A CLASSIC PRODUCT ADDITION ???

[Barry Fields]

A CLASSIC PRODUCT ADDITION?
My intent here is not to step on any toes, but to be honest, forthright and constructive.

Background
My belief is that many of your Classic users may have similar problems that I have.
 
My system is 3200watts of PV going to a Renogy Rover 60 (MNMPPT60DIY equivalent ? ). I have 4ea 215AH 48v FLA battery banks. My "load management" is accomplished thru multiple op amps, comparators, 555 timers and relays. I have to constantly readjust things because temperature compensated set points and other variables are unavailable. I would love to do end amps(WBjr) and PWM.
 
I could upgrade to a Classic 150 for approx $900 self installed. I sure it would improve my reliability and charge current capacity. I presently do not totally use the PV and charge capacity of the Renogy. I have little room or location for additional paneling (also an additional expense).

One Classic would not allow me to do both end amps and PWM. The present solution would be to purchase a second Classic to accomplish this. The additional charge current would be un-used as I have no wind or hydro (another expense).

I would also like to independently monitor each of the battery banks for SOC and float current trends (battery health). I would also like to do float current adjustment of absorb time (enough but not too much).

I realize the some Classic users are employing rasberry-pi and other mini computers to accomplish what the Classic will not. This is all well and good but beyond the scope of many user's abilities.

The real world suggests that a redesign of the Classic is less than desirable. It is not broke, it just has limitations.

I would suggest a new Midnite product to attach to the modbus (unique address). It would include the following:

1)  An upgraded ADC to monitor and combine up to 4 independent bank shunts with better resolution than WBjr. The increased resolution would assist in LIPO4 charging,  float current discrimination and tighter setpoint and width settings. Hopefully real time current data could be supplied over modbus and free up the Classic's aux2 port.
2) A "small" mcu to process ABSORB and FlOAT commands and LOAD engage/disengage commands for # additional AUX ports. I say small because these commands take place over minutes not milliseconds. It could be called upon to generate PWM signals.
3) Minimally it would have modbus connect-ability and USB for firmware upgrades.
Open question would be where to get power for the unit.

I am sure that peeps might want to suggest other load management parameters than I have suggested. Those should be customizable thru MNGP. Having reviewed the Classics registry I believe that all necessary parameters are available and can be written too.

I hope this post has not endangered my most recent promotion to Full Member.
Open for input
Barry

[Wizbandit]

Having worked for Midnite close to over 12 years now I think I can safely say the Classic line is getting close to EOL (End Of Life), I still have CL150 serial #829 on the shelf.  Let's face it, it uses older design parts (Transistors aka FETs) and the Classic runs REALLY, REALLY Hot and it does not take much abuse to short out the FETs.  The case is part of the heat-sink for the FETs.  In my power room with no A/C I have 4 Classic 200's and it gets over 95 degrees in the summer, I know better than to put my hand on one.

Rumor time, there may be a Classic 2.0 in the design phase right now, it would make better sense to think about this stuff being done to it before the final design. (The project has a code name but I can't remember it since the engineer working on it also designed the KID I just call it "The BIG KID", unofficially of course)

Right now the Hawkes Bay 90 is the best replacement for a Classic, it uses newer technology like Silicon Carbide transistors which are more powerful and run way, way cooler.  The HB90 also is a HV controller which means no more combiner box, most times all PV modules can run in one string or maybe two and more power from less losses.  It also uses a better MNGP called the MNGP2 and uses CANBUS for all the communication needs.  I know it costs more than a Classic but it is bigger, better and cooler.  The only thing is it is 48V only.  I heard rumors of maybe a 24V version some day but I'm not sure, it would need to drop down in current to keep the same terminals.

The cost is around $1250 retail:
https://www.currentconnected.com/product/midnite-solar-mnhawkes-bay-90/

[Barry Fields]

Am I correct in saying that the Hawksbay also requires a higher PV input voltage? (re-config/add solar panels)
Can it perform any of the above load controls I have described above?
Does it also have the same restriction that WBjr uses one of the AUX ports?

