I upgraded my solar panel from 40w to 120w and l would like to measure the rate it is charging at.
I am an electrical anti talent. I know it should be charging around 6w/hour or so.
How could l measure it? I got an ancient analog volt-ohm meter but l got no idea how to use it. I mean where to attach it at the regulator?
I post a picture of the thing l call regulator which is 8amp by the way. I was told, it would handle the new panel.
It seems to work fine just love to learn how to measure the charging rate.
All help would be gracefully appreciated.

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sirgallivant said..
I upgraded my solar panel from 40w to 120w and l would like to measure the rate it is charging at.
I am an electrical anti talent. I know it should be charging around 6w/hour or so.
How could l measure it? I got an ancient analog volt-ohm meter but l got no idea how to use it. I mean where to attach it at the regulator?
I post a picture of the thing l call regulator which is 8amp by the way. I was told, it would handle the new panel.
It seems to work fine just love to learn how to measure the charging rate.
All help would be gracefully appreciated.

I have no idea what that regulator would put through .But you might find some of the newer regulators and MPPT's put through more power to your batteries and also give you a LDC to read what your putting in . Thats my take on it I'm no guru with this stuff

Why not just wire in a permanent ammeter so you can look at it when ever you like and get an idea of how different days affect your power generation.

8 amps at 12volt equals 96 Watts. Might be a little small for 120 Watt panels??

A/ Regular is in fact Cut Off switch
simply to disconnect battery, when fully charge.

B/ Set your multimeter to voltage range and measure bat.voltage
when voltage gets up 14 V, unit will disconnect solar panels and voltage starts dropping
close to 13 V when the switch kick in again.

C/ In full sun, disconnect, bat. black ( Red Cross) , set you multimeter to current range ( 10A or 15 A )
dippends on model.........measure current going into battery......
..current measuring function is only momentary, means 20 sec. max,
as long you can read the value ....otherwise cooks current shunt inside
warning always return multimeter into voltage range after current measurement

MPPT is gimmick, if solar don't supply enough voltage wouldn't be enough curren, that's simple.
MPPT would be very good with Lithium batteries, because the accept small current charge,
lead bat. will not charge with small current.

The most important is instal digital voltmeter as a permanent fixture / for few bugs EBay/
and monitor voltage.

Voltage value under small load is indication of bat. charge.
....battery voltage is proportional to capacity....

( doesn't apply for Lipos, flat dischharge curve )

I thought the wattage was rated at the open circuit voltage, If the OCV is 20V and the power output is rated at 120W then this would be 120/20 = 6A.
not accounting for losses of course. not sure if it can be a straight extrapulation if you reduce the voltage to 13 odd volts via the regulator and therefore be 120/13.6= 8.8A

Hi Sirgallivant,
I have extensive experience with that Solarex regulator (used more than a hundred of them in equipment I designed) - although reliable, they are a very inefficient design. They are unable to operate continuously because of their poor thermal design, so the potential benefit of a protracted period of good solar conditions is wasted with this design.
If you want the most efficient solar system, have a look at the new MPPT designs.
Allan

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sirgallivant said..
I upgraded my solar panel from 40w to 120w and l would like to measure the rate it is charging at.
I am an electrical anti talent. I know it should be charging around 6w/hour or so.
How could l measure it? I got an ancient analog volt-ohm meter but l got no idea how to use it. I mean where to attach it at the regulator?
I post a picture of the thing l call regulator which is 8amp by the way. I was told, it would handle the new panel.
It seems to work fine just love to learn how to measure the charging rate.
All help would be gracefully appreciated.

In your quest for improved performance I would suggest tinned multi strand wire.

Dooh...
You guys are very helpful, no doubt, but you are trying to help a guy who is not even breeched as far as electronics are concerned. I have to google everything you mentioned. mppt? ldc? watts volts? It is all Chinese to me.

Ramona, I know, the supplier sent me best quality musty strand tinned wire. So that is done.

I got the message about the possible inefficiency of the regulator. I was thinking about getting a new one which displays the charging rate so l do not have to measure it, being on permanent display.

I got a four way battery switch ( see pic! ), and a three way flick-switch,so l can check the state of the batteries ( two110 amphr house and one 100 amphr starter, all newish agm's, the two house batteries lying on their sides. Would not fit otherwise.).
The two house bats are always around 14 volts while the starter n e v e r gets above 13 v. Different brands they are, thou.



LC, if l could tell negative from positive ( :o) ), I would. That is beyond me.

Datawiz, I got most of your explanation, thanks.

Riffraff, got most of it googled too.

Libran, chariot, I am still gasping but busily googeling what does not get across.

