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>> Home > Tags > battery voltage

battery voltage
battery life
battery mount
battery pack
battery power
battery voltage
46" Firefloat What Motor/Battery by pmdevlin Fleet Admiral!   Posted: 6 hours ago
Hi John, you might now be scratching your head, and wishing you have not asked the original question! This seems to be a common issue, as the boating community is light years behind the other disciplines, rc cars, planes helis and so on, its probably due to the facts general boating doesnt really need the later generation technology, the average boater age is probably higher than the other disciplines so budgeting might be an issue, and there is less younger blood in the clubs to explain the lipo/brushless etc. We see posts with a load of numbers, specs, warnings etc, its enough to put people off. Im a big fan of brushless/lipo/ 2.4 etc, been doing it for years, its cheaper and more efficient (once you have the basics) but for the average guy, who just wants to spend an easy afternoon at the local lake gently cruising around, brushed motors, nimhs batteries, even lead acid, will do the job👍 Your 4 foot ply boat, once painted, with fittings, will be heavy, I know, I own one. Those 600 motors are not big enough, they are better suited to the smaller 3 foot boat, then, pushing them with a 6v lead acid, just cant do it. The battery will be screaming HELP!! I started 15 years back exactly the same, 600 motor, 6v battery, massive 50mm prop, I knew no better and took advise from people who didnt know what they were talking about😡, remember those gold hi tech speed controllers!! I had one, it melted, literally melted on the first use😭 Get 700 size motors, they will need to be water cooled, as mentioned by jarvo, the nominal voltage or below isnt good enough, power them at the max voltage. Brushed means you can use one apropriate esc, look out for electronize (are they still in existance?) or mtroniks, preferably use nimhs batteries over lead acid with a high mah. If after all this you want to venture into lipos and brushless motors, go to a club, spot a boat that is similar in size to yours, if you like the performance talk to the owner and gain experience and knowledge that way, it will save money, lost time and a lot of disappointment, I have been there so feel your pain. I say I would never go back to brushed motors and none lipo batteries, but I always want silly speed, not runtime, after 15 minutes Ive had enough and am bored. Rambling over! My 4 foot boat is twin brushless and uses 4 lipo 5000mah cells per motor, it will do 25mph for 15 mins, then I go home😁 Message is, you can get a "reasonable" performance from brushed motors, with the correct batteries, right props, but weight is the enemy. Looks lie you are at Biddulph, get onto Dave M a moderator on here, and arrange to go over to see the crewe and district boys on one of their sailing days, take your boat with you, they will help👍

MV TEAKWOOD by RHBaker Fleet Admiral!   Posted: 9 days ago
Before the funnel could be installed wanted to fit a working radar scanner, navigation lights and the batteries. Decided to use sub C NIMH batteries in plastic holders, they should have the target endurance and provide some ballast. Fitted two sets of 4 cells, one at the forward end of the superstructure and the other at the rear, both at keel level. These were inserted into wooden battery trays to hold them in place. A dry test run showed a full speed motor run time well exceeding the hour target, so will try on water. Also took the opportunity to fit the Rx and then adjust the rudder before finishing off the wiring. Both the navigation lights (LEDs) and the radar scanner work. The radar is driven by a servo with the potentiometer removed and a magnetic drive shaft run up through the superstructure from below the deck. The motor requires about 9 volts to run at what would seem to be something approximating to scale speed; fitted a voltage reducer to allow the lights and the radar to work on less than 6 volts. The mast lights are to be installed in a separate circuit after the masts are added. As I get more into the detail it is evident the GA drawing and the photographs of the vessel in service differ. Fortunately the component locations seem consistent, although the equipment is not. This most apparent in the hold ventilators. The GA shows the standard cowl vents, but the photographs show a mixture between an vertically squeezed oval vent (which am advised is more typically German) and ventilator columns with cylindrical caps. The column style vents with cylindrical caps were easily made from two different sizes of styrene tube with the cap tops made from styrene offcuts. The squeezed oval style vents were more difficult. Broke them down into the major parts of the cylindrical vertical tube and, from a larger tube cut a small ring and filed one end to straddle the tube once it had been squeezed oval. Glued it into place whilst restrained in a small hand vice. Once set, removed and sanded the the two to give a smooth transition, closing the rear aperture off with styrene offcuts. Then resorted to wood filler, filed down to give a smooth, oval vent.

