whiz bang jr and classic 150

[new2PV]

Silly question If I have a classic 150 and no other charger do i still need the whizbang jr shunt?

[Vic]

Hi new..,

YES.   The Shunt is placed in the negative battery lead,  so the WBjr can measure the current that is going into and out of the battery,  and report this information to the Classic.

The Classic has an accurate Shunt built in,  and accurately measures the current that flows out of its output terminals,  but cannot know how much of that current is actually flowing into the battery as charge current (inverters and other loads consume current that is not battery charge current).   And the Classic cannot measure current that is removed from the battery and flows to the inverter and other loads.

The ability of the Classic to monitor the comings and goings of battery currents allows it to track,  fairly accurately the SOC,  and very accurately the AH removed from the battery,   etc.

FWIW,    Vic

[new2PV]

Thanks Vic, I just was not sure how it all worked.

[new2PV]

Ok the whizbang connects to the AUX 2 functions, so now I lose any other features that i could use for something else, not too pleased with that arrangement, why would the classic team do this?

[Halfcrazy]

Aux2 is a all in one terminal, It can be an Output or it can be an input. So if you use a WBjr it is used as an input. Not sure how else we would design it? There have to be some limitations on hardware or it would cost a fortune. Sure we could use a bigger processor and have 6 Aux's vs 2 but that's going to drive the cost up. I think we decided on 2 as that is more than others had. So even if you use Aux2 for WBjr or Clipper you still have Aux1

Ryan

[new2PV]

Ok, Ryan, i see where your coming from on added costs, but need 1 aux output to turn on and off my inverter based on battery volts over time. So since 1 and 2 are used how would I incorporate a diversion load?   I was thinking about using a 1kw 48v water heater element.

[Vic]

The Classics are High Performance boxes with many,  many bells and whistles built-in.

You could go to Morningstar CCs ...  OH,  right 60 Amps out max,  ...  right,  and NO AUX ins or outs at all ...  let me think   ..   Yea,  all of the other MPPT CCs I've seen have No Hyper Voc-type function,  and at most only one Aux,  and for those with an Aux,  it is only an input (to the best of my knowledge and recollection).   So by comparison,  IMO,  you have lost nothing.  But have gained a lot of free functionality.

The MidNite Team really has done a great job shoehorning in all of the terrific functions that the Classic has.

AND,  forget not,  that on the Standard Classics (not the Lites),   the WBjr is included FREE (at least in the USA).  This is a HUGE BONUS !!

In My Respectful Opinion,   FWIW,   Grateful Vic

[TomW]

Well said, Vic!

Feature bloat can ruin a good thing, IMHO.

There are probably several ways to fire off a dump load from another inexpensive device. A thing called the "Ghurd Controller" comes to mind as does the MorningStar relay driver. Both can trigger a relay or FET off and on based on voltage. Both are relatively cheap and easy to use.

Just some other options.

Tom

[new2PV]

Its interesting that the Apollo t80hv charge controller has a separate input for its shunt via modular jack and has 2 aux inputs and outputs that are available.

[dgd]

Looking at the Apollo t80hv spec sheet it says:

Auxiliary relays   ........................             Two independent relays with form A (SPST)
                                                               contacts for control of external devices. 
                                                               Configurable as NO or NC.  Contact rating ½ Amp, 50 VDC.

Nothing about Aux inputs of any kind nor PWM type output for controlling external SSR (often used for heating element control) or diversion/waste-not settings etc..
Am I looking at the wrong spec sheet?

dgd

[Halfcrazy]

The T80HV is designed to
withstand 200 Voc, run MPPT to 180V and to operate up to 160 Vmp.

I have never fully understood this either? It can run MPPT to 180 but only operate to 160?

But then the spec sheet says this: Maximum PV input voltage (Voc) = 180VDC Maximum Open Circuit Voltage (Voc), 160VDC Max Operating (Vmp) 

[new2PV]

Not sure about those voltage ratings but, I do like that it has 2 outputs, I don't see any inputs you are correct. I do like that i can turn on and off my inverter based on SOC and time, or  battery current,  or output current, or voltage.  Can the classic do all  this?

[dgd]

I though most decent inverters had auto turn on/off based on battery voltage (and hence SOC)
Why get the PV controller to do this? or is it to control a basic/cheap inverter?
I can't quite understand inverter on/off  control based on either battery or output current - has this something to do with load control? in that if a large DC load comes online then the PV controller can turn off the inverter to reduce battery loading? or perhaps a night time thing when load or output current is zero then switch off the inverter to save on tare load.

dgd

[new2PV]

My inverter can only be turned on and off via a 5 volt logic signal, it just has basic on off control, no other options. All the on and off control has to be done externally.

[new2PV]

Made a final decision to go with a midnight classic. I will make it work. The GFP and arc fault protection built in is more cost effective than any other controller.