No I dont think it totally necessary i usually test with just a multimeter. but to test each cell of a battery you will need one
You might if you want to obtain balance, check the amps, volts, and watts, but I use this - not as a buzzer, but to check the overall and individual cell voltage: http://www.amazon.com/Integy-C23212-Voltage-Checker-Warning/dp/B003Y6E6IE/ref=pd_bxgy_t_img_y Video here:
I just snagged this deal at Amazon (through one of their merchants). $9.99 for two of them (one with buzzer and one without). I have a quadcopter with no telemetry, so the buzzer and readout is going to be useful (especially if I can dangle it in front of my FPV camera!). I know the MK electronics are very useful, but this does read out every cell, and for the cost of a Bud Light at a SF 49ers' game, you can't go wrong. http://www.amazon.com/gp/product/B0081Y6QC8/ref=oh_details_o01_s00_i02
Are the two voltage readers with buzzers different? and I was reading reviews about the one without a buzzer and it reads below like .10 or something... not sure makes much different but could change something.
I ordered two sets. Extra, and two buzzers one for copter and one for wireless ground station monitor batteries.
I ordered two sets too. Delivered today. Nice little units and they come with a blue Velcro strap. Not quite sure what the deal with the blue Velcro strap is, but, I'm sure I'll figure that out.... Andy.
I got mine in the mail today. I was wondering if you could help me verify my answers. I have a 3s 11.1v 30c battery When it is fully charged each cell should approximately be around 4.2? Then total 4.2*3 Storage voltage should be around 3.8 per cell? And say I'm flying with battery what should I set the low voltage on per cell so I won't ruin the battery etc? What is the lowest voltage per cell I should go?
Hi Alex: Fully charged: 4.2v per cell. Fully discharged: 3.0 volts (but don't push it -- you'll only shorten the life of the battery! Aim for 3.3v in normal use) Storage voltage: 3.85v (your 3.8v is good). Here's a good tutorial, but there are many others if you do a Google search for lipo battery tutorialI have my low voltage warning set (for a 4S flight battery) at 14.4 -- that's a bit higher than it needs to be but I don't like the "screaming approach" kind of landing -- it tends to upset the Directory of Photography I'm working with and I can only fake the "oh, that's a normal landing" line so many times.... Thus 14.4 gives me time to say, "OK, we're coming home now," flip on Come Home until the bird is fairly close, then disable Come Home, orient, and fly a manual approach with a brief hover before touch down. Do get some Lipo bags for charging/storage though. And regard LiPo's as consumables. Andy.
Thanks Andy. Where's a good place to purchase them and how many recommend? I will have 10 8000 mah quadropower and 4-5 smaller batteries Also another question. How can I tell if a battery has damaged cells? Aka bad battery
I'd buy two medium sized bags per the 8000 mAH batteries (you can charge a pair in the bag and you can store and transport a pair in the bag). This looks like a pretty good deal: http://www.amazon.com/Bluecell-Batt...UTF8&qid=1354660109&sr=8-21&keywords=lipo+bag You can get three or four of the smaller batteries in the medium bag. Remember the bag isn't going to prevent a fire -- it will only confine the flames -- the smoke and gasses are still going to pour out through the top of the bag, but, the hope is that nothing else will catch fire. You'll need a Class D fire extinguisher to put out a lithium fire and they're spendy. Do a Google search and you'll see what I mean! You'll know you have a damaged cell if: 1. One cell will not hold it's charge (voltage will be low and it discharges sooner than others). 2. One cell will not accept a charge (voltage may be lower than others or, apparently it might charge up sooner? Seems odd...) 3. One cell will catch fire. Don't trust LiPos. Don't leave the room with LiPo's charging especially if they're not in a bag.... Dispose of the LiPo if it starts to puff up or get warm during charging. Just think of it this way: any phrase that you can use to describe a LiPo can, quite reasonably be terminated with "but there is a risk of the LiPo catching fire." Eg, If you overcharge a Lipo, if you drop..., if you damage..., if you look at it sideways...., if you .... This is, of course, exaggerating for conversational effect, but at least it will keep you safe! Andy.