Hi , I’m wondering if someone can help me . I purchased a Allpower 200W flexible solar panel for a pop top caravan and a Victron MPPT 100/20 controller . Before I stick the flexible panel on the roof I thought i would temporary connect up .
On connecting the Victron to blue tooth on the the solar it reads reads 5W ! This is on a cloudy / rainy day but still very low
I’m wondering if I have to set the controller up or if there is a fault with the panel .
I waited till the sun came out and from a tube video tested the panel with a multi meter and it reads 36.5 volts which on the back of the panel the open voltage reads ( VOR) 38.4 v +or- 5%
The short circuit current is 6.5Amps and on the rear of the panel reads 6.87A
I’m wondering what or if I’ve done something wrong or I have to put settings into controller .
This is the screen shot of the wattage I’m not sure if it’s enough info the battery was connected the the caravan electrics as it has a solar connection but I did try straight to battery also , the battery is a lead acid but I’m not sure if I have to select which type of battery it has to be .
To be honest I presumed I just connected the pV to the controler and it would sort its self out and give me a nearer reading to the 200w panel I bought .
I also connected again I. Sunlight and got 25 watts .
I did have the connectors temporary connected as until I’m confident the panel is working ok then I will stick to the roof and connect with the proper solar connectors but did not think that the connections would affect the reading by so much .
My concern is that the controler and PV are compatable really
Does the controller turn down that PV solar reading if it does not need any more power to the battery I’m thinking .
I’m presuming that reading should show the actual wattage the panel is generating all the time but adjusts what it is then sent to the battery if full?
The whole purpose of the controller is to control the output of the panel to match the demand by the battery or load. If the battery is full or your load is small then it will only provide what is needed. In your screenshot the battery voltage is at the float setting of 13.8V, that is the required target and it is being achieved with 5W. All is well, your MPPT is working. If it did not do this then it would overcharge the battery or put too much voltage into your equipment. Because the load/battery is limiting there is no way for the controller to tell you what it could deliver to a larger load or empty battery.
I think I am mis understanding what the Big Solar reading is saying . I thought that it was telling you how much wattage the pV panel was providing .
So you are saying this reading just states the wattage that it is drawing at that present time to keep the battery at full charge ,not the overall amount of power the solar panel is generating at that present time considering the weather conditions.
I’m presuming that to know my Solar panel is working correctly is not looking at the solar read out but the solar voltage and presume it will provide enough wattage?
Are there any basic settings like type of battery etc I need to make In the app to ensure optimum performance of the MPPT controller?
Sorry if I sound a bit confused but I bought this controller as I need a controller to run the PV and this seemed to be recommended, so am not sure what it does completely .
Thank you for your information from your answers I full confident to stick the panel to the roof with some spaces between the adhesive and panel for ventilation and connect more permanently
If the battery is empty and it can take more power than the panel can produce the controller the controller makes sure the panel runs at the maximum power point (MPP) which in this case is about 36V. If the day is cloudy it will produces say 80W but the MPP will still be around 36V. If the battery is full and can only take say 20W, the controller forces the panel voltage up to about 43V so the panel is only producing the 20W. if no power is required it goes right up to 44V at which point the panel can not produce any power. Many people including yourself think that in full sun the panel would produce 180W and somehow waste 160W if the battery only needs 20W. I hope that I have explained that the panel is forced to produce only the power required.
If as in your screenshot the power is low and the PV voltage is around 35V and the controller is at 13.8V or higher all is OK.
Yes, you need to select the correct voltage settings for your battery. Your battery should have recommended voltages for absorption and float and you should program these. The manual provides info, link below to the settings section. If you want further advice, post details of your battery.
The red exclamation mark next to the settings gear (circled in your screenshot) means that the charge controller has an active warning, alarm, or notification that needs attention.
Could be battery settings mismatch (e.g., wrong absorption/float voltages for the battery type) go to settings and check.
Thankyou for that explanation that is a really great way of explaining and understanding how the controller works , that it increases voltage to decrease output . I appreciate your help .
Where do I find info about the battery’s absorbtion/float settings etc to match I the app, as the battery just says 100ah and I know it is a12 v lead acid .when I look at the battery settings in the app It does not give a specific name of lead acid battery ?
I’ll have a read of the instructions you have sent reference too . They are quite in depth with a lot of technical words as it starts talking about a flag that may need moving .
What type of lead acid battery. If you can not find out anything from the battery manufacturers web site then 14.4V absorption and 13.6V float are safe values for many lead acid batteries.
This type of equipment is not consumer electronics and requires knowledge for installation, if you are unsure consult a professional.
Hi , i spent the weekend installing the solar panel and cables and it seems to be working correctly although i did not have direct sunlight . i have checked the battery for info on it (se Pics) but cannot seem to find the manufacture online just suppliers fo any more info . Therefore i have changed the battery type too Gel Victron deep discharge 2, float values too 13.6 V and absorption too 14.4v as you suggested.
Im presming this is all the info i need to put into the battery settings to get optimum protection and performance as there are no red warnings come up in the settings ?
Also i am considering getting an inverter for mains which i presume i can run from the load terminals on the MPPT is that correct and is there a maximum i can run from the 200w panel i have ?
Do not connect an inverter to the load terminals of the MPPT. Inverters have a high start up current that will overload the load output. Connect the inverter to the battery through a fuse. The size of the inverter depends on how much power you need, how long you will run it to give the energy consumption vs the solar energy yield. Also the battery will set the max size, probably around 500-750W. Look at the inverter manuals and they will recommend required battery size.
Hi, thanks for your advice. On not connecting to load terminal . i will look into inverters and info on them i do not need alot of power just charging of electrical appliances .
Can I ask is there information somewhere in the app which shows how much wattage the solar panel is generating at anyone time ?
Hi , thanks for your reply Sorry I’m not sure you are understanding what I’m trying to see in the app
what I’m trying to ascertain from my previous messages .
I have a 200w solar panel and what I want to see is in different weather conditions how much the panel ( also if it is providing the wattage I paid for ) is producing at that present time by looking at the app, so that I know when I’m away it is capable of providing enough power for the electrical devices I am using or wanting it to power . or is this app for this particular controller not able to show that on this particular screen or can I change to another view to view this.
It’s just I have friends who look at their controller app and it shows what the panel is producing ( or capable of producing at that present time)
From your previous messages I understand the MPPT controller is designed to protect and give just enough power to the battery to keep it at its optimum therefore turns down the input power from the panel so what I see on the screen is that power .
The maximum I have seen on the solar screen is 21w which is fine as that’s what it’s designed to do.
I want to make sure during daylight hours when I charge devices ,or use a 12v fridge I have enough power so at night I will then turn everything off so I don’t drain and damage the battery.
I’m not sure what would happen although the solar panel will keep the fridge running all day ,dependant on weather conditions would it just drain the battery at night and damage it if I left it drawing power
