Turnigy watt meter for $25

[liveforphysics]

It will help the motor get more juice. You know I wouldn't do something that would decrease power.

Low ESR means low Equilivant Series Resistance. These caps we add in the power wires are there to help make the voltage as solid, and as free from spikes as possible. The lower the ESR, the better they are at doing this task. It's listed on the cap's spec sheet. When picking a cap, pick something with 10-20% overhead in voltage, and as low of ESR as you can find, and you're picking the cap that will perform the best for keeping voltage stable.

 

[Hyena]

I wouldnt risk running an 18S lipo pack Kim, which is what I assume you're thinking of. I ran a 15S pack (63v off the charge) for months and it was fine, but I reckon it'll blow on 18S.
Thats what I'm currently running on my norco and I ended up just running the meter across 1 of the 6S parallel bundles. It means it basically only reads as a 6S pack, so you have to multiply your wattage by 3 to get the true value, but the current draw and amp hour values are correct - which are the main things I use it for. Current for throttle control if you're trying to get good milage from the pack and AH as a fuel gauge.

 

[liveforphysics]

Good suggestion. He could run it from just 1 or 2 groups of packs, and still get useful data.

Or, he could just buy a cycle analyist and be set to rock and roll.

 

[AussieJester]

Or, he could just buy a cycle analyist and be set to rock and roll.

I have a drain brain already Luke but i couldnt work out how to connect the 200amp shunt up

KiM

 

[liveforphysics]

We can help you get that all figured out.

 

[Doctorbass]

DocBass...how far over 70volts would you predict it would go before magical smoke appeared? Would 72v be pushing it
In your expert opinion, me needs it too work say it will Doc pleeeease say it will... :lol:

KiM

Luke is Right about ESR caps
Low ESR would help certainly, but it will just solve the voltage spikes problem in case of inductive current creating by the motor and wiring and that occur only when you disconnect or connect or switch ON or OFF the system...

But for the continuous voltage hold, Low ESR just reduce the ripple ( AC voltage) on the DC line.

If the DC (that is the average voltage of the power battery wire) is too high the Turnigy meter will not like that.

As i sayd already, the limit is the internal SOIC 8 pins regulator chip. This chip have a max of 60V according to the specs. I dont know about the max Absolute rating, but using it over the normal rating would reduce it's life and one day it will probably blow if used with overvoltage.

The way it work is that it take the 4-60V input and regulate it to around 5V or 3.3V to supply the circuit and LCD. But if you use the auxiliary input like on the Watt's up meter as the external source, you could increase the voltage of the measured input and it would work
but will also blow the regulator.

I have one that the regulator is blown ( a Watt's up meter) and i use it with the auxiliary source input. I've put up to 80V, but it just WONT display it.. .it's like the reading is programmed just up to 80V.. above that, it will still display 80V.

( PLEASE READ THE ENTIRE POST.. IF YOU READ PARTIALLY these last phrases, I DONT WANT YOU TO THINK I SAID IT WORK UP TO 80V...)

It,s the same for the Astroflight Wattmeter i have.

Doc

 

[HighTekBikes]

I still have not heard from anyone who has tested the watt hour function. I don't think it is correct. You would have to put in series with a cycle analyst (or trusted meter) and run for an hour.

 

[icecube57]

The watt hour function is dead on. The DP CA i find to be all over the place. If the leads are to long or the temps arent right it can display whatever the hell it wants. I was able to get one CA to exactly match up with my Watts UP meter down to .025Ah. Doctorbass has tested the Watts Up meter and Turnigy and found them to be almost exact within a resonable range of less than 1% accurracy. I stand by these types of meters.

On several watts up meters I had the max voltage it would display is around 68v but ive put packs on it as high as 72v. It would ready like 68.37v until the voltage dipped down low enough. It still displayed all the other information.

 

[amberwolf]

I still have not heard from anyone who has tested the watt hour function. I don't think it is correct. You would have to put in series with a cycle analyst (or trusted meter) and run for an hour.

So far, at least at currents below 5A, where I can safely measure them for long periods with my Fluke 77 III, the TWM I have here does measure Wh correctly. I will shortly be comparing it to a WU as well (donated by AussieJester). Don't have access to a CA to check.

 

[MrBoots]

Received mine yesterday, shipping took about 12 business days. Surprisingly, this thing's a little heavier/sturdier than I expected. I just hooked up it up to my RC esc and batt and it seems to work pretty well. Really glad I purchased this instead of a Watts-Up. Now let's just hope it holds up!

 

[morph999]

I don't really like my Turnigy watt meter but for $25, it's a good deal. I just wish it didn't scroll through the data and instead let us select which data we want to look at. It's too hard to ride and view it at the same time. I can't be looking down for 10 seconds to see what my used AH is. The cycle analyst is superior to the Turnigy watt meter.