NimH advice by Dave M Fleet Admiral!   Posted: 2 months ago
Hi Alex They will be connected in series with the positive connected to the negative. I suggest you carefully cut off the heat shrink covering, taking care not to cut into the cells. You can then check each cells voltage. The nominal is 1.2v rising to 1.4v when charged. Any around 1v or less will never hold a charge so mark them with a marker pen. Hopefully it will be one of the end cells that has failed. On your type of pack the bottom of the battery (negative) will be in a metal case attached to the top (positive) of the next cell. I use a flat blade screwdriver to separate the cells (they are spot welded) and sometimes you can get the case off the bottom of the dud cell, leaving it attached to the positive of the next cell. I suggest you then charge the remaining good cells to see if they all take a full charge. If they are OK you can get a new cell or just make a lower voltage pack. I use a piece of stranded wire to repair the joint. You will need a 40+watt iron and some solder paste, and may need to scratch the battery case and pin for the solder to take. If you were careful with removing the heat shrink you can use it to cover the pack with a bit of electrical tape to make good. Please ask if you need any guidance with the process. I have been doing this for many years and may not have explained in enough detail if it's new to you. Do remember if the battery is charged it can short in its unwrapped state so do make sure you bench is uncluttered and kept clear of any metal objects. Good luck

46" Firefloat What Motor/Battery by canabus Admiral   Posted: 2 months ago
Hi What type of props are you using(size and number of blades). I see your basic problem is under powered motors and a very heavy battery. I made the big switch over three years ago from brush to brushless motors and to Lipo batteries. With the help on the forum and club members it was a learning curve, but, I would not go back. A 5800mah Lipo battery is in the weight of 450 to 570 grams and would give you a good 1/2 hour run time. A good balance charger and safety bag are the main requirements, also maximum charging for the 5800mah battery is 5.8 Amps(same as the old Nicads). Also a low voltage battery alarm. Your 600 motors can draw up to12Amps !!! Replacement same size motors for your mounts would be 35mm brushless motors, but, you will require two ESCs with a Y connector to run on the same throttle channel. Replacement brushless motors are far more powerful e.g. a Hobbyking 3639-1100kv with a 60Amp ESC on a 4S 5800mah Lipo Battery is 800watts and with two in your boat is 1600 watts!!! Your old motor would in the 100 watt each mark !! I have the same size crash tender, but, with a single brushless motor. I have all the order numbers for the motors etc. and a setup the ESCs if your require. Canabus

PROBOAT RECOIL 17 12.1 VOLT BATTERY by Dave M Fleet Admiral!   Posted: 2 months ago
Hi Les Yes I agree there is no way with the charger supplied you can do anything other than charge to full capacity. I do believe we have made suggestions on another thread on the site advising possible solutions. The cheapest would be to just buy a simple battery checker and make sure after you use the battery the voltage is around the 3.7-3.8v mark. Run a bit more to reduce and short charge to increase. If you are intending to become serious about modelling and using LiPos then, like most of us you will want to buy a charger that does the job for you automatically. There is a cost but if you protect your batteries they will last and save you money in the long term. I've not had much hair for some years so probably that's why!

PROBOAT RECOIL 17 12.1 VOLT BATTERY by Dave M Fleet Admiral!   Posted: 2 months ago
Hi Les It means what it says. Good to see a clearly marked battery for once. You can discharge at up to 20 times the capacity 1300x20= 26000Ma or 26amps It claims you can charge at 3 time capacity 3.9amps. Personally I never charge my Lipos at more than the rated capacity 1.3amps in your case. The battery capacity is 1300Mah has 3 cells (3S) and a nominal voltage of 11.1v (3.7v per cell) Each Lipo should be treated in accordance with its specs. A 2200mah battery may well have a different discharge rate. The dearer batteries usually have higher discharge capabilities. Charging should be done individually and again in accordance with its specs. Not sure why you are asking the final question but if you are thinking of using two batteries together they should have identical specs. Personally I would advise against this as you run the risk of damaging a battery if all the cells are not balanced, not to mention the risks involved both personal and material.

Motor problem by RichardSReade Sub-Lieutenant   Posted: 3 months ago
Reilly, I stand corrected I see what you are saying, the speed of the boat is just about right, if I fit a smaller prop then I will need a much faster motor to keep it at that speed then I presume the battery will not last as long, in fact that is something I would like to work out, although I am ok with wiring and working out loads at mains voltage etc. my ohms law is useless with DC voltage and mAh Haverlock I had a look at that motor but I see the recommended motor mount would block of the front air holes again (same mout as I have) Canabus thanks for that sounds expensive besides which I have spent out nearly, my pension does not really extend to this hobby, but enjoyment is important. I wonder if the last three words of the previous paragraph is a quote from some famous person I could add to the bottom of my posts😁

Motor problem by RichardSReade Sub-Lieutenant   Posted: 3 months ago
Scout13 I only have one battery connected at a time, with two batteries in situ I can use the other one when the first one is flagging,to give a longer running time, I could put them in Parallel but prefer to know I have a charged battery to use with an approx running time before it fails altogether. I have made a cover over the shaft coupling to prevent any cables coming into contact with it should they move, there is plenty of air space around this cover as well but the photo does not show it.Dave M the pond is weed free and the prop is the recommended one in the plans for the boat, as far as I am aware it is no larger dia. than the motor, but I will check that.As far as the weights I had to put lead in the front and mid section to get the boat down into the water as it was sitting on the hull and was not stable, I had some lead in the back as well as I used a spirit level when I was sorting it out in the bath, however when I first tried it in the pond the back end was too low in the water when it was going, so I took the heavier weight from the section just rear of the motor compartment and swapped it for the lighter weight just forward of the motor compartment, although this was better when tried again the stern was too low when it was moving so I removed the weights from the stern and as far as I could see it was just right, stationary the boat looked levelish but when moving on full throttle, the bow came up and had a nice bow wave with the stern down below the water level but with a (for want of the technical term) a hollow wave, when on a slower throttle it was fine and sailed nicely at all speed levels. What worries me is that the motor shown fitted in the boat was supposed to be the better motor than the photo of the one outside of the boat, would this benefit from a water cooled motor as to be honest I would not want to alter the top speed of the boat as it is just about right . just to let you all know I have a background knowledge of electrics so do know the difference between parallel and series voltages😊