I am grateful for the helping comments, that l did or did not understand them is not you fault.
Though l am maintaining my yacht, the electronics throw me way, way out of my comfort zone.

A beer for everyone!

Sirgalli
Here is a web site that gives an explanation of MPPT. Who ever wrote it seems to have made it fairly simple to grasp. (but I am an electrical)

www.solar-electric.com/learning-center/mppt-solar-charge-controllers.html/

Also be very careful if you are using a multimeter to read current by connecting it in to the circuit. It may be better to get a clamp-on meter that is capable or reading DC current (some clamp on-meter only can do AC Current, like in the house power). Something like this from Ebay for $50. (I have one of these) You can also check charge current from alternators plus the rest of the things a meter can be used for.



I also purchased some digital Ammeters for my solar panels from J/Car and they don't operate as specified. I went back to J/Car and got F/all help. Its a pity because I had already cut the holes in my switchboard panel. They were Digital Readouts with a remote shunt. The shunt is like a high current, low resistance block of metal that the meter measures the voltage drop across. It allows you to check the current at the batteries or some other location where you mount the shunt and have the readout some where easy to see.

But you may like to invest in one of these from Jaycar for $150 for monitoring current in and out of your batteries. There are numerous other more expensive ones on the market. I have a Victron (brand) on my boat which seems to be okay. (the thing beside the meter is a shunt). Bit of trivia - they actually calibrate the shunt by cutting through the thin metal strips with a hacksaw until the correct resistance is achieved. (less metal left, higher resistance) (But don't you try it).

I think sirgallivant might be better of sticking to Chariots idea of monitoring volts only. Once you start playing around with ammeters and shunts you are having lots of amps behind the instrument panel or wherever you put that shunt. Cheap digital voltmeters off eBay.

I hope those batteries are well secured

sirgallivant, enough confused
Am I wrong, second on top left is nice voltmeter build in..?
If yes, is it working?
Learn to use it, it simple
In the evening, running light & no charge what voltage you see..
for instance just a notch under 12 Volts. 50% capacity left
what else you need to know.
this is most important info what condition is your system
switch the batteries over unles you run them in parallel

for the others ..solar panels are not typical power supply
...you can measure current without any load
and not blowing or shutting down protection
you see .3 volts on 8A, how is V * A = W apply ?

voltage available drops to nothing with the load comprende

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Charriot said..
sirgallivant, enough confused
Am I wrong, second on top left is nice voltmeter build in..?
If yes, is it working?
Learn to use it, it simple
In the evening, running light & no charge what voltage you see..
for instance just a notch under 12 Volts. 50% capacity left
what else you need to know.
this is most important info what condition is your system
switch the batteries over unles you run them in parallel

for the others ..solar panels are not typical power supply
...you can measure current without any load
and not blowing or shutting down protection
you see .3 volts on 8A, how is V * A = W apply ?

voltage available drops to nothing with the load comprende

Not Sure what it is on the left Charriot, but it definitely looks like in the middle of the grey switch panel.
As Charriot asked, is it working? If not, it would probably be easier to troubleshoot that one and get working again.

Gentlemen, l got a meter, volt amp whatever, l bought it ages ago and because l could not use it l gave it to my dad. He loved it, measured everything with it. Rebuilt bikes, fixed cars, houses etc. Well, he died in '94.
Pic 1.


I would not spend a brass razoo on another one as l am a total incompetent as far as electronics are concerned.
The switch board, like everything else, is working faultlessly, the wiring behind it is pristine.
Pic 2.


On the four way switch one can turn electricity on and off, select no1, both, or no2 battery.
On the toggle switch, (gee l am improving, l picked this one up on googly today) and the display shows no1 or no2 accordingly.
Also, it shows on my Navman,
Pic3.


and also on my chart plotter. It is alarmed, set to 11.5 volts.

If a generous soul would have the patience to tell me what adjustment on the volt meter l have to set, and on the regulator or controller,
Pic4.


which two of the three points l have to connect with the volt meter's pencil without blowing myself to kingdom come, to see how much is the new panel charges, would make me the happiest person on the boat. I know the Sun should blast like a furnace.

Thanks for everybody who tried to explain to or reason with me, unfortunately most of your words were like throwing pearls at swine.

Theres a lot on this page about the multi meter learn at your own pace

you will have some problem as your multi meter is an old analog Digital read out is easier (lcd screen)

sirgallivant, your multimeter is one of better ones / mirror in the scale for precise reading /
Not suitable for current you wont to measure. / max. current range is 0.25 A / only.

