Solar charge controller question

[psytechguy]

As I understand it, an MPPT controller will allow you to use higher voltage solar panels and still charge a 12 volt system. Do PWM controllers offer the same flexibility?

My power needs are small, fans, lights, and Engel fridge, so I'm thinking I may not benefit from the added expense of an MPPT controller.

thanks!

Mike

 

[slakrboy]

I suggest you read this blog in it's entirety.&nbsp; Its long but will save you hundreds if not thousands of dollars.&nbsp; I used his insights and experience to install a solar array on my Teardrop trailer, it charges the battery better than the built in charger does (and A LOT faster).<br /><br />http://handybobsolar.wordpress.com/<br /><br />He has a lot to say about PWM and MPPT.&nbsp; Long story short, unless you are using high voltage panels and/or have more than 600 watts worth of panels, you gain nothing by using MPPT.&nbsp; I have a PWM controller BTW.<br /><br />

 

[SoulRaven]

Please we are only talking a $100.00+ MPPT controller... This is a controller which is a smart controller and handles all levels of voltage in and converts this to 12 volt with higher amps to the battery... All you have to be concerned about is that the controller can handle the watts of the input panel ...<br /><br />Stay away from PWM controllers, they are a waste of money...<br /><br />Some really have to be silent about things they have no clue about... Slak

 

[kevinr]

Thanks for the link Slakr. SR is resorting to ad hominem, but I think he might be right. Check this out: <br /><br />Silence, by the way, is the slow way to learn. Keep speaking up. Dare to be wrong.<br /><br />In any case, this is an interesting thread. <br /><br />Kevin<br />-Self-Elected Logical Fallacy Patrolman <img src="/images/boards/smilies/smile.gif" border="0" align="absmiddle">

 

[twokniveskatie]

Kevin! Thank-you, your remarks about learning are spot-on.&nbsp;<br /><br />Slakr- what Kevin said. We're all about throwing out info and helping each other figure it out. We don't always agree, and we don't always get it right.&nbsp;<br /><br />We do always try to be nice. Sometimes, there is a learning curve for that, too.&nbsp;

 

[akrvbob]

The cost difference between MPPT and regular controllers is so little now, I think you should buy an MPPT. Plus, you never know what your future needs may be. I have been using a BZ250 MPPT controller for the last 3 years and it works great. You can get it online for $133, how much cheaper do you want? <br /><br />I know it will handle panels up to 36 volt since my friend Steve has a 36 volt panel he is using with his BZ250.<br /><br />For your simple needs I think a 135 watt panel and the BZ250 would work great. I have a pair of Full River AGM golf cart batteries and I am extremely happy with them. Best batteries I've ever had. BUT, they are very expensive. I got them in Quartzsite, AZ. Bob<br /><br />

 

[gadgetMe]

<br />Thanks for the info on the mppt Bob.<br /><br />Since I cannot ever leave well enough alone, I just purchased another 2 panels from Kyocera,<br /> ( for my little put-put boat soon to turned alt energy boat)<br />I think I will get the BZ250 you suggest, <br />The one in the suburban is a prostar 15 amp pwm, if the BZ works better the prostar may become backup status..<br /><br />Not to change the subject but I did a little more research on the panel prices and found out that with the kyocera brand solar panels they are manufactured in California and Mexico so they are exempt form the trade war.. <img src="../images/boards/smilies/smile.gif" alt="" align="absmiddle" border="0" /><br /><br />Hope you are well<br /><br />Putz

 

[akrvbob]

My goodness Putz, are you trying to corner the market on solar panels all by yourself!! We just finished the RTR in the Sierras and I thought about you. I'm really sorry we couldn't do it in Colorado and get to see you again. Hopefully next year. We used your fire poker and I told everybody the legendary tale of how the mighty putz formed it out of rebar with his bare hands like it was a toothpick (I may have exaggerated a little!). It still works great! <br /><br />To keep this post a little on topic, I think I told you I was planning to put a solar panel on my tow vehicle. If so I think I will buy a BZ500 controller. It handles 45 amps and I think even higher voltage. It also comes in its own box. I don't think it is that much more money, but does a lot more. The way you keep buying solar panels you may want it instead of the 250.<br /><br />I've noticed that the Kyocera panels haven't gone up in price, you can still get some house sized panels from them for great prices. i have a friend setting up a system now so that is what I recommended to him.&nbsp;<br /><br />Can't wait to see you and the Tike Bar again at the RTR! Bob

 

[Guest]

Here is the follow up video... this explains and demonstrates what SR was saying.<br /><br />[video]

 

[Gump]

I use an mppt500. I managed to blow it up in a ball of blue fire the first time I tried to set everything up, but the dude who runs BZ replaced it for me for free. Got it working now, and it's pretty awesome.

 

[VanTrekker]

<img src="https://lh6.googleusercontent.com/-...AAABRw/SCUlCARhJGw/h120/Charge+Controller.jpg" alt="" /><br /><br />I've been using a <span style="font-family: 'Arial','sans-serif'; mso-bidi-font-size: 12.0pt;" lang="EN-US">PCM3012&nbsp; MPPT charger (about $140 including shipping)... Got it from Ebay.&nbsp; So far it has performed perfectly.&nbsp; I'm using a single Astroenergy higher voltage 235 watt panel - the MPPT saves a lot of wasted power.&nbsp; <br /><br />Most days the panel/ controller combo&nbsp;is pushing up to 15 or more amps, sometimes close to 20...&nbsp; What's really cool is when the charge controller throttles back to float stage when the battery bank is full.&nbsp; A voltmeter in the sleeping area lets me monitor the house battery level at all times.&nbsp; Solar is fun stuff and there's lots of good advice on here...<br /><br />Have fun!</span>

 

[cedric]

Ok that video helped immensely. thanks