Continued Tests of the 3 Battery System

[gotoluc]

Hi Luc,

I've been following your test. It appears the batteries are nearly discharged. I don't know how you will determine the end of test (EOT). With 6 cell lead-acid battery discharge tests I typically used 10.5V under load or 11.0 Voc (Volts open circuit) as a standard EOT. Once you get to that point there is not much energy left in the battery and further discharges to even lower battery terminal voltage is harmful to the battery.

IMO, a base line test would be nice to see. For instance a single fully charged battery running the same motor continuously until discharged to 10.5 or 11 V. Record run time and watt hours as well as V & I. I suspect it'd take about 35 hours. I don't see the need for rest periods but also see no harm in shutting down overnight and continuation next day.

Hey, I like what's going on here. Just throwing some suggestions your way from a guy who's done many, many battery tests.

Keep it up.

bi

Hi bistander

I have already explained in the first video that the two batteries (labeled A1 & B2) were fully charged at the beginning of the test and that Bat C3 was fully discharged which I also demonstrated to be so. I also explain bat A1 & B2 were load tested (charged & discharged) over 6 time and averaged 60 Watt/hr of capacity in each. I did also mention I'll stop the test if the motor stops or when all 3 batteries reach 10 Volts (which ever comes first) which at that point there should be no doubt that the batteries energy capacity we started with in bat A1 & B2 is fully depleted and then calculate the motors total run time hours.
We'll have a total Watts/hrs that has run through the 3 battery circuit.

The next test will be to recharge bat A1 & B2 and each run the motor (watt meter attached) till each battery reach 10volts then total the hours of run time.
We'll compare the data of the two tests and it should be clear if the 3 battery system makes a motor run longer then just connected straight to a battery.

Is there anything unclear about the tests?

Regards

Luc

[bistander]

Base line

Hi Luc,

I've been following your test. It appears the batteries are nearly discharged. I don't know how you will determine the end of test (EOT). With 6 cell lead-acid battery discharge tests I typically used 10.5V under load or 11.0 Voc (Volts open circuit) as a standard EOT. Once you get to that point there is not much energy left in the battery and further discharges to even lower battery terminal voltage is harmful to the battery.

IMO, a base line test would be nice to see. For instance a single fully charged battery running the same motor continuously until discharged to 10.5 or 11 V. Record run time and watt hours as well as V & I. I suspect it'd take about 35 hours. I don't see the need for rest periods but also see no harm in shutting down overnight and continuation next day.

Hey, I like what's going on here. Just throwing some suggestions your way from a guy who's done many, many battery tests.

Keep it up.

bi

[gotoluc]

11/3/17 (5th day) 25th bat switch

Link to video: https://youtu.be/172gJ-6xkrQ

[gotoluc]

Test resumed 11/3/17 (5th day) 24th bat switch

Link to video: https://youtu.be/ggSUcI70j-E

[Satyam108]

34.69

I am REALLY looking forward to the last test tonight, and here's the data so you can see why.

I'm going to put two columns of figures here. they are the last 7 tests. I totaled the voltage in the three batteries each time

35.22..........35.6
35.45..........35.52
34.12 ..........35.02
34.87

In each of these instances There is a low total followed by a HIGHER total. I have a feeling that ONE battery out of the 3 is not doing so well at taking a charge, just from what I see here. There is ONE weird number. But in all THREE of the complete pairs, the end number is higher than the BEGINNING number.

I get 34.69 Dave

[gotoluc]

11/2/17 (4th day) stopped for the night at 1:15 am

Link to video: https://youtu.be/cGa9Z4Bj5L4

[gotoluc]

11/2/17 (4th day) 23rd bat switch

Link to video: https://youtu.be/IDv5j6YQo5Q

[gotoluc]

Yes, I though of that as well. To power one meter it uses 0.00091 Amp @ 12vdc and 0.00134 Amp @ 24 vdc
Luckily the lab space I have free use of has a high end meter I can measure microamps with precision.
Like you said, it's not much but it's good to know and factor in if you wish.

Regards

Luc

Dave, the current measurement I provided you is only the current consumption of the Watt Meters circuit and LCD. It does not include what is dissipated in the Meters Shunt resistor which is either 0.001 Ohm or at most 0.01 Ohm

Regards

Luc

[BroMikey]

I wonder how much power those three meters
consume running the entire time the test is running? It might not be
much but it is certainly something.

yes you are right Dave this value could be added into the chart.

Here is a quote from a RC site on shunts as all measuring devices such
as shown in Luc's video's use built in ones. The one's Luc is using has
more functions for even smaller amounts to measure that drives the cost
up. I think DROK is one brand name if you wish.

For our purposes we only need the ma scale but either device whether
cheap or expensive carries an internal shunt. This is simple Ohm's Law
math if you want to calculate it out.

The built in shunt on the meter i am buying off of ebay

https://www.ebay.com/itm/AC-80-260V-20-50-100A-DC-6-5-100V-LCD-Digital-Display-Volt-Amp-Power-Watt-Meter/172621629117?hash=item28310d06bd:m:mqoXQnuea95tb0S E9664FSg

is lower at 20 amp size. They also talk about drift and calibration here.

it appears that what use to cost hundreds of dollars is now produced
for a fraction of that cost and is common place. Anyone can afford these.

According to all of the new standards you are looking at .002%+or-

i remember John Bedini use to harp on not using amp shunts with
his radiant chargers as they were all pulsing and surging constantly
and since he was working with a COP of 1.3 it was critical to keep
losses way down. Pulsing is another story, losses go higher.


http://www.rc-electronics-usa.com/current-shunt.html



Ohm's law:

V = I × R

states that the Voltage (V in Volts) across a resistance
(R in Ohms) is the product of the resistance and the current
I in Amps) flowing through the resistance.

For example. A current shunt whose resistance is 0.001 Ohms
having a current of 50 Amps flowing through it will produce a voltage
of 0.001 ×50 = 0.05 Volts or 50 mV (milliVolts).

So by inserting a current shunt into a circuit whose current you
want to measure your can find the current by measuring the voltage
drop across the shunt. Then knowing the resistance of the current
shunt you can calculate the current using Ohm's law arranged
as I = V ÷ R.

Conversely, if you know the current and the voltage produced
across a current shunt you can use Ohm's law to calibrate the
current shunt resistance.

[gotoluc]

11/2/17 (4th day) 22nd bat switch

Link to video: https://youtu.be/fIXUuAHkpSQ

[gotoluc]

I wonder how much power those three meters consume running the entire time the test is running? It might not be much but it is certainly something.

Yes, I though of that as well. To power one meter it uses 0.00091 Amp @ 12vdc and 0.00134 Amp @ 24 vdc
Luckily the lab space I have free use of has a high end meter I can measure microamps with precision.
Like you said, it's not much but it's good to know and factor in if you wish.

Regards

Luc

[gotoluc]

11/2/17 (4th day) 21st bat switch

Link to video: https://youtu.be/MsgvhZww0Fc

[gotoluc]

That's great Dave!... glad the test is looking promising

Regards

Luc

[gotoluc]

11/2/17 (4th day) 20th bat switch

Link to video: https://youtu.be/FfVDCSWDzGk

[gotoluc]

I accept your apology BroMikey and glad you now see my intentions are good.

Kind regards

Luc