Okay another stupid question??? I have just brought tx and rx shrinkwrapped battery packs for my radio. I also purchased a charger which has a hitec plug which plugs straight into the hitec plug on the rx batterys and a jack which plugs into the side of my transmitter and charges the tx batterys.
There are two red lights to indicate that the batterys are charging but what I want to know is how will I now when the batterys are fully charged. I thought the light might change to green but I have had them on charge for four hours now and the light is still red. Or am I being a tad hasty perhaps and need to wait longer before they are fully charged.

Thanks,

Troy.

Depends on the charger and the Mah of the batteries. If you have the standard charger that plugs into the wall (looks similar to a telephone power supply) it takes 12 to 16 hours to charge a new or depleted pack.

THE LIGHT DOESN"T CHANGE

Yep thats the one Steve. So how will I know when they are charged? Can they be overcharged or will it stop automatically.

Thanks,

Troy.

It does not stop automatically. It is a trickle or slow charger, so it can't do much harm IMO. Just let them charge for 14 hours. You need a loaded voltmeter to accurately check the charge state of the batteries.

Have you been to Red's battery clinic site?

http://www.rcbatteryclinic.com

you'll need to get a better charger and or esv meter to read your load to get that information,lots of calculations but not knowing the start load the math will not work,at the field ever so often I'll test the batteries with the esv meter.

I had the same concerns as you when I started and I got so many words of advice I was dizzy. I bought an Accu-Cycle for $69 on sale at Tower Hobbies and it has been a lifesaver. I can charge a rcvr battery (in or out of the airplane) and a transmitter battery (in only) at the same time. It charges for 15 hours at 50 MAH and then goes to trickle (green charge light blinks at trickle). It is nice for a dummy like me. You can also charge NiMH battery's if you use them. Good clear instructions and user friendly. You can also discharge and cycle your batteres also. You can't do that with the transmitter battery on most transmitters since they install a diode to prevent external discharge. What I did was install a Futuba male and female connector in-line so I could remove the battery every few weeks to cycle it.

Oaky so unless I spend a heap of money on top of what I already have for batterys and a charger to buy an esv meter, I will have no idea when my batterys are charged. What about when I go flying but only fly for an hour or two, do I then charge my batterys for another 14 hours or so? I suppose without a meter I will have no idea? Is there any other way around this?

Regards,

Troy.

Hi troyp,disconnect the fuel gauge in your auto,get the message?I'm always in awe that one of the most important items for r/c ,which is the batteries,that few people want to spent any money on. Engine guits,fuel runs out then deadstick and land,batteries go down then crash and pick up the pieces.

I also said these words a year ago when I started. I charged 12 hours and flew 4 or 5 flights at a time. One day I noticed my plane seemed to be hit with "interference" so I landed. Luckily I was right at the runway. I had very slow response and it seemed intermittent. I discovered at rollout that I had no more control, but luckily it froze at idle as I turned on the ground. My battery was dead. It went from seeming fine to DOA in about 1 minute. Turns out that is how they die! Scary, huh? I bought a battery testing ESV for less than $20 and check my batteries before every flight. Cheap insurance- spend the $18 bucks. You can buy those little on plane battery meters for about the same which may be more convenient for checking between flights, (though you will likely buy the meter later anyway). If my plane had been racing toward the pits wide open when the battery died that cute story could have been a horror story. I later lost a plane from a battery wire breaking in flight, and it was terrible watching it fly past the pits and over the parking area over people's heads under no control. I must have seemed quite mad to the bystanders, running after it screaming at the top of my lungs, "I don't have it! Lookout!" At least that time I knew I had done everything possible to be safe...
Spend the $18!!! (Or borrow one before every flight!)
Tom

A good "cheap" solution is an onboard voltage monitor!

They come in several different guises and are easy to install. Typically there is a row of LEDs green , yellow and red - you wiggle the sticks (ie put a load on the battery pack) and watch the LEDs - if you are in the green go fly !!

The down side is that they do not look very nice on a model and have to be installed where you can see them - but IMO worth having. I have seen some that have the LED monitor built into the on/off switch, which is OK if your switch is visible !

You can also buy a voltmeter from Hitec or similar that plugs into your charge socket and loads your battery to give a reading so you can check your rx battery between each flight. These will also help when you are charging but are not the most elegant solutions!

Get a good charger with an automatic cutoff - in the long run it is the best solution because it takes all the guess work and calculations out of the process and will save your model.

I saw one (battery monitor) in a easy sport that was just the little inch long row of lights on the circuit board installed like an instrument panel in the cockpit. Easy to see and looks okay. I don't know what brand it was, he said he just took the case off.
Tom

quote from onrecess:

I bought a battery testing ESV for less than $20 and check my batteries before every flight. Cheap insurance- spend the $18 bucks.

Great advice ...

