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Author Topic: MPPT Solar Charge Controller, best for RFI ?  (Read 29703 times)

K5LXP

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RE: MPPT Solar Charge Controller, best for RFI ?
« Reply #15 on: July 26, 2018, 07:26:23 AM »


I use powerpoles for all my DC connectors, so it's a simple matter to connect one or more panels and one or more batteries to a hub or strip, and it's off and running.  Years ago I used a simple expanded voltmeter in a box to monitor the bank voltage which works fine.  The past number of years I use an inexpensive watthour meter with powerpoles in/out, which can tell you how many watt hours your panels provide or load uses.  Also in the kit are a couple harbor freight freebie DMM's with banana to PP jumpers for insertion inline to monitor voltage or current elsewhere if desired.  Putting an ammeter inline right at the panels can help to orient them for maximum power.  It's a fair statement to say that without a charge controller there's a potential to overcharge the batteries, but it's assumed you set all this stuff up to run something, so that normally isn't an issue.  If there's a situation where the solar system is set up before the load, just shade or disconnect the panels.  Or, if you have so much charging capacity that the load doesn't keep things in check, just disconnect one or more panels, or tilt them away from the sun.  How much panel and battery capacity you need depends a lot on your load, run time and duty cycle.  It works out that your window of decent panel output is relatively short - just a few hours around solar noon.  So if you use your load any appreciable amount before and after that, your battery capacity comes more into play.  Throw some clouds in there once in a while and watch things go into deficit mode in a hurry.

Nothing will replace hooking stuff up and experimenting in your specific use cases.  That's how I've ended up with half a dozen different panels and a selection of different capacity batteries, along with a go bag full of powerpole jumpers and adapters.  I can dynamically assemble a system that's balanced, heavy on solar, or heavy on battery, and sized for whatever loads I anticipate using.

Mark K5LXP
Albuquerque, NM
   
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N8AUC

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RE: MPPT Solar Charge Controller, best for RFI ?
« Reply #16 on: July 27, 2018, 05:25:15 PM »

Yeah, my understanding was that the main purpose of the charge controller was to
regulate the panel output, and prevent overcharging the batteries. But the way you
have everything metered up, it's basically you who is acting as the charge controller.
Which is totally cool, just as long as you aren't cooking your batteries.

Still, I'm a huge fan of metering everything so you can see system status at a glance.
Which is why I built all those meters into my battery box.

On my "to do" list, is to build a meter box (analog voltage and current) to sit between
the panels and the charge controller, so I can see exactly what the panels are
putting out. I already cut the supplied cable and inserted power poles, at the point
where I intend to insert the meter box.

It's been a lot of fun playing with it so far.

73 de N8AUC
Eric
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K5LXP

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RE: MPPT Solar Charge Controller, best for RFI ?
« Reply #17 on: July 28, 2018, 06:58:42 AM »


You're right, the operator becomes the charge controller.

This is what I use for system monitoring.  There are lots of units like this out there and they're not expensive.  You can see everything you need to know at a glace and it's always counting Ah as long as it's powered.



Speaking strictly of portable/temporary solar, the way I look at it is if you have so much extra panel that you need to regulate it, your system is imbalanced.  Given that there are only so many charging hours in the day and your battery is carrying the load the rest of the time, your panels are usually in catch-up mode.  In my experience, it's a rare occasion your battery is 100% and you need to shut down panels.  Maybe if you start Field Day with a fully charged battery at noon, your panels won't have much to do except run the load.  But the next morning after the battery has been discharged for maybe 18 hours, the panels will be fully loaded for likely the rest of the day and still may not fully charge the battery.  You could just run a charge controller anyway, it can't hurt.  If it's an EMI-free one then sure.  But I will bet as you go, the issue will be insufficient charge and finding ways to shed loads than shading panels.  If you want to design a system that has so much charge overhead it will bring your batteries up from dead to full in one cycle no matter what, then you can do that.  You can also design a system that has enough battery to ride through hours or days of clouds.  But you pay for that in panels, batteries, transporting everything and setup.  The trick is striking the balance between size, cost, and anticipated use.  And as you observe, it's a fun challenge to set up a system and see how close you get to your goal, and what if any issues come up that give you a different result.  That's why I like having a selection of panels and different capacity batteries.  I can plug and play a solar solution together based on the anticipated use or compensate for unforeseen circumstances.  I can also make more than one system if I have multiple load locations.  Or I can combine all the panels and batteries as one system and run a whole campsite.   While usually the most practical answer is to just plug into the car (since all those panels and batteries have to get there somehow...) there is some satisfaction in deploying a system you designed that's providing power silently.

