phantom draw; MS Classic 150

[outwestbound]

Hi. My purpose is to control about 960 watts of 12V panels on the roof of a fifth wheel travel trailer.

I'm evaluating a purchase and "I'm hearing" from vendors various opinions.

I need to maintain the lowest draw of power to run my controller. I'm comparing the Midnite Classic 150 MPPT to stacking 2 Morningstar TS MPPT 45s.

Which configuration would burden my solar system more, in terms of power to run itself?

I gather the Classic 150 has a fan whereas the alternative is a passive heat dissipater. 

[ClassicCrazy]

The fan on the Classic only runs when it gets warm enough - not all the time.
So a lot of the efficiency of either controller you choose is going to be based on your system design. If you have the input voltage closer to the battery voltage your controller won't get as hot and the controller should make less heat and be more efficient.

If you are asking about standby power use at night - I don't know the specs on that.

But when you calculate energy use, consider what you want to use for monitoring your system. You get a lot of bang or the buck with the Midnite Classic with Local Status App , Mymidnite online , and Android apps for monitoring.

The other consideration is if you want to control loads - the Classic has built in aux relays to turn things on and off. And the Whizbang add on gives so much more control and monitoring capability .

The fan noise is a consideration in a small space though , while it isn't terribly loud - it is there. But all in all the Midnite is the controller to get. You can also stack Kid controllers I believe so consider those too if you don't want as much remote monitoring options.

Check out this Kid vs Morningstar comparison
http://midnitesolar.com/images/frontPage/PSvsKID.pdf
Larry

[estragon]

I think the standby (resting) draw on the classic is ~ 5 watts.

[boB]

Idle draw power has been going down and down over time...
Lowest I have seen it is around 2.8 watts.

3.5 watts fairly typical these days I think.

Been a while since I have  checked though.

If you don't use the Arc Fault, you can actually turn off its power and save almost a watt.

The MNGP draws a fair amount too  though.  Like, a watt or so.

boB

[CDN-VT]

Hi. My purpose is to control about 960 watts of 12V panels on the roof of a fifth wheel travel trailer.

I'm evaluating a purchase and "I'm hearing" from vendors various opinions.

I need to maintain the lowest draw of power to run my controller. I'm comparing the Midnite Classic 150 MPPT to stacking 2 Morningstar TS MPPT 45s.

Which configuration would burden my solar system more, in terms of power to run itself?

I gather the Classic 150 has a fan whereas the alternative is a passive heat dissipater.

Im sure you won't always have 12Vdc panels & might upgrade to a higher voltage & maybe more efficient panels  , then You have not limited yourself. The fans only run when warm & harvesting huge power.

After a while , you will love the fan sound !! AS I Do !!

VT

[russ_drinkwater]

I must say I find the sound of the fan comforting as well, Lol.
The efficiency of the midnite far out weighs any minor power draw it has.
And the MPPT really works a treat.
Even on cloudy days with little obvious PV production the batteries are always well cared for and
maintained to the highest level.

[sigp2101]

Even on cloudy days with little obvious PV production the batteries are always well cared for and
maintained to the highest level.

It is so encouraging to read that. Gives me a hope that my BB will survive winter.

[russ_drinkwater]

I have been playing with the shade on/off setting in the controller just to see if it makes any difference on the occasional cloudy days.
My wife now knows to look at the SOC on the classic if the weather is getting worse and she switches to grid tie if 80% or using
extremely high draw appliances on the over cast days. The classic 150's are doing a great job and I can not wait to get the last one up for the big bank and have a a follow me tag team going with 2 of the units! I know I am under panelled at 4400 watts, but the inputs from the arrays is far in excess of what we use in a day! I should be able to squeeze 80 amps at 24 volts out of them during summer for over 5 hours a day.
We will see how good the regs are once full array loads are running!