2 chargers

rolandc20142014

i have a solar charge/controller -average cost and quality Solar Boost 2000E Multi-stage Pulse Width Modulation (PWM) and one 55 amps Iota with IQ 4 ... question sometimes i am grid plugged in and there is the sun also charging ... is it safe or should i unplug the Iota untill the sun goes down

thanks
love to learn and i am in fact 'loyning a lot' like louis darcy would say loyning a whole bunch and lovin' it ... do not know all of yous djet but cariboo stands out already ... great forum ... not buttering you up for an answer ... i mean it plus i have always been the suck up type anyhoo ... but not this time ... i mean it .. hihihih

BB.

Re: 2 chargers

Welcome to the forum Roland!

My first suggestion would be read all about batteries:

http://www.windsun.com/Batteries/Battery_FAQ.htm
http://www.batteryfaq.org/
http://batteryuniversity.com/

After you read the above, you will conclude that Lead Acid Batteries do not work for off grid power.

In reality, they actually to work surprisingly well--It is just there are a dozen ways to kill a lead acid battery bank. Over charging, under charging, charging with too little current, charging with too much current, not adding enough distilled water, adding too much distilled water, too small of battery bank, too large of battery bank, not keeping connections clean, cleaning too much and getting baking soda inside cells, too cold of battery will not output as much energy (but last longer), too hot of battery will output more energy but not last as long...

What it comes down to with battery chargers and your bank--Monitor battery voltage with a good volt meter, monitor the specific gravity with a hydrometer and log temperature corrected specific gravity (once a week to once a month). Monitor electrolyte level (using too much water--needing to refill once a month or more often--probably over charging; not needing to add water every--Probably under charging).

In general, if the charge controllers are all probably wired and configured, you can run charger in parallel. Batteries care "mostly" about the charging voltage (bulk/absorb/float). They also care about current--Around 13% maximum charging current is not a problem. If you have 20-25% charging current, you can overheat the battery bank (good charge controllers will have a remote battery temperature sensor--Hot batteries need lower charging voltages).

So--It all comes down to specifics... What is the Battery bank Voltage/AH rating/Battery type (AGM, flooded cell, etc.).

What is the size of your solar array and Iota chargers. What is the voltage set points for the chargers. How much discharging do you do on your battery bank (daily, almost never, etc.)...

So, read about the batteries. Measure the battery bank voltage (resting, charging, discharging). Measure the specific gravity of each cell (and log). Then figure out were to go from there (more/less charging, perhaps reconfigure chargers if cables are too long/too small of diameter, etc.).

-Bill

westbranch

Re: 2 chargers

FYI,the 2000e is an MPPT charge controller not PWM. It is old technology and has some distinct limitations for max. input amperage, less than 20Amps Isc.


section 4 page 2 of manual
h)
Do not connect to a PV array capable of producing greater than 20 amperes of short circuit current (ISC) or 24V of open circuit voltage (VOC) @ STC.

rolandc20142014

Re: 2 chargers

thank you ... great site that university

rolandc20142014

Re: 2 chargers

thank you ... i meant to say what i did not write .... hihihih mppt it is ...