Interesting SOLAR meter

[BigRAWesty]

To follow up on the rc side of things, here is a site with popular cheapish units

https://www.hobbyking.com/hobbyking/...att_Meter.html

[sooty_10]

They are good little meters provided those buying them recognise the meters’ limitations & have the understanding of how best to use them. They will tell you, depending upon where they are connected how many amps are coming in or going out .... in real time, as well as solar voltage &/or battery voltage in real time. This is useful info, but for those who want a meter to give a relatively accurate reading of a battery’s State of Charge an ammeter with a shunt is needed. The difference is that this will record amps in & amps out & with the capacity of the battery dialled in by the owner will calculate the battery’s SoC. There is no 100% accurate means of monitoring a battery because chemical reactions are affected by a number of variables, but such a monitor is the best anyone can do. However as I said, & for a lot less money, those little meters can be quite helpful once the user knows how & when to interpret the readouts with familiarity. They can also be bought far cheaper without the Anderson plugs attached. .... (Ah, I see TD has found those).

The cheapest battery monitor with a shunt that I am aware of is the one I have in my Patrol. They are available in Oz, but can be bought from the UK for less, including postage. I bought half a dozen as a group buy on another forum & got them for $140 each delivered about 18 months ago. (saved on postage & paid no VAT/GST) http://www.foxsonline.com/cgi-bin/sh...R#aNNBM1C_2dGR Not suggesting that everyone should have one, but I do think it worthwhile to counter some of the advertising I have seen, particularly aimed at unwary 4wd’ers, selling volt meters as battery monitors. (Advertisers who have no connection to any posters here I hasten to add.)

Cuppa

Ps. By coincidence I have written about the exact same thing to a forum member here via PM in the last day or two).

Just had a look at those NASA marine units on fox's and they look pretty decent. Did a quick checkout to see what it was going to cost and came in at £168.91, postage was the killer at £115.71 as without VAT they are only £53.20.

Definitely a group buy item

[sooty_10]

There is also these units which guys on the other forum have used before

http://www.ebay.com.au/itm/GT-Power-...item485cbb5d6d

Not sure myself what the differences are between these and the blue ones as I haven't delved too deep in them, just watching with interest for when I get a solar setup.

[kevin07]

Just had a look at those NASA marine units on fox's and they look pretty decent. Did a quick checkout to see what it was going to cost and came in at £168.91, postage was the killer at £115.71 as without VAT they are only £53.20.

Definitely a group buy item

my son is in England at the moment maybe something can be organised

[the evil twin]

They are good little meters provided those buying them recognise the meters’ limitations & have the understanding of how best to use them. They will tell you, depending upon where they are connected how many amps are coming in or going out .... in real time, as well as solar voltage &/or battery voltage in real time. This is useful info, but for those who want a meter to give a relatively accurate reading of a battery’s State of Charge an ammeter with a shunt is needed. The difference is that this will record amps in & amps out & with the capacity of the battery dialled in by the owner will calculate the battery’s SoC. There is no 100% accurate means of monitoring a battery because chemical reactions are affected by a number of variables, but such a monitor is the best anyone can do. However as I said, & for a lot less money, those little meters can be quite helpful once the user knows how & when to interpret the readouts with familiarity. They can also be bought far cheaper without the Anderson plugs attached. .... (Ah, I see TD has found those).

The cheapest battery monitor with a shunt that I am aware of is the one I have in my Patrol. They are available in Oz, but can be bought from the UK for less, including postage. I bought half a dozen as a group buy on another forum & got them for $140 each delivered about 18 months ago. (saved on postage & paid no VAT/GST) http://www.foxsonline.com/cgi-bin/sh...R#aNNBM1C_2dGR Not suggesting that everyone should have one, but I do think it worthwhile to counter some of the advertising I have seen, particularly aimed at unwary 4wd’ers, selling volt meters as battery monitors. (Advertisers who have no connection to any posters here I hasten to add.)

Cuppa

Ps. By coincidence I have written about the exact same thing to a forum member here via PM in the last day or two).

Agree with most of what you say there Cobber but just to clarify a few things for others who may not quite get the gist.

There are two common ways to measure DC current flow for our purposes.
Inductance Coil and Current Shunt
Current shunt is simply a voltmeter measuring voltage drop across a very low resistance in the circuit and displaying it as current flow.
When you use Current Shunts you have two options for the meter, external and internal but apart from that they work exactly the same.
External is often preferred for high current applications and allows ease of interchangeability for ranging but internal is perfectly fine for low current fixed range use

Cuppa's link is for a device using an external shunt and the $20 meters in this thread use an internal shunt and both units are of very similar accuracy etc.

Not bagging the device in Cuppa's thread at all just saying both Meters use the same measurement technology but Cuppa's has some extra "smarts" for SOC calcs.

Inductance Coil is a "donut" around the cable and the advantage of that is you don't have to cut in to the cable so there are less joints to go high resstance or cause issues. Very handy for vehicles but usually more expensive in relation to Current Shunts

[the evil twin]

To put it even more simply...

All examples in the thread so far are Current Shunt meters.
The cheaper options are marketed as a "Power Meter" the dearer is marketed as a "Battery Monitor".
The Battery Monitor has some extra algorithms in it to convert the voltage and current to determine State of Charge.
It's SOC accuracy is dependant on how close teh Battery is to the algorithms which are usually pretty good admittedly.

[threedogs]

@ $15 it might be worth buying a couple.

http://www.ebay.com.au/itm/271325488...84.m1423.l2649

[Cuppa]

Just had a look at those NASA marine units on fox's and they look pretty decent. Did a quick checkout to see what it was going to cost and came in at £168.91, postage was the killer at £115.71 as without VAT they are only £53.20.

Definitely a group buy item

Not sure where that postage figure came from but it does sound very high. I don't have my laptop with me to check what i paid in postage, but it was certainly much much lower than that for 6 units combined. I recently bought a stereo amp from the uk & when looking had some very high postage costs quoted. The place I got it from were able to send it via international courier for about Aus$60 & the parcel would have been 3 or 4 times the size of 6 battery monitors & many more times the weight. (Not only that but from payment to delivery to my front door took just 4 days!). $$115 postage is ridiculous for an item as small & light as the monitor, & i'm guessing it must have been via the Uk's Royal mail?

[threedogs]

I've just brought two for $14 each one I'll plug inline with
the camper battery the other inline with the Aux on the Patrol.
I get heaps of stuff from the UK and $115 sounds very high,
compared to USA the UK post is very reasonable IMO

[sooty_10]

Not sure where that postage figure came from but it does sound very high. I don't have my laptop with me to check what i paid in postage, but it was certainly much much lower than that for 6 units combined. I recently bought a stereo amp from the uk & when looking had some very high postage costs quoted. The place I got it from were able to send it via international courier for about Aus$60 & the parcel would have been 3 or 4 times the size of 6 battery monitors & many more times the weight. (Not only that but from payment to delivery to my front door took just 4 days!). $$115 postage is ridiculous for an item as small & light as the monitor, & i'm guessing it must have been via the Uk's Royal mail?

I got the prices direct from foxsonline.com, there was no options for postage? But agreed it seems excessive for what it is. Here is the postage info from the checkout...... Parcelforce Int Sch-Zone11 (£115.71)