 

[Hyena]

I think they're not quite as easy to read as the wattsup due to the backlight and/or the contrast of the screen is a little less. Still for the price you can't complain.
They're not supposed to be a competitor for the CA at 1/8th the price, they're basically a wattsup clone for 1/2 the price. Yeah the scrolling isnt ideal but thats a feature copied over from the WU

 

[Doctorbass]

Hey guys.. I got the schematics!!! ( of the Watts Up meter).. The Original Meter desing that was copied by Turnigy



:wink: :wink: :wink: :wink: :wink: :wink:

WATT'S UP METER SCHEMATIC

--- PDF INCLUDED ---... For those who did not seen it! :wink:

Doc

 

[Doctorbass]

Now.. Lets compare both of them

Ladies and Gentlemen, i the left corner:

The ORIGINAL Watts Up meter the favorite of the RC comunity since 4 years!

No... In the right corner,

The Copie of the Watts Up meter, Half the price and 130A, The TURNIGY WATTMETER !!

Both are very similar!!!.. and as i said.. the little 8 pins chip on the right IS WHAT LIMIT IT TO MAX 60V :wink:

I confirm.. I blown mine tinight at 100V by mistake...

Doc

 

[TMaster]

Wow they really cloned that thing! I see you bent the board pins over; I actually clipped mine.

So I learned today that it only will display up to 70.5V, Today my battery was 74.5V according to my multimeter. I gave it a tiny bit of throttle and the voltage stayed at 70.5; then gunned it and it droped down and read around 68 or so. So the output numerically has been programed to have that as its max is very dissapointing. I've acutally just modified mine to take 22V-100V. And It can do up to 150V with a cap change. Prolly around 9 hours invested in getting the prototype done, then the costs. . I'm pleased to say it works great, but unfortunately anyone using over a 72V setup would not see the current voltage till the pack was almost drained or not even at all. All the other data is fine though.
I use mine for the voltage, amp hours used, and the real time watts. Being able to see how much AH I have left is most importaint to me.
I had planned on modifying these for people, or even selling them ready to go. Of course the cost would be more, I haven't set a price yet. I need to ask my friend monday if he can program the chip inside to display a higher value, he has a programmer socket and the software, but then again the chip is soldered to the board.. I don't know which ones does the value... etc.. I don't think that will be happening.

How much would you pay for a 100V or 150V unit that would only read up to 70.5V ?
How much would you pay for a 100V or 150V unit that would read the correct value?

 

[Doctorbass]

WANT THE FAMOUS ANSWER ABOUT WHAT THE HELL IS LIMITING IT TO 60V ??

HERE IS THE ANSWER:

It's the LM2936 Voltage regulator that is rated to take an input of MAX 60V.. and as Tmaster Discovered.. it's also the source code that was programmed to 70V max reading!

The regulator is a 3.3V Ultra-Low Quiescent Current LDO Voltage Regulator.

LM2936BM3.3 in SOIC 8 format.

PDF
http://www.national.com/ds/LM/LM2936.pdf

Doc

 

[TMaster]

Yep thats the little bugger! Where would this source code be?

 

[swbluto]

Yep thats the little bugger! Where would this source code be?

Rofl. Gotta make your own.

(Or you can pay the chinese a couple of grand to extract the program from the chip, and then you can use your famous hacking skills to change the "70" value, and then reload it onto the chip.)

 

[TMaster]

and then you can use your famous hacking skills to change the "70" value,

LOL! I guess we're screwed then!

Here's the display just for Sh*ts and giggles: http://www.bluemoon-lcd.com/gb2312/pdf/C1602A.pdf

 

[FeralDog]

Turnigy is not a "clone" , it is Pirated.

 

[AussieJester]

Thankie You berry much round-eye capitalist lackey. You workie , me profitie .... Money, oh so good, me buy new Mercedes ...

And me gets to buy a meter for half the cost of the WattsUp "me berry happy too! " hope they CLONE more designs so it saves me $$$

Nice find too Doc...now work on making it work on 70v and above there's a good chap

KiM

 

[monster]

is the turnigy meter water proof ?

this is the major limitation of the watts up meter imo. i have lost two meters to the rain now.

 

[TMaster]

Nice find too Doc...now work on making it work on 70v and above there's a good chap

I've acutally just modified mine to take 22V-100V. And It can do up to 150V with a cap change

 

[AussieJester]

is the turnigy meter water proof ?

this is the major limitation of the watts up meter imo. i have lost two meters to the rain now.

Doubt their waterproof maybe water resistant though, definitely more so than a wattsup i think, the turnigy has a clear plastci screen covering the LCD screen, if it doesn't keep the rain out wouldnt be a hard ask to pop it apart and smear some silicone about the
cover to make it so...

KiM

 

[Doctorbass]

Certainly not waterproof!.. No seal gasket or silicone.. just 4 screw and 2 half case cover.

But the Wattsup meter is AT LEAST sealed by glue on both half of the case... AND MAKE IT DIFFICULT TO OPEN... ... but fesable :wink:

Doc