Hi I have a question regarding volts into a solar charge controller. Currently I have a 40 amp EPEVER solar charge controller. It states that the max PV open circuit voltage is 100VDC. Right now I am using RICH SOLARS 100 watt panels. I have 4 of them and would like to go to 5. I would be hooking them up in series. The only problem/concern I have is that the solar panels are rated at open-circuit voltage of 22.6. So with all 5 of them together I would have a total of 113 volts. My question is if this is going to be detrimental to the solar charge controller? Do I have any other option? The solar charge controller is rated to accept 550 watt. I have a 12 volt system.
To many volts in solar charge controller ok?
- Thread starter Mjr
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chrisski
Solar Boondocker
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Do not exceed the voltage. With 4 panels look at the record cold temperature for the area you can operate at and then figure out the temp coefficient. With four panels that may push too much voltage.
Also, even though the open circuit voltage is higher than the operating voltage, whenI see the sun just start to come out, my voltage starts higher with next to no amps and drops as amps start to rise. So I use th ripen circuit voltage.
If the controller is a MPPT controller, you may be able to go 3S2P.
In general, you’re supposed to be able to exceed amps forcharge controllers, but exceeding voltage is bad ju-ju and can ruin them. I’ve never put that to the test for any of my solar charge controllers Since I paid money for them.
Also, even though the open circuit voltage is higher than the operating voltage, whenI see the sun just start to come out, my voltage starts higher with next to no amps and drops as amps start to rise. So I use th ripen circuit voltage.
If the controller is a MPPT controller, you may be able to go 3S2P.
In general, you’re supposed to be able to exceed amps forcharge controllers, but exceeding voltage is bad ju-ju and can ruin them. I’ve never put that to the test for any of my solar charge controllers Since I paid money for them.
This won't work since the OP stated the SCC max is 550W. 3S2P with 100W panels is of course 600W.
chrisski
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I agree if the max input specs are 550 watts or it’s not stated. THe exception I’m trying to say is some manuals say a 50 amp charge controller can have up to 60 amps of panels attached. My Victron 100/50 says that. Intent of that is since those panels will not see greater than 50 amps much, the output will be clipped To the max wattage of 720 wats for a 12 volt battery or 1440 watts for a 24 volt battery.
Bud Martin
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If you look at the EPVER user manual, the max Panel power is 1.5 times the rated charging power of controller.l.
You will not get the Wattage from panel in the real world any way.
Read page 8:
2) Maximum PV array power The MPPT controller has the function of current/power-limiting, that is, during
charging process, when the charging current or power exceeds the rated charging current or power, the controller will automatically limit the charging current or power
the rated charging current or power, which can effectively protect the charging parts
controller, and prevent damages to the controller due to the connection of
over-specification PV modules. The actual operation of PV array is as follows:
Page 9:
According to “Peak Sun Hours diagram”, if the power of PV array exceeds the rated charging power of controller, then the charging time as per the rated power will be prolonged, so that more energy can be obtained for charging the battery. However, in the practical application, the maximum power of PV array shall be not greater than 1.5 x the rated charging power of controller. If the maximum power of PV array exceeds the rated charging power of controller too much, it will not only cause the waste of PV modules, but also increase the open-circuit voltage of PV array due to the influence of environmental temperature, which may make the probability of damage to the controller rise. Therefore, it is very important to configure the system reasonably. For the recommended maximum power of PV array for this controller, please refer to the table below:
You will not get the Wattage from panel in the real world any way.
Read page 8:
2) Maximum PV array power The MPPT controller has the function of current/power-limiting, that is, during
charging process, when the charging current or power exceeds the rated charging current or power, the controller will automatically limit the charging current or power
the rated charging current or power, which can effectively protect the charging parts
controller, and prevent damages to the controller due to the connection of
over-specification PV modules. The actual operation of PV array is as follows:
Page 9:
According to “Peak Sun Hours diagram”, if the power of PV array exceeds the rated charging power of controller, then the charging time as per the rated power will be prolonged, so that more energy can be obtained for charging the battery. However, in the practical application, the maximum power of PV array shall be not greater than 1.5 x the rated charging power of controller. If the maximum power of PV array exceeds the rated charging power of controller too much, it will not only cause the waste of PV modules, but also increase the open-circuit voltage of PV array due to the influence of environmental temperature, which may make the probability of damage to the controller rise. Therefore, it is very important to configure the system reasonably. For the recommended maximum power of PV array for this controller, please refer to the table below:
Watts is kind of a fuzzy number for a solar charge controller. We can over panel and exceed the wattage spec. Not a problem.
Volts is not a fuzzy number. It is a hard number. Very hard. Exceeding the volts has the potential to cause the solar charge controller to fail, depending on the quality of the controller.
Volts is not a fuzzy number. It is a hard number. Very hard. Exceeding the volts has the potential to cause the solar charge controller to fail, depending on the quality of the controller.