Motor problem by Dave M Fleet Admiral!   Posted: 3 months ago
Hi Richard I suspect the prop fitted is too big for the motor. If the pond had lots of weed this will also have placed a heavy load on the motor. Ideally the prop should be a lesser diameter than the motor and preferably not too coarse a pitch. A 550 motor that you intend to fit should be fine. Do a quick run round the pond and bring into the bank to check the motor. If you can't touch without going ouch! its overloaded and you need a smaller prop. Mention has already been made about the batteries. The motor is rated at 7.2 volts so one battery is the correct voltage. If you connect two batteries in series I suspect you will see some more smoke. To help the model to come onto the plane it will help if the bulk of the ballast and weight is towards the rear. Hope this helps

Twin motor control problem by RNinMunich Fleet Admiral!   Posted: 3 months ago
Hi Dave, I'm inclined to agree, makes no sense! @ John: can you please finally confirm if you have tried a run without using any BEC? Looking at all the above with my engineer's analytical view I'm beginning to wonder if the 'at sea' load on a single source battery is causing the BEC voltage to sag which puts the RX into 'Failsafe' mode. It can't be an ESC Failsafe problem because ESC Failsafe just means All Stop! Cheers Doug 😎

DISCHARGE CONUNDRUM by Dave M Fleet Admiral!   Posted: 3 months ago
Hi Les Thank you. There are three LEDS which change from red to green when fully charged. I can see no mention of setting a half charge. Haverlock was right in thinking each cell was charged by the balance lead so you will be protected from overcharging. The solution is to buy a battery checker theirs is DYN4071 and I have one in my collection. Using the checker involves plugging the battery via the balance lead into the balancer and each cell voltage is displayed sequentially. So you charge for half your normal length of time and check the voltage of each cell is about 3.7 to 3.8v. Bit clunky but would work. A better solution would be to invest in a balancer charger which will automatically charge to full voltage or the storage charge. There are several available some with mains power supplies and others needing a DC power source. Have a look at I have a Giant Power G6AC but they all work just as well. Please ask if you need more info

Twin motor control problem by Haverlock Fleet Admiral!   Posted: 3 months ago
Your problem is interesting me one other thought is:- when the boat is out of the water the loading ( current) is way lower than the same motors in the water. It may be possible that the increased current is causing the voltage to " sag" and thus cause all sorts of strange effects. One simple thing you could try is to remove the red lead from the ESC(s) and power the receiver from its own battery. That's the red lead to the RX not the ones to the battery. If you can use a watt meter to read the battery voltage and current draw with the boat in the water.

DISCHARGE CONUNDRUM by Dave M Fleet Admiral!   Posted: 3 months ago
Hi Les Can you upload the instruction manual? The storage charge is normally set by your charger and the balance lead on the battery is used by the charger to set each cell to the storage voltage. If there is only one LED then I suspect this is after all cells have reached the set charge value. Hopefully the charger manual will help

lipo storage charge by Dave M Fleet Admiral!   Posted: 3 months ago
As I explained I was talking about charging at the end of my first post. For a novice I do believe video explanations are far easier to follow which is why I made my initial suggestion. I did not look at your first suggestion as it required me to download a pdf file from a source I do not know. The other two sites both suggest it is safe to discharge down to 2.5v per cell - may have been when written but modern cells should be kept above 3v and I try to keep mine nearer 3.5 v. I also see they recommend charging at 2C from storage! If you buy a 3 cell LiPo mine are delivered with an 11.1v storage charge which equates to 3.7v per cell. I did once watch a very long and detailed video made by a developer and manufacturer of LiPo batteries and learn't that at 3.7v the cell was in its most stable state (chemically wise) consistent with long life and storage. If the battery has any charge I do believe the amount of damage will be the same, but perhaps more spectacular if fully charged. Most modern chargers from reputable suppliers will provide a safe charging and storage charge. Providing your charger is setting the right voltages no harm should occur. As they say a video says a thousand words and the one I suggested covered the Imax B6 very comprehensibly.

lipo storage charge by RNinMunich Fleet Admiral!   Posted: 3 months ago
Hi Dave, I'm sorry too cos I didn't say you recommended anything! But you did state that 'something is wrong', which it clearly wasn't operating the unit in Storage Charge mode. Also 3.7V is only the nominal cell voltage. The recommended Storage voltage is 3.85V, as stated in the charger manual, and which is what the charger did. The objective is to limit the amount of stored energy which can cause havoc if anything unforeