7210A-MPPT charge controller / step up only
 

First on the list wishing all a peaceful love filled day !

Next is this MPPT labeled controller that can be found for a suspiciously low price of $40 to $50.

Its marketed as a Solar lithium battery charger that will only step up the voltage as its designed to charge high capacity lithium battery packs.


It has a know bug when clouds first pass over it will stop charging for 10 - 15 seconds

Have a plan to test its input / output watt levels with a sine wave multi meter

Has anyone tested this against a actual mppt controller panel efficiency ?

https://ae01.alicdn.com/kf/HTB1xD4xS...pg_640x640.jpg

Description

Intuitive user interface via simple LCD display for visualizing the main MPPT parameters: Charging current, Voltage, Power, Charge time.
Reverse protection circuitry.
Built-in 20 multi-purpose data groups: Set, Store, etc.
Different Working Modes: DC/DC – Boost; MPPT and DC/DC selectable; MPPT for main PV application usage.
Charging Options: Lead-acid- Accumulators; LiFePo4 packs; Li-Ion packs; Li-Poly packs.
100W-600W is the optimal solar PV panel.
Maximal Output Power: 600W
The controller has the automatically cut-off overload protection


Display :

TFT LCD 160 x 128 pixels

System Input Voltage Range[V]:

DC 12-60V

System Output Voltage Range[V]:

DC 15-90V, Adjustable

Output Current Range [A]:

0-10A Adjustable

Output Power Range [P]:

20-600W

Cooling type:

Passive with Heatsink
Active with Fan

Working Modes:

MPPT,
DC-DC out

Item Size: 5.2 x 3.8 x 2.2 inches

Weight: 384 g / 13.56 oz

Here's the manuals translation in proper English

Ming He MPT-7210A Manual Re-translation
Ming He MPT-7210A Specifications
Input Voltage: DC 12V ~ DC 60V
Output Voltage: DC 15V ~ DC 90V, can be adjusted to match the voltage requirement of 24V / 36V / 48V / 72V battery packs
Output Current: 0A ~ 10A
Output Power: 600W Maximum, optimal condition of 100W ~ 600W solar panels

Input Power*: 20W ~ 600W, 12 ~ 60V solar panels, or can be connected to battery packs, lithium battery packs, distributed household solar power systems, electric cars, wind turbines and solar street lamps
(*: I honestly don't know what "Scope" means in this case)

Properties: MPPT technology, automatic battery charge level adjustment, optimal for charging various kinds of battery packs, including lithium battery packs

Display: Color LCD, displays voltage, current, power (in kilowatts or amp-hours), and charge status

Mode: MPPT / DC-DC, MPPT can be used to charge batteries from solar panels while DC-DC mode can be used to step up or down voltage and current in power applications

Charging options: Charge mode can be set according to your needs, maximum of 20 presets can be stored inside the unit

Wiring
WARNING: Please do not mix up solar battery / input and battery / output, or swap positive and negative lines! Unit might explode or catch fire, resulting in property damage and/or loss of life.

1) Plug in solar panel to the top connector, note the polarity. Reverse polarity protection is not implemented!

2) Then, connect the battery wires, like what you did in the previous step. If solar panel connection has power, the display will turn on. If it doesn't, check the connection. Please note that solar panel should be placed outdoors where sun shines onto the panel!

Dimensions of the unit
Size of the unit: 103.5mm x 96mm x 55mm
Mounting bracket: 13.5mm x 67mm, hole spacing is 43mm apart
The two mounting holes are 117mm apart
The unit weighs 400g.

Please install the unit at -10 ~ 60 degrees Celsius, in a dry place.
LCD display can be easily damaged by shock or water infiltration. In order to prevent this, secure the unit to the wall or post firmly. Avoid areas with lots of impact or vibration, as it may cause the irreparable unit damage.
Avoid direct sunlight and rain.


Controls
SET: Set data
UP: Increase value - Hold to enter brightness adjustment menu
DOWN: Decrease value - Hold to calibrate the current measurement to 0
OK: Confirm changes / Turn on or off output - Hold to lock and unlock controls

Display
Setup mode
(Solar panel illustration): Solar panel voltage settings (maximum/optimal voltage?)
(Battery illustration)
(V part): Maximum battery changing voltage
(A part): Maximum charging current
(Box with X): Screen time-out timer
(AH / WH): Battery capacity setting
(000:00:00 part): Charge timer
(Floppy disk with arrow pointing outward): Load preset Number (n)
(OFF): Output status
(Padlock): Control lock status

Normal mode
(Solar panel illustration): Current solar panel input
(Battery illustration)
(V part): Current battery charging voltage
(A part): Current output current
(W): Current charging power in watts
(AH / WH): Cumulative charge capacity
(000:00:00 part): Cumulative charge time
(CV part / OK): Current charge status, OK means fully charged
(OFF): Output status
(Padlock): Control lock status

This guy has been using 3 of them for a year or more, this video and others in his series discuss them at some length. He's reasonably happy overall I think, the conclusion seems to be they work very well in good sunshine but efficiency at lower light levels isn't great.
https://www.youtube.com/watch?v=IpxRg21GQAo

This video helps fill in blanks from the first but its still vague at best.

I guesstimate his PV size is 1200 watts , he said the chargers peaked at 450w - 500w on occasion.

https://www.youtube.com/watch?v=6OdFMB9K2tA

It appears this Monkey is charging 10KW with 3 of these chargers


When it gets here will test it with a Sine wave multimeter

:)

Is there something in particular you're wondering about? That guy is pretty responsive to any questions in his video comments.

My question was has anyone tested this units efficiency against a know mppt charger efficiency.
I would of liked to compare its output to a larger traditional mppt to see what its doing or not doing

He has done some good testing of them @ 80v I will be using it in remote locations to charge 48v ebike batteries to 54v from two 100w 18v panels.

https://www.youtube.com/watch?v=C3lUd0xk1W4

Given how cheap they are I'd probably just give it a go, he will have different input and output voltages so his efficiency will differ from yours also.
The best option of all if you wanted to spend more would be to pick up a Sunpower 300/327W panel, those have an MPP voltage of 54V, a very basic controller would suffice.

I like the sounds of the 54v panel but for my situation the lightweight semi flex panels with the sunpower cells are suited.

They are rated at 17.7v and will be wired in series

What makes them suitable for my use is they are just 3 mm thick salt water spray safe and durable enough you can walk on them , they bend 30 degrees and weigh 3.5 lbs 42" x 21" wide.

Bonus is they are 22% efficient



I have done some number crunching to see how the charge will compare to Mikes charge ratio

Mikes 1500w pv's to 10,000 wh battery = 1 to 6.6

My ratio with 200 watt PV into 750 wh in battery = 1 to 3.75

So I have close to twice the panel size ratio :)

In the future I will likely get two more semi flex panels as they pack together so well its of little inconvenience.

Sounds good, i'm sure the controller will work well for you an it will be interesting to see what the efficiency is like.
Those high quality flexible panels are lovely but they're a little too expensive for me still. Full sized panels are such a commodity item nowadays it's easy to find great deals on them from time to time. It's just a lot earlier in the life cycle of the flexible panels.

When the apparent mppt charger gets here I will also Time the sunlight to cloud transition glitch it has , it might cause a substantial energy loss or maybe not.


The Plot thickens

The panels will be carried set in a Vee in this single wheel trailer and towed behind the ebike. Any charge along the way is a bonus plan is to stop between 11 and 3 to recharge on the road . I will be able to charge once I reach my destination for camping or gold prospecting. Something i do now.

That arrangement is the best way i can carry them if i was to carry them stacked and flat they stick over the side rails 2 inches on either side and risk getting damaged.

https://lh3.googleusercontent.com/Gf...Ckyt7-=s978-no

They are propped up while I design a light angled aluminum frame. Planning to use 1 x 1" x 1/8th inch 6061 angle . It weighs in at 2.16 lbs per 8 ft length and should be strong enough for the job. Home hardware sells it for $22 per 8 ft.

Your image isn't displaying for me unfortunately.

I will try again

Poof

https://lh3.googleusercontent.com/A8...ckRUFQ=s978-no


Rather then a aluminum frame I will be folding a sheet of coroplasts into a pup tent shape and rivet together using washers as backing along seams.
It will have a added fairing at the front end for wind protection and improved Aero

Once its in shape and riveted will spray canned foam along the inside seams for a hidden light weight framework..
It will be removable as a unit from the trailer. The plan is to stop and charge under the mid day sun

A labor of love something Im putting together for spring and summer camping when out Sunning and gold prospecting in the nice weather.


keeping weight down is paramount. The panels weigh 3.5 lbs each

Looks good and shouldn't be too draggy in use.
It might be good to have the option to carry them flat in the event of strong cross winds on your journey?
Any further details on the panels in terms of pricing and source?

