BZ MPPT250 charger controller deal

[cedric]

I found/purchased this online after getting some good advise on this forum.<br /><br />$132.81 + $15 shipping<br /><br />http://www.gogreensolar.com/product...ontroller-25a-12-vdc-flush-mount-no-enclosure<br /><br /><br />

 

[wrcsixeight]

<a href="https://www.google.com/search?q=BZ+site:wind-sun.com">https://www.google.com/search?q=BZ+site:wind-sun.com<br /><br /></a>

 

[SoulRaven]

BZ is also on Ebay and have great deals...

 

[cedric]

I couldn't find any on ebay. Is there a different name to search?<br />I really wanted the mppt500 but can not afford it yet.

 

[cedric]

oh wow, <span class="status_offline" title="Offline"><a href="/profile/1980243">wrcsixeight</a><br /><br /><br />I just read some of the threads from the google search you posted above. <br />I hope BZ products don't suck or I'm out $150! Some of those threads were yr 2010 so I'm in hopes they improved.<br /></span>

 

[SoulRaven]

Cedric, make sure to add the wattage of your panels and be sure you do not go over the wattage the controller can handle.... As a rule ya wanna stay about 20 watts under the max rating to be safe...

 

[cedric]

thanks soulraven I will

 

[wrcsixeight]

I've found the knowledge base on the Arizona Wind and Sun Solar forum to be very impressive.<br /><br />But we know how incorrect rumors can persist or multiply in this day and age. &nbsp;Many think Quaker State or Pennzoil motor oils cause sludge in engines, when that has not been true since the early 80's, and affected most every oil type back then. &nbsp;Those two were just the 2 most popular then, so had the most sludge reports circulated.<br /><br />Both of those oils today are among the best conventional oils at preventing sludge, but I hear time and again from old timers how sludge prone they are.<br /><br />I chose to not take the chance on BZ and spent the extra for A BlueSky SB2512i. Too many times I have shot myself in the foot when trying to save a few dollars.<br /><br />&nbsp;

 

[akrvbob]

When I bought my system from Solar Mike at the Slabs I noticed he ran his office system with a BZ 500, so I bought a BZ 250 from him. Having owned a BZ 250 for 4 years, getting a friend to buy a BZ500 3 years ago and another friend to buy a BZ250 this year, I'm a big fan of BZ controllers. <br /><br />I think the Blue Sky is a better controller (at least that's what Mike told me)&nbsp; but it is at least twice as much money (probably more) and they both come with a 5 year warranty.<br />Bob

 

[bee]

Am I wrong or is this not a 3 stage controller?&nbsp; Wouldn't someone be better off with a 3 stage like <span class="productnamecolorLARGE colors_productname">Morningstar TS-45?&nbsp; I don't personally have one but I think I remember hearing that it has adjustable voltage setpoints so you can actually charge your battery at the proper voltage. </span>

 

[SoulRaven]

Bee, the BZ family of controllers are all self adjusting to include input voltages up to i think 60 Volts... The battery is charged at the maximum level of the battery (Monitored) till full and then trickle charged until power is used or the sun goes down...

 

[akrvbob]

Bee, what I think you are talking about is called the "Float Point". When a battery comes up to its proper voltage, the controller cuts off power. Most batteries want to float at about 14.4 volts. But, different batteries and manufacturers want a different float point. So most good controllers will let you adjust the float point from about 13.8 to 15 volts. The Bz controllers will allow you to change float point within that range. Bob&nbsp;

 

[wrcsixeight]

Holding 13.8+ volts after a &nbsp;flooded battery is fully charged will substantially increase water consumption and degrade the plate material faster. &nbsp;It is temperature and battery brand specific, but float voltages usually range from 13.2 to 13.7.<br /><br />Acceptance voltages are usually 14.4 plus. &nbsp;It is very difficult to squeeze in the last few percent into batteries. &nbsp;Acceptance voltages at tapering amperages and time are needed to do it.<br /><br />Bulk charging raises the battery voltage as the battery state of charge rises. &nbsp;It rises to the acceptance level on three stage chargers, and the batteries are likely at the 90% stage once this voltage is reached, through the solar. &nbsp;Higher alternator amperages can attain these voltages at lower states of battery charge.&nbsp;<br /><br /><br />Equalization voltages(intentional overcharging to balance all the cells) is usually 15.2 plus.<br /><br />The higher the temps the less voltage needed. &nbsp;The lower the temps the higher the voltages needed. &nbsp;Charge controllers with battery temperature sensors are recommended.<br /><br />Each battery company lists slightly different voltage setpoints for bulk/acceptance/ and float charging. &nbsp;They also change these numbers as time goes on as they figure out what works best at reaching maximum specific gravity.<br /><br />A glass hydrometer that looks like a turkey baster is really the best tool on a flooded battery to determine it the voltage setpoints are indeed bringing the battery to full charge. &nbsp;The cheap plastic ones are near useless, because bubbles stick to the float skewing readings. &nbsp;The floating ball hydrometers are a joke.<br /><br />I set my acceptance voltage to 14.8 and hold it for 1 hour, but if I am dragging my batteries lower than I normally do overnight, 2.5 hours at 14.8 is needed to get the specific gravity at or above 1.275 across all the cells.<br /><br />Battery charging is an evolving science one can take to ridiculous levels, or one can just hope the system knows what is best and the batteries perform well for a long time. &nbsp;Sometimes there is no choice, depending on the equipment and it's limitations.<br /><br />Usually, with solar, one does not have enough time or wattage or sunlight anyway.<br /><br />

 

[jonsun]

<p>Morningstar (tri-star or Pro) are about the best controllers out there. No these BZ things don't have voltage sense.</p>

 

[bee]

<p>Generally wet deep cycle batteries are designed to bulk charge at 14.8v.&nbsp; Then ideally they will be placed on a maintenance voltage of around 13.4<br />Controllers like the <span class="productnamecolorLARGE colors_productname">Morningstar TS-45 </span>I mentioned before will do this with their adjustable charging profile. This means that assuming you have the solar panels to back it up a morningstar controller will charge much much faster then the BZ controllers that lack this feature.<br />Unfortunately we usually don't have the solar panels to back this up, but I am still inclined to choose the better charge profile of the morningstar over mppt on the BZ considering they are about the same price.</p>