IMHO not a clearly advantageous upgrade especially for a 12 or 24 or 36 volt user.

Could be an "capability expander" I have describe above could also be of use to a Hawksbay installation.

[ClassicCrazy]

Am I correct in saying that the Hawksbay also requires a higher PV input voltage? (re-config/add solar panels)
Can it perform any of the above load controls I have described above?
Does it also have the same restriction that WBjr uses one of the AUX ports?

IMHO not a clearly advantageous upgrade especially for a 12 or 24 or 36 volt user.

Could be an "capability expander" I have describe above could also be of use to a Hawksbay installation.

Hawkes Bay does need 185v lowest possible pv input and 48v battery .
I believe the PWM is available on both of it's aux at same time  , and don't believe the whizbang ties up either or the aux .
Larry

[Barry Fields]

Again something I do not know:

Can the existing Classic 150 be "firmwared" to do Canbus instead of modbus?

[ClassicCrazy]

Again something I do not know:

Can the existing Classic 150 be "firmwared" to do Canbus instead of modbus?

I don't think the Classic has the communications hardware needed to do canbus. It is different than what the Classic modbus does via IP or over the jacks to the MNGP.
Larry

[boB]

The Classic doesn't have a CAN peripheral so it wouldn't be able to do it.

It also doesn't have the CAN BUS driver chip.

[Wizbandit]

Since Barry likes education I will try and explain MODBUS and CANBUS.

MODBUS uses a client-server topology. The client "asks" for data and the server, well, "serves up" the data.  Let's say REQUEST & REPLY.  The Classic uses 16 bit registers, think of a register as a box that holds data. 8 bits forms a "byte" so the Classic MODBUS register is 2 bytes long.  Some Classic data won't "fit" in 2 bytes so we combine two registers and use 4 bytes but we need to read each register and combine them for our data.  Classic lifetime KWh register comes to mind, it's 4 bytes or 32 bits. The cool thing about reading MODBUS we can select an address (MODBUS registers all have an address used to access them) and pick how many to read so for a 32 bit piece of data we can read 2 registers in one swoop, then process them into our data.

If still interested I'll explain CANBUS next...

[Barry Fields]

I do indeed like edumacation. Please continue.

Just so I am clear, would the second Classic or the proposed new box be the client?

[boB]

I do indeed like edumacation. Please continue.

Just so I am clear, would the second Classic or the proposed new box be the client?

The Classic with MNGP has both a client and a server for instance.
The MNGP I guess you would say is the Client.  It asks the Classic for information but can also write new values to the Classic.  So the Classic would be a server in that case, I guess.

Now the Classic can also be a client and ask other modbus devices for information and change their register values so it can also be a client.  That would be like when it is doing Follow-Me.

The Classic does not spit anything out over its modbus ports unless asked, except for some Follow-Me data exchanges.

[Barry Fields]

Is the communication between MNGP and Classic also modbus?

[boB]

Is the communication between MNGP and Classic also modbus?

Yep.
In fact, you can plug the MNGP into the top RJ11 jack OR the middle jack.  The middle jack only uses 4 out of 6 connections so the middle jack will not light up the 2 bottom LEDs on the MNGP

[Barry Fields]

I will not sing it but, anything MNGP can do the new box could do better. 

[Barry Fields]

Question?

First we need to name this potential new product. I would suggest BBMT (Barry's Better Mouse Trap).

Presently the Classic has a voltage discrimination of .1 volts. TRUE?
Could it be best to include a better ADC in the NEW BBMT for more precise trigger voltages?
Can the Classic "handle" more precise set points and width voltages or should that task be better handled by the BBMT?

Humbly yours
Barry

[Barry Fields]

in addition to the above questions,

Do the hawksbay and barcelona also use modbus to communicate?