Voltmeter - a must have

[ian.mich]

http://www.ebay.com/itm/170846310527?ss ... 1497.l2649

Buy this. it is amazing. I ziptie it on top of the anderson charge port for my customers. no dc converter necessary and goes to 120V. I don't even use a wattmeter anymore.

[miuan]

I use them all around. They are like a gas tank gauge as long as your tank is well balanced.

[dogman]

Yeah, I just picked up a few recently and did a thread on em. They aren't all that accurate, like for having one on each cell measuring less than 4v. But they work great for a whole pack monitor. A .1v variance is nothing on 60v. For most of us, 120v max is plenty. Just knowing you start your journey with full charged voltage is priceless.

Only trouble with em is they are hard to read in bright sunlight. That's about 355 days a year here. So you have to shadow box em somehow to read them. Wish they had a display more like the CA.

Dirt cheap, no excuse to not have a voltmeter now!

[ian.mich]

for sure, would not use em for cell monitoring lol but great as a gas gauge and thats why i strap it on top of the charge port, very helpful that its waterproof aswell. it is usually off by a .1 but doesnt matter in a full pack situation

[cal3thousand]

This thing rigged to a momentary switch built into a case would be a pretty good idea for a quick check. I wouldn't necessarily use it as a "gas gauge", but it will let me know whether this pack has been topped up or used.

I'll buy a couple... thanks for the link.

[deVries]

With free shipping at $6.53 usd its cheap.

[HypnoToad]

These look good, they're so cheap that I've just ordered 2 of them so I'll have a backup.

The one I'm using right now isn't waterproof, and needs another power source, so I've got little pp3 battery right now and a switch all mounted in a tic tac box and lots of hot glue.

This will be far cleaner and neater, thanks.

[cwah]

A voltmeter should be plugged in serie or parallel? Is there an amp limitation for a voltmeter?

[ian.mich]

yep its cheap as can be and its amazing. only ever off by .1, no dc converter necessary, waterproof! what else can you ask for. who needs a CA when you can mod a turnigy meter for Ah and use this for voltage?

[cwah]

How can you mod the turnigy wattmeter to accept more than 60V

[HypnoToad]

A voltmeter should be plugged in serie or parallel? Is there an amp limitation for a voltmeter?

Always connect a voltmeter in parallel with whatever voltage you need to measure

[cwah]

This one is a little bit more expensive but measure the current (up to 50A) and does 100V:
http://www.ebay.co.uk/itm/Red-Orange-LE ... 20c92e17b3

[miuan]

Good find! Anyone actually used one?

[deVries]

Good find! Anyone actually used one?

Dogman did a thread about these.

[Edit: wrong info.]

Use link in Cwah post above. Not sure if anyone has tried these yet either?

[ian.mich]

Good find! Anyone actually used one?

Dogman did a thread about these. See below...

Yeah, I just picked up a few recently and did a thread on em. They aren't all that accurate, like for having one on each cell measuring less than 4v. But they work great for a whole pack monitor. A .1v variance is nothing on 60v. For most of us, 120v max is plenty. Just knowing you start your journey with full charged voltage is priceless.

Only trouble with em is they are hard to read in bright sunlight.

I think he was referring to the wattmeter

[miuan]

No he was not. I ordered one of these today. PM me in one month if I forget to come back over here.

[HypnoToad]

Bear in mind the unit that measures current needs a separate power supply.

Pp3 batteries will work, but you'll need extra wiring, switch, etc.

[miuan]

I use 12V for lighting all over my bikes anyway, so I just use the 2A wall adaptor I already have... 70mA is next to nothing.
As a crude solution, we could use a 10W resistor in series to power it.

[def215]

i just got mine in the mail today. i have it on my battery bag on a switch so i can switch it on and look at it if needed:

it seems pretty accurate, within 0.01 of a volt higher than my DMM. i think its pretty good for 7 bucks.

[HypnoToad]

Looks good, if you have room it may be worth mounting it on the handlebars, as it's nice to see how much voltage sag you get up hills.

Also, when did you order yours? I ordered mine around 2 weeks ago, and it still has yet to show up. Fingers crossed it should arrive sometime next week.

[def215]

i did want to put it on my handlebars, but all of my electrics are in the bag. ill mainly use this for battery status to determine range and for charging. i just didnt want to keep my wattmeter permanently on this bike just to look at the voltage for those purposes.

i ordered mine on july 19th, and it just got here today. so a bit over 3 weeks. now im waiting for the $15 wattmeter to come in from the same seller.

[ian.mich]

i did want to put it on my handlebars, but all of my electrics are in the bag. ill mainly use this for battery status to determine range and for charging. i just didnt want to keep my wattmeter permanently on this bike just to look at the voltage for those purposes.

i ordered mine on july 19th, and it just got here today. so a bit over 3 weeks. now im waiting for the $15 wattmeter to come in from the same seller.

yeah shipping time is brutal for these things

[migueralliart]

I bought a couple of those and some plastic enclosures. My plan is to make some easy DIY handlebar install that looks CLEAN. I'll probably start a DIY thread to help others do so as well.


If only I could find a similar AMP meter with external shunt and with the same voltage range that doesn't require power. I could integrate it into the plastic enclosure and it will be perfect for any low budget build.

[teklektik]

If only I could find a similar AMP meter with external shunt and with the same voltage range that doesn't require power. I could integrate it into the plastic enclosure and it will be perfect for any low budget build.

Hmmm - this ammeter doesn't appear to require an isolated supply - appears to use a common Gnd. Maybe with a bit of zener and 12v regulator magic (similar to this) you would be in business....

[ian.mich]

sure you can get a cheap ammeter, but would you really want one? the voltmeter is fine because it carries no power, but when i'm out on the road dumping 6kw, i dont want some ten dollar chinese circuitry to go pop. go to hobbyking and get a meter with 12g wiring