HQST MPPT 40amp Charge controller.

[Richard Reid]

I revive this thread because I have the same problem.
I've come to the conclusion that it's the controller fault. I think it has something to do with the controller itself over heating.
Previously I have the exact HQST 40a. Pretty damn good controller compared to my Renogy 40a.
I have 4 100w in 2s2p. With the HQST, I've hot as high as 407w but mostly in the 320w range.
Runs great, NP except the BT is like shit. I move beyond 10ft and it disconnect. I bought it mainly for the BT.
Returned it and got the BougeRV clone 30a mppt(Sunwhale). The glass face version you see on Amazon. All these are probaly made by the same company. I got the 30a because I'm planning on going 24v so 30a mppt is plenty.
First day, runs great until 1pm,(BT range is good) then I get the error just like you posted.
"Battery voltage has exceeded controller limit.
Check battery bank voltage for compatibility
with controller".
I know there is nothing wrong with my setup as I've rans this for ages with 2 different controllers. Gotta be the controller.
I read in an Amazon review that the controller report a higher temp than actual. Maybe this is the problem.
I'm going run this again tomorrow and see if the same problem arise. It's getting returned regardless.
I will try this next.

https://www.amazon.com/gp/product/B09YRL94D7/ref=ox_sc_saved_image_2?smid=A33R2ILYO7XLEZ&psc=1

If this fail, I might go back to the HQST 40a as that ran flawlessly minus the BT.

I have both 40 and 60 amp hqst charge controllers. They are charging 3 x 24v SOK batteries. My setting are set according to SOK. Both seem to be overcharging my $3900 batteries.

I first had problems with one of the controllers overheating at 20 degree ambient temperatures with only 30amps coming out of a 60 amp controller. The load output on the same controller was not working and kept giving me an overload warning when the draw was only 16 amps (supposed to do 20)

Contacted HQST and 4 months later received a reply asking a bunch of questions that were answered in the original email. I replied back. But its only been 2 months so no answer yet. I guess 2 questions covers the warranty period.

Now.

I have both controller hooked in parallel without the cable so i can see what each controller is doing. Im set with boost at 29.2 and float at 27.6. We had a bit of sun today (i live in the arctic) and my both controller were charging at about 29.5v and when i checked "todays running data" both controllers showed extremely high voltages at 30.7v and 31.4v

I don't know what to do and thats a lot of money to just toss into the garbage.

 

[MisterSandals]

My setting are set according to SOK.

Are these settings a secret?

What is your array?

How are you connecting these SCCs in parallel? Both connected to same batteries or ??

 

[MisterSandals]

In this context, the Mexxsun MPPT 40A 12/24 V Charge Controller (MPJ40) has emerged as one of the most valuable investments for my solar panel system.

You should start a new thread for your new topic. That will allow this thread to address HQST and your thread to proceed as you wish.

 

[Minimoose]

You should start a new thread for your new topic. That will allow this thread to address HQST and your thread to proceed as you wish.

Never seen an mppt with usb ports. Does anyone actually make them?