I picked them up on eBay.ca listed for $165 OBO with free ship from Canadian warehouse.
Not sure if he ships to the U.S. If your in the U.S with the exchange rate I bet you could find the same panels on eBay.com for around $120

With a good design a convertible type rack could be made up to work like your suggesting I dont have that design but do like the feature.

The design would have to compete with the one peace folded designs riveted seams and no moving parts , no wiggle. Its a tough one to beat. For sturdiness and lightness its about perfect. I will be using the weather forecast for Sun and wind if caught unexpectedly can pull over for shelter from any wind storms etc.

I'd definitely look at making it fold up, if nothing else it would make it a lot more compact for storage when not in use.
That's an excellent price for high efficiency thin panels.

Your idea is good its just not going to mix with my needs.

I have put some thought into designs and decided on a light rigid rack. No moving parts to fail no bending and unbending nothing the one piece design means stability something a fold up rack will not have. In short the losses are too great for a odd wind storm I won't and don't want to ride in. Instead I would pull over , bicycling in wind storms is not productive at all ..I would pull over for shelter regardless of the panels position.

The first design I had was complex to no end. It was flat ( the best) for wind resistance but the panels stuck over the trailer rails 2 inches per side so if the trailer tipped over the panels edge hits first

So its tent style

Sounds like you have the best design for your needs. Will you have some storage underneath also?
The only things putting me off the thin panels is the apparently short life and the fact that the premium sellers claim that the cheaper ones are all made using rejected cells.
I think it makes sense to protect against bending and impact as much as possible as you are.

There is a good chance the most affordable panels may be customer returns for damage then resold at a reduced rate. They also have A b and C grades from the factory.

One panel was without damage the other had 2 pieces of wire sealed under the protective plastic but the panel is fine as the static pressure was low.

You can find semi flex pv with a 20 year manufacturers output warranty so with their life expectancy and my sporadic use I don't think I will be wearing them out.
They only make fiscal sense if you need weight savings durability or the ability to mount on curved surfaces.

This rack design will have about zero failure points
It will have coroplast inner boxed framework joined and filled with canned foam for strength , the rack will have to endure rough roads and be fully removable with panels on board.

The mppt chargers arrived , two of them one for Solar charging and one for a boost converter to increase battery voltage for more speed. Now Im waiting for pv cables to join it up. :)

I forgot to mention the batteries will go on the bottom back of the trailer and supplies in front of them and lighter objects at the very front. I will limit the weight to 40lbs gear including the panels weight.
The trailer weighs 13 lbs on its own for about a 50 lb tow load. The trailer is rated to carry 70 lbs.

Also the trailer is made of welded 4130 Chromoly tube with gussets welded in.

So Im making the rack durable for a good match , the flat version was going to use Chromoly tube...


I just thought about it now but will use them at home when not doing distance on the ebike
It makes fiscal sense ..

The below reflector method works to boost panel output. So will lay out some Tyvek at base of the panels when at the home as well bike trips.

http://geo-dome.co.uk/cumbria/Photos/Solar.jpg

Mikes Garage rooftop panel set up

https://www.youtube.com/watch?v=oEt4xJVm3uQ

Has anyone here used NIMH batteries for solar storage?
I am thinking of trying to use them, instead of Lead acid or Lithium.
If someone has used them, any info as pro and con or setup would be appreciated.
I have 3 100 watt panels and will have approx 1.6KwH of NIMH.
25p10s at 5.5Ah per 10s at 12v nominal. 5.5 x 25 x 12 = 1650 if my math is right.
I am planning on using an arduino to make my own solar controller.

Crikey, you waited 9 years to make your first post :)
No reason NiMh shouldn't work fine once you use the correct charging algorithm, the only downside might be the self discharge but I don't think that will be a major obstacle for you.

Sorry if posted already, I only skimmed the three pages. Niall of Raglan Electric Bikes here in NZ has done exactly what you want to do :) https://www.youtube.com/watch?v=FRW5PdDkhP0 and https://www.facebook.com/RaglanElectric/

Back to the actual charge controller though. I have one and used a 24v wall wart plug to the input to top off a 48v Chevy Volt lithium module with it. I love the fact that you can set charge points and it will limit the current flow once reached.