I use the Volt Watch type indicator to test my battery between each flight. However I load it down with a 20 ohm resister because this indicator uses only the servo loads you have in the plane. Not enough in my opinion. You can get them under 10 bucks now. I have info on my site to explain how to do this if anyone is interested. The bottom line is to test your battery before every flight. (even the first flight that you think you have a fully charged battery)
Ace

That's funny you say first flight, Ace. That is where I saw the display panel in the Easy Sport. A guy at Markham was going to be sharing my freq Sunday, but his little dash light showed red- EVEN THOUGH he KNEW IT WAS CHARGED!!!! I had just bought a field peak charger (which is also why I now know my pack was NEVER fully charged...) and he charged up in 15 minutes and we shared the channel, (is that nice or stupid )
Point is he KNEW it had charged for 12 hours... Oops! That light, even without additional load, saved his plane.
Tom

Quote:
That light, even without additional load, saved his plane.
Tom

Yes Tom in this case where the battery is really dead the indicator worked just fine but normally the battery starts out with a full charge (hopefully) and drains as you fly the plane. Nicads have an abrupt decay an the end of their useful charge. Without a healthy load (300-500ma) these on board indicators may give you the ok signal to fly and then the battery dies shortly after take off. I don't trust any indicator unless I know what the load is when the reading is taken. You also need to learn each battery pack. Each pack will decay differently even though they have the same capacity. If you use an indicator relics you will see what I mean.
Ace

This is why you move the sticks as I suggested in my earlier post - gets all the servos working and puts a load on the batteries - as I said before if the lights stay green (on mine) go fly!!!

Well youve all certainly made me think twice about my batterys. I will go out and get an esv meter and will also purchase a onboard meter as well.

Thanks,

Troy.

I sure know, Acebird. I said in the earlier post how my batt once died on me in flight. It worked fine and in much less than a minute it would not do anything! It just sat and circled (luckily at idle) and the servos would not move at all. The time span from a noticable drop in response to none was seconds. Then I saw articles showing the curve...almost level then- thud- right to nothing! That is why I got a field charger, cause I probably say no go when there are several flights left in the pack. I see the ESV get down to the bottom half of the range between go/no go and I stop. Of course, now that I have a quick field peak charger I am looking foreward to finding the exact flight time and capacity monitoring... even knowing when packs are too tired to keep.
I think your idea of loading the monitor is great. I know when I was new I read on a forum to buy a ESV with a load instead of using my Fluke, or to put a load on the batts.
Happy flying!
Tom

Right now your pack is probably new or relatively new so you are safe. However, as time goes on and the cells start to short themselves out little by little, you may get burned.

Most standard servos draw about 20ma when they operate so 4 will draw 80ma which is better than nothing. But testing with an 80ma load may only last 3 minutes if you are near that ragged edge. I just don't what you to have a false sense of security.

IMO on board indicators by themselves are asking for trouble. Once the plan is in the air you can't see them so they are useless. Using the same thing with a resistor that you add to the circuit via a switch can be used for every plane you own and it is more foolproof. Mind you nothing is foolproof.

Ace

My tx had to be charged a full 24 hrs initially, its only a 600ma

Acebird

Most on board monitors have a "safe/not so safe/don't fly" range of indication. I fail to see how adding a resistor would improve on this !!

My monitors have about 12 leds which, are divided into green, yellow and red sets! As mentioned before - twice - if I am in the green I fly. Any flier who adopts this practice should never get anywhere near the critical voltage drop off point!

Once you know your plane you get to know what duration your cells are good for and will also notice a drop off in duration. When it happens you know that it is time to replace the pack. (but I am anal and I log all my flights).

Always stick in the safe / green zone (or of you are really desperate for that last flight the safe/not so safe borderline is also OK).

I should have added that the monitor is not a substitute for good battery maintenence - my charger has a computer interface and I cycle my cells every 3 to 4 months and retain the graphical outputs for reference. However a lot of people do not have access to this type of gear!

What a lot of beginners do not realise is that there is a certain amount of discipline required in the hobby - eg good battery maintence and monitoring, safety , airworthiness checks on the aircraft etc etc - it is really not a plug and play hobby.

I have to ask you if you feel testing a nicad by voltage reading without a load is the same as with a load. Try this: let your battery drain down until the last green light is lite. Then put a 20 OHM resister across the red and black lead while the tester is still connected. Caution: we are talking the receiver battery only 4.8V nom. It is apt to draw it right down into the red. Load makes a huge difference.
You can check other sources but to me checking the battery with a sizable load is more important than all the electronic charging / cycling gear on the market. They are not foolproof! If you use this type of gear you darn well better be checking before the first flight.
Ace

Won't your indicator read a low green reading with a (actually)dead battery? I thought that was why we buy loaded voltmeters because a dead battery can read normal voltage at low or no load?? I know in rc cars you can be fooled by a dead pack that can pull a small load for a second or two, (like wiggling the sticks??), but move the car about 6 inches. I have put in a battery and "tested it" by seeing it steered...
If you put in a load and switched it just before each flight (to give an equivilent reading to a loaded ESV, wouldn't that be better?
Caveat reader: I am far from an expert! Very, very far... This can be considered much less than my 2 cents worth!
Tom

No Tom,
You don't need to be an expert. You understand Nicads as they perform in another hobby. They perform the same in airplanes.
Ace

Troy
Don't get lost in the shuffle get a ESV most crashes a caused by low or bad batteries. It is hard to watch a flyaway and not be able to do anything about it with the only thing left is what you have in your hand.