battery voltage and discharge current meet the requirements. Assuming the inverter conversion efficiency is 90%, to run a 3000W load, the continuous discharge current of the battery needs to be 3000W/90%/48V=69.44A. If the battery discharge current is insufficient, the battery voltage will decrease. Turn on the inverter, then turn on the load, and measure the voltage changes on the inverter battery input terminal. If the battery voltage drops below 42V during this process, check if the battery level and discharge current are sufficient. If the battery voltage does not drop below 42V during this process, please contact us.
4. When the battery is connected to shore power and PV, and parameter 01 is set to Utl, the inverter's load depends on the shore power input.
5. If the above steps do not resolve the issue, please contact us.

Charge Function Abnormal

For the RIV4835CSH hybrid inverter charger, it can charge the battery using AC or PV input. If the device is not charging or charging behavior is not as expected, please follow the steps below to troubleshoot:

1. Is there an error code displayed on the screen? Inverter cannot charge the battery when there is a fault, so please check for existing faults first.
2. For PV troubleshooting, see the PV troubleshooting steps.
3. For AC troubleshooting, see the AC troubleshooting steps.

PV Troubleshooting Steps

1. Try to disconnect and reconnect the PV input. The inverter has the following limitations for PV input:

60V ≤ the solar input open circuit voltage ≤ 150V
the solar input wattage ≤ 4400W

2. Check the parameter settings. 

• Parameter 06 selects the battery charging mode, and four modes respectively set the PV and AC charging priorities. When Cub is selected, the battery will not be charged even if PV is connected if AC is present.
• Parameters 07 and 36 respectively set the maximum total charging current and maximum PV charging current. If set to 0A, the charging method is disabled.
• Parameter 08 selects the battery type, and different battery types have different charging parameters that may affect the charging process.

AC Troubleshooting Steps

1. Try to reconnect the AC input and observe whether the AC icon appears on the display.
2. Check the parameter settings.

• When parameter 01 is selected as SOL or SBU, AC will only charge the battery when the battery voltage drops to parameter 04.
• Parameters 04 and 05 can respectively set the AC start charging voltage and AC stop charging voltage when parameter 01 is selected as SOL or SBU.
• Parameter 06 selects the battery charging mode, and four modes respectively set the PV and AC charging priorities. When CSo is selected, AC will only charge the battery when there is no PV. When oSo is selected, AC will not charge the battery.
• Parameters 07 and 28 respectively set the maximum total charging current and maximum AC charging current. Setting to 0A means that the charging method is disabled.
• Parameter 08 selects the battery type, and different battery types have different charging parameters that may affect the charging process.
• Parameter 39 sets the maximum AC input current, which may also affect the charging if the input current is insufficient to power the load.

If the above steps do not solve your problem, please contact us.

Smoke

Symptom: Smoke coming from the inverter

At the first sign of smoke, discontinue use of the product immediately. Disconnect all batteries and wiring. Follow the steps below to check the inverter:

1. Check if the input battery voltage and PV input voltage exceed the inverter limit. If so, replace the battery with a battery with the correct voltage for the inverter. Alternatively, reduce the number of solar panels in series to ensure that the PV voltage is within the allowable range.
2. Check if the wiring to the inverter input or output is reverse-connected or shorted. If it is, correct the wiring per the instruction manual.
3. Check if the inverter output is connected to the same circuit as other power sources. If it is, disconnect the inverter from the circuit. Make sure that only one power source is connected to the circuit.
4. Ensure the N output is NOT bonded externally to the G output of the inverter.

If the above steps do not solve your problem, please contact us.

Output Abnormal

If the output voltage, frequency, etc. are abnormal, please check if the voltage and frequency settings are correct, and then record the abnormal situation with video and contact us.

Internal Abnormal Sound

If there is any abnormal sound or noise during the operation of the inverter, please turn it off, disconnect it, and contact us.