Mark K5LXP
Albuquerque, NM
 
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KD8SKM

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RE: MPPT Solar Charge Controller, best for RFI ?
« Reply #18 on: August 28, 2018, 03:51:23 AM »

The key to Solar Power is getting every available watt of power out of the panel

PWM controllers such as the Harbor Freight one are RF quiet because they switch at less than 10 Hz.... However they do not do power conversion and NEVER will operate at the Panels Maximum Power Point.  You are lucky to get 70% of the panel's power and in many cases far less than that.

It is also true that may MPPT controllers out there are very RF Noisy - Ours is not!

Many Ham's across the globe are using our Apollo Charge controller without RF Issues and it converts power at over 98.5% Efficiency.  True MPPT to get every last watt.

It can be found here:
http://www.diysolarforu.com

It also allows a smaller panel to do the same amount of work - a single 100 Watt panel with our controller can run a 100 Watt rig all day even in partly sunny conditions while charging the battery thanks to the MPPT operation.

Cheers,

Rob
KD8SKM
DIY Solar for U

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LYFAN

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RE: MPPT Solar Charge Controller, best for RFI ?
« Reply #19 on: February 15, 2019, 10:48:50 PM »

Mark-
 MPPT has a couple of extra advantages in certain conditions.
First, because it is PWM instead of pure DC, it creates less boiling, less microbubbles, at the plates. That allows for lower internal resistance and higher charge efficiency, so the batteries will charge faster (faster than they would with pure DC) and less gas will be generated.
 Second, because MPPT can typically work with a wider voltage range, it can and will harvest power from the solar panels when a conventional controller would not. For instance, dawn to 9am and 4pm to dusk, when panel output may be too low for a conventional controller to harvest anything. (This depends on getting an MPPT controller, and setting up your panels to overlap in the voltage range of course.)
 Third, MPPT can pull the same trick--harvesting power from reduced voltage when a panel is partially shadowed and voltage is dropped. These low-power harvests work best when the panels are in series, so the combined voltage is higher but still within the MPPT's range if the panels do get full lighting.
 Yes, RFI can be an issue. But if the sun if playing hide and seek or the rain is predicted to start at noon, knowing that the MPPT controller may be charging your batteries 15-25% faster than anything else, means you'll get that much more charge when conditions are dicey and you need to grab all you can get.
 Some are noisy as seventeen year locusts. Others play nice. If the seller doesn't know what they've got and there's no free return, pick another brand, with a known reputation.
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KD8SKM

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RE: MPPT Solar Charge Controller, best for RFI ?
« Reply #20 on: March 06, 2019, 08:55:15 AM »

We now have released Sol - our 18 amp Buck Boost Charge Controller.

Works even better than the Apollo because it can also boost panel voltage to battery.
Gains are made in low light and partially shaded panels due to the extended 10 to 54 volt operating range.

Now a single 36 cell panel can operate with 12 and 24 volt systems.

Check it out here:
https://www.diysolarforu.com/store/p11/Solar_Charge_Controller_Buck_Boost.html

Cheers

Rob
KD8SKM
DIY Solar for U

We will be at Hamvention 2019 - Flea Market 9007, 9008
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W9IQ

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RE: MPPT Solar Charge Controller, best for RFI ?
« Reply #21 on: March 06, 2019, 09:01:04 AM »

Rob,

It is great to see a company responsive to the needs of the amateur radio market. Keep up the good work.

- Glenn W9IQ
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- Glenn W9IQ

God runs electromagnetics on Monday, Wednesday and Friday by the wave theory and the devil runs it on Tuesday, Thursday and Saturday by the Quantum theory.

KD8SKM

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RE: MPPT Solar Charge Controller, best for RFI ?
« Reply #22 on: March 06, 2019, 01:17:09 PM »

 :) :) :)

Its not just for us Ham's.... anyone that wants to do solar power the right way... on a small or large scale.

There is more in development - stay tuned.

Rob
KD8SKM
DIY Solar for U
https://www.diysolarforu.com

Hamvention 2019 in the Flea Market 9007,9008
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KB1GMX

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RE: MPPT Solar Charge Controller, best for RFI ?
« Reply #23 on: March 25, 2019, 02:09:33 PM »

For field work I use one of to controller both PWM not MPPT.  PWM is quiet and does the job
though MPPT is more efficient.

For typical panels with maximum power point is 17-18V and the charging load is 14 so that means about
10-15% less power for charging so MPPT helps (if its quiet).  If you have excess solar power then the loss
is not a problem.  For cases where the panel is small or less than full sun or marginal sized battery size
then you want every watt you can get.