Nothing wrong with an old analog, you wont suffer false positives that can be a problem with digital in a damp environment like engine rooms. I just bought another one as a back up to my other digital units.

Just stick to the DCv 50 for now. Work out what part of the scale you should be looking at and practice on a few items. Car battery, torch battery etc. Print out the voltage sheet above for ready reference or find a more comprehensive one online. Just have a fiddle.

so Sir Vigillant, if you want an observers summary, your multimeter hasn't got the capacity to read how much energy if being put back into the batteries from the solar panel. If you prefer not to buy another one, then you'll be only looking at how much voltage the batteries have got left in them.

Your meter will read this for you, the red and black leads are in the correct spot, turn the dial to 50 on the lhs (DC volts), then black lead to black, red to red on the battery, and you'll get a reading of how charged the battery is. Do it for either battery, and out of interest, use you battery selector in your main panel to do the same thing, select the battery on the isolation, and choose battery test, either for one or 2. It sounds like your familiar with this.

From Charriots chart, you will get an idea of how much juice is theoretically left in each battery.

Maybe then run your radio for 1/2 hour when the solar panel is doing its stuff, test it again, and see how much it goes down, or if the panel keeps up.
To me, this is the usable thing to know, how much 'capacity' you have before your batteries are flat.

One tip for later, if you did end up getting a multimeter later on $15 ebay digital pocket one is fine, most have a 'buzzer' setting that measures continuity.
It can be useful for finding out if a simple switch is buggered, or where a break in a cable may be, and once you've got he hang of it, it's good to know.

Having boats means you end up being a plumber, electrician, rigger, painter, meteorologist etc. to some degree in the end whether you wanted to or not

so, It's perfectly logical to monitor the current from solar...not just measure..monitor constantly
this how we do it
go to Jaycar ask them for current panel meter range 15 A / check the current of solars

pick the one ...you like, would like to install to your boat
does not matter if analog or digital....only matters the one you like
after you complete this step we tell you final step

This is a BEP (NZ) marine version that basically does what you were trying to measure, showing the input the solar panel is giving to the house battery.

I purchased a larger switchboard with one built in from BEP when I rewired the boat, they can monitor more than one battery, but it does start to get a little complicated, as you need to add separate shunts like in Crusoes message above.

Thanks guys!
After listening and contemplating, l decided to invest in a controller with digital display, a new voltmeter and an offer of a beer or three to everyone who helped me to come to my senses. Sail no. 4851
The panel seems to be working, my volt meter is showing increasing voltage slowly going up from 12.4v, now 12.9v.
The temperature at the panel is like the ambient temp. around. No heating up.
At the controller is much warmer but just like a cuppa you forgot for five minutes. I can keep it in my hand, no worries but it is definitely warm, so it is working without overheating.



Only have to figure out what to buy as l am thinking to use my old 40w panel as well.
Thanks again. A lot!

why not use your old 40 watter

Read it again hg02, that is what l am planning. To use the forty watter as well.
I just have to figure out how?

How did you go with the engine? What was the problem?

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sirgallivant said..
Read it again hg02, that is what l am planning. To use the forty watter as well.
I just have to figure out how?

How did you go with the engine? What was the problem?

I wrote it wrong sorry
Engines OK Ill still give the cooling system dam good clean out though and start tidying up the fuel system gage hoses priming pump filters etc

Select to expand quote

sirgallivant said..
Dooh...
You guys are very helpful, no doubt, but you are trying to help a guy who is not even breeched as far as electronics are concerned. I have to google everything you mentioned. mppt? ldc? watts volts? It is all Chinese to me.

Ramona, I know, the supplier sent me best quality musty strand tinned wire. So that is done.

I got the message about the possible inefficiency of the regulator. I was thinking about getting a new one which displays the charging rate so l do not have to measure it, being on permanent display.

I got a four way battery switch ( see pic! ), and a three way flick-switch,so l can check the state of the batteries ( two110 amphr house and one 100 amphr starter, all newish agm's, the two house batteries lying on their sides. Would not fit otherwise.).
The two house bats are always around 14 volts while the starter n e v e r gets above 13 v. Different brands they are, thou.



LC, if l could tell negative from positive ( :o) ), I would. That is beyond me.

Datawiz, I got most of your explanation, thanks.

Riffraff, got most of it googled too.

Libran, chariot, I am still gasping but busily googeling what does not get across.

I am grateful for the helping comments, that l did or did not understand them is not you fault.
Though l am maintaining my yacht, the electronics throw me way, way out of my comfort zone.

A beer for everyone!

I'm pretty sure that phone in South Aces new boat if you ring it The lady above takes your beer order