Newbie -hard learner

[gray webber]

Hello!
Already posted some on this forum. Have learned a great deal from members.
I’ll take a moment to explain my solar goals in case some here will pitch in some knowledge I can benifit from?
My project:
Off grid camp on 24 A and creek-love the land.
1600 watt load per day
Limited winter use but winter here is 6-7 mo.
1760w -4panels Bi-facials
Midnight solar combiner box. 2s and 2p
Midnight Solar classic 150 charge controller
Victron Multiplus 24-3000-70 inverter charger
2-12volt 300ah lithium iron ion batteries
Insulated heated battery box in solar box -90ft from camp
Main issues yet to figure:
1. Love the info Victron BMV 500 provides but blue tooth service of 100ft is a big issue
Working to find answer that will work. Could use Renogy BMV but need to run another cable?
2. In case heated box fails then low temp shut off for solar is needed. Thinking maybe 40amp remote bulb thermostats set to shut off PV strings if box drops below 35f?

My friend a neighbor is setting up a very similar system to upgrade his 4year old lead acid wind assisted system. No more wind. Same battery bank and box. Samlex 2422 inverter charger. Changing panels from 8-100w and EPEver 60a to the same PV as mine.

Any input is appreciated.

 

[Bud Martin]

OP: 1600 watt load per day
Please clarify that, is it really 1600W-Hr per day? or 1600W load for X hours?

 

[OffGridInTheCity]

Hello!
Already posted some on this forum. Have learned a great deal from members.
I’ll take a moment to explain my solar goals in case some here will pitch in some knowledge I can benifit from?
My project:
Off grid camp on 24 A and creek-love the land.
1600 watt load per day
Limited winter use but winter here is 6-7 mo.
1760w -4panels Bi-facials
Midnight solar combiner box. 2s and 2p
Midnight Solar classic 150 charge controller
Victron Multiplus 24-3000-70 inverter charger
2-12volt 300ah lithium iron ion batteries
Insulated heated battery box in solar box -90ft from camp
Main issues yet to figure:
1. Love the info Victron BMV 500 provides but blue tooth service of 100ft is a big issue
Working to find answer that will work. Could use Renogy BMV but need to run another cable?
2. In case heated box fails then low temp shut off for solar is needed. Thinking maybe 40amp remote bulb thermostats set to shut off PV strings if box drops below 35f?

One idea....
A Midnite Classic 150s has a temp sensor and AUX1 relay (I use my AUX1 to turn my inverter on/off at various voltages).
You can access the internal registers via custom software over the internet connection to the Midnite Classic and based on the temp sensor could decide to set AUX1 on/off to trigger an external relay to turn the battery on/off.

Not sure if you want to go custom software route - but here's what PHP looks like to access the battery temp sensor Midnite register via public domain modbus software to give you an idea. It takes attention to detail but not huge amounts of difficult code.

include_once("modbus/ModbusMaster.php");
include_once("modbus/ModbusMasterTcp.php");
include_once("modbus/ModbusMasterUdp.php");

// Connect to the Midnite Classic
$modbus = new ModbusMaster($ip, "TCP");

// Battery Temp Register = 4132
$recData = $modbus->readMultipleRegisters(0, (4132 - 1), 1); // $regNum + 1, so we minus a 1

// Battery Temp - divide the register value by 10 to get the proper value..
$ret = ($recData[0] <<8) + $recData[1];
$ret = substr($ret,0,strlen($ret)-1).".".substr($ret,strlen($ret)-1,1); // insert a decimal point '.' 1 digit from the right

// "6505.1" occurs when sensor is not hooked up to classic.
if(($regNum == "4132") && ($ret == "6505.1")) { $ret = 0; }

 

[gray webber]

OP: 1600 watt load per day
Please clarify that, is it really 1600W-Hr per day? or 1600W load for X hours?

1.60kw per day 24 hours.

 

[gray webber]

One idea....
A Midnite Classic 150s has a temp sensor and AUX1 relay (I use my AUX1 to turn my inverter on/off at various voltages).
You can access the internal registers via custom software over the internet connection to the Midnite Classic and based on the temp sensor could decide to set AUX1 on/off to trigger an external relay to turn the battery on/off.

Not sure if you want to go custom software route - but here's what PHP looks like to access the battery temp sensor Midnite register via public domain modbus software to give you an idea. It takes attention to detail but not huge amounts of difficult code.

include_once("modbus/ModbusMaster.php");
include_once("modbus/ModbusMasterTcp.php");
include_once("modbus/ModbusMasterUdp.php");

// Connect to the Midnite Classic
$modbus = new ModbusMaster($ip, "TCP");

// Battery Temp Register = 4132
$recData = $modbus->readMultipleRegisters(0, (4132 - 1), 1); // $regNum + 1, so we minus a 1

// Battery Temp - divide the register value by 10 to get the proper value..
$ret = ($recData[0] <<8) + $recData[1];
$ret = substr($ret,0,strlen($ret)-1).".".substr($ret,strlen($ret)-1,1); // insert a decimal point '.' 1 digit from the right

// "6505.1" occurs when sensor is not hooked up to classic.
if(($regNum == "4132") && ($ret == "6505.1")) { $ret = 0; }

I’m sure your right but I’m not going to program it-screw it up then lose 2600$ batteries.
Thank you for your time!
If I could find 20 amp 90volt DC plus mechanical remote bulb stats then one on each string would shut down PV charge if heater fails and stats sense 35f or less.
Old school-knuckle dragging.

 

[Bud Martin]

1.60kw per day 24 hours.

Do you mean your load is 1600W and you run it for 24 Hours, then that will be 1.6KW x 24 Hr = 38.4KW-hr per day.
1.6KW -Hr per day means your load is about 67 W and you run it for 24Hr.
1760W worth of panels with 5 hours of usable peak Sun will produce 8.8KW-Hr per day, but in real world it will be 75 ~ 80% of that amount.

 

[gray webber]

My load is:
.2kw lights
.8kw refridge
.2kw tv
.2kw coffee
.2kw extras
Per 24hours or 1.6kw for whole day.

 

[Bud Martin]

My load is:
.2kw lights
.8kw refridge
.2kw tv
.2kw coffee
.2kw extras
Per 24hours or 1.6kw for whole day.

That is 1.6KW of loads, so if you leave them on for 24 Hours, then you will be consuming 1.6KW x 24 Hours = 38.4KW-Hr per day, but not likely that you will leave all the loads on for 24 Hours, right?

 

[gray webber]

I see where you see that but it’s the accumulated daily load of 1.6kw.
IE:fridge uses .8kw for the whole day.
Or 290 KWH per year.

 

[DixieMtCR]

Yes, you need to have the capability of producing the amount of power needed to run your stuff at any given time. All that power added up is called watts.

But then, the amount of power you need to be able to produce to run the stuff and hours to run that stuff is call Kilo-Watt-Hours. That is, (Total Watts to run my stuff) times ( # of hours i need to run that stuff).

Sounds like maybe the terminology is a bit confusing. Bud has the daily consumption/need correct in saying
1.6KW x 24 Hours = 38.4KW-Hr per day,

I have 1200w of panels, but only 5hrs of sun this time of year. So, I can produce only
1.2kw * 5hrs = 6 KWh. I really have to manage my usage or the system will go down.

BTW, 1200w of panels will never produce 1200w of power. Not 100% efficient!

 

[gray webber]

Yes, you need to have the capability of producing the amount of power needed to run your stuff at any given time. All that power added up is called watts.

But then, the amount of power you need to be able to produce to run the stuff and hours to run that stuff is call Kilo-Watt-Hours. That is, (Total Watts to run my stuff) times ( # of hours i need to run that stuff).

Sounds like maybe the terminology is a bit confusing. Bud has the daily consumption/need correct in saying
1.6KW x 24 Hours = 38.4KW-Hr per day,

I have 1200w of panels, but only 5hrs of sun this time of year. So, I can produce only
1.2kw * 5hrs = 6 KWh. I really have to manage my usage or the system will go down.

BTW, 1200w of panels will never produce 1200w of power. Not 100% efficient!

Sir,
You are correct of course but I was not understood.
Ref-900watts per day
Lights-200watts per day
Micro-200 watts per day
Pump-200 watts per day
Other-300watts per day
Max-1800 watts per day
Not per hour as these items run short times each day.
I have 1800 watts Solar PV. 300ah 24volt batteries.
I am leaning towards going to 2700 watts by over paneling for poor winter Solar. Discovered my Midnite Classic will be ok doing this and in summer I can shut down extra PV.
I am learning fast and feel I have many answers thanks to all the folks on this forum.
Thanks!