Typical FD setup is three 20W and a 50W panel plus two Morningstar Sunguard module (80W max PWM)
the three 20W panels have one and the 50 W panel has the other and that runs to the battery and plays
well.  The idea is that the sunsaver cubes are limited to 4.5A max so I split the load and it helps with
sun shading of panels as I can spread them out.  FYI the Sunguard controllers are cheap typically
under 30$ each.  That puts the available solar at the minimum edge for 100W station but it works
for my Tentec radio that uses less DC on RX than many.

No matter what you want more solar power than average TX+ RX power to maintain battery charge
if the operation must make it into the night assuming large enough battery (60 -100ah).

Allison

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K5LXP

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RE: MPPT Solar Charge Controller, best for RFI ?
« Reply #24 on: March 26, 2019, 05:31:03 PM »

There is more in development - stay tuned.

Would love to see a basic solar controller with a basic battery monitor included.  There are lots of fancy smart solar controllers out there, and lots of expensive complicated battery monitors.  I don't care about utmost efficiency or accuracy, I just want basic panel and battery status for my RV a step up from the 4-LED empty/full indicator.  I use cheep chinese battery indicators but the setpoints aren't user adjustable so you have to be an EE to interpret voltages and currents.  Seems even a minimally capable solar controller could report basic battery bank parameters but I haven't found one.

Mark K5LXP
Albuquerque, NM
 
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KD8SKM

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RE: MPPT Solar Charge Controller, best for RFI ?
« Reply #25 on: July 25, 2019, 12:47:10 PM »

Mark:

All of our controllers include an LCD display to tell you the system status including a rough indication of battery state of charge.  Panel voltage, Battery Voltage, Charging Amps, Charging Power, Amp Hours are among displayed items.

you can check out our offering here:

https://www.diysolarforu.com

Our flagship Buck Boost controller is now 20 amps and can be found here:
https://www.diysolarforu.com/store/p11/Solar_Charge_Controller_Buck_Boost.html

It has the highest power conversion performance in the industry at over 99% AND low RFI.  Operates where other controllers will not....

Check them out.

Cheers,

Rob
KD8SKM
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N8AUC

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RE: MPPT Solar Charge Controller, best for RFI ?
« Reply #26 on: July 25, 2019, 06:08:45 PM »

There is more in development - stay tuned.

Would love to see a basic solar controller with a basic battery monitor included.  There are lots of fancy smart solar controllers out there, and lots of expensive complicated battery monitors.  I don't care about utmost efficiency or accuracy, I just want basic panel and battery status for my RV a step up from the 4-LED empty/full indicator.  I use cheep chinese battery indicators but the setpoints aren't user adjustable so you have to be an EE to interpret voltages and currents.  Seems even a minimally capable solar controller could report basic battery bank parameters but I haven't found one.

Mark K5LXP
Albuquerque, NM
 

Mark,
I agree it's hard to find a charge controller that reports battery bank parameters.
You might consider adding a Thornwave Bluetooth enabled current shunt to your battery bank.
It reports all kinds of parameters related to the current state of your battery via Bluetooth to
your smartphone via an app that lives on your phone. The app also works on a tablet that has
Bluetooth, either Android or IOS.

I am looking at putting one of these in my battery box, pending availability of funds.

You can find it at https://amzn.to/2ElUhkH

73 de N8AUC
Eric
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K7KLA

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RE: MPPT Solar Charge Controller, best for RFI ?
« Reply #27 on: August 27, 2019, 03:02:27 PM »

Here is a video of an MPPT Charge Controller that I installed at a Solar Powered Repeater site. It was producing so much interference I had to send it back and exchange it for a PWM.

https://youtu.be/0fwQ9aawZGU
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K7AAT

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RE: MPPT Solar Charge Controller, best for RFI ?
« Reply #28 on: August 28, 2019, 05:46:59 PM »

You want a low RFI solar charge controller?

https://www.diysolarforu.com/products.html

Designed and manufactured in America by an electrical engineer and ham.

Have several in our area and they replaced all the noisy charge controllers we previously had.  Measurements demonstrate they work....no RFI !

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KD8SKM

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RE: MPPT Solar Charge Controller, best for RFI ?
« Reply #29 on: October 11, 2019, 06:10:15 PM »

For those thinking of solar and may be on the fence Herat is a little incentive for my fellow HAM’s:

Use “EHAM19” at checkout for 20% off a Sol or Apollo charge controller.

DiySolarforu.com

Cheers,

Rob
KD8SKM
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