HQST charge controller

[cotton top]

I have an HQST 40 amp charge controller for a 24 volt battery setup. Batteries are two 12 volt in series. My solar panels are 600 watts. I'm getting an E10 error code which means that the solar panel input is too high. I'm not sure how to correct this.

 

[wme]

Try 1 panel to verify functionality of your system

 

[Rednecktek]

The 20, 30, and 40 amp HQST's have a VOC limit of 100v. If you've got 600w of panels in series you're probably over that.

Panel specs?

 

[cotton top]

​

 

[wme]

Thinking that a 3s 2p set up would be very usable.

 

[cotton top]

Thinking that a 3s 2p set up would be very usable.

I'm so new to solar I have no idea what that means.

 

[cotton top]

The 20, 30, and 40 amp HQST's have a VOC limit of 100v. If you've got 600w of panels in series you're probably over that.

Panel specs?

100 Watt 9BB Solar Panel​

• Max Power at STC: 100W
• Open Circuit Voltage: 24.3V
• Short Circuit Current: 5.21 A
• Optimum Operating Voltage (Vmp): 20.4V
• Optimum Operating Current (Imp): 4.91A
• Maximum System Voltage: 600 VDC UL

There are six of these panels

 

[Rednecktek]

Yup, there's your problem. I'm guessing all 6 of those panels are connected to each other? That's almost 150v into a 100v controller.

I'm so new to solar I have no idea what that means.

So connect 3 together to each other (that's 3 series, or 3s) and do it again for the other 3.
Then take those 2 sets of 3 and connect them to a Y splitter which puts the 2 sets in parallel (2p).

That'll get you 3s2p and your voltage will be down to about 75v (makes the controller happy) and 10.4a which is still manageable wire size.

 

[MisterSandals]

connect them to a Y splitter

https://www.amazon.com/BougeRV-Connectors-Branch-Parallel-Adapter/dp/B0753X68PS/

 

[MisterSandals]

That'll get you 3s2p

Diagram:

3s2p

Can someone help me with a diagram of 3s2p for solar panels. All panels are 100w My set up is 12v system. Renogy Rover Li 40a CC. 1,000w pure sine wave inverter. Three 120 ah LifePO4 batteries wired in parallel.

diysolarforum.com

 

[cotton top]

Yup, there's your problem. I'm guessing all 6 of those panels are connected to each other? That's almost 150v into a 100v controller.


So connect 3 together to each other (that's 3 series, or 3s) and do it again for the other 3.
Then take those 2 sets of 3 and connect them to a Y splitter which puts the 2 sets in parallel (2p).

That'll get you 3s2p and your voltage will be down to about 75v (makes the controller happy) and 10.4a which is still manageable wire size.

 

[cotton top]

Yup, there's your problem. I'm guessing all 6 of those panels are connected to each other? That's almost 150v into a 100v controller.


So connect 3 together to each other (that's 3 series, or 3s) and do it again for the other 3.
Then take those 2 sets of 3 and connect them to a Y splitter which puts the 2 sets in parallel (2p).

That'll get you 3s2p and your voltage will be down to about 75v (makes the controller happy) and 10.4a which is still manageable wire size.

Thank you!!

 

[MisterSandals]

I'm getting an E10 error code which means that the solar panel input is too high. I'm not sure how to correct this.

That's almost 150v into a 100v controller.

Violating input voltage at all, let alone by 50% (50V!) usually lets the magic smoke out and the SCC would be a goner.

Good engineering if this was designed to protect itself from such an egregious voltage.

Good luck! Keep us posted how this turns out and don't be surprised if your HQST is dead.

 

[Minimoose]

I have an HQST 40 amp charge controller for a 24 volt battery setup. Batteries are two 12 volt in series. My solar panels are 600 watts. I'm getting an E10 error code which means that the solar panel input is too high. I'm not sure how to correct this.

You're good for 100 volts on the 40 amp HQST. I've gotten pretty close, but never went above. Take your open circuit voltage and add about 3° per panel for colder weather. You must be going over voltage.

 

[Minimoose]

100 Watt 9BB Solar Panel​

• Max Power at STC: 100W
• Open Circuit Voltage: 24.3V
• Short Circuit Current: 5.21 A
• Optimum Operating Voltage (Vmp): 20.4V
• Optimum Operating Current (Imp): 4.91A
• Maximum System Voltage: 600 VDC UL

There are six of these panels

Mine are the same panels. I can get away with 4 in series in the hot weather, but they throw an over voltage code in the cold weather. 3s/2p will fix your problem.

 

[chilly2]

Violating input voltage at all, let alone by 50% (50V!) usually lets the magic smoke out and the SCC would be a goner.

Good engineering if this was designed to protect itself from such an egregious voltage.

Good luck! Keep us posted how this turns out and don't be surprised if your HQST is dead.

They're solid. I have the 60A with 150V max and my 120V array went over on one of those perfect cold days recently. The CC E10'd me until I sorted it out. 90V array now. It's much happier and so am I.

@cotton top did reconfiguring your array solve the E10 for you? What config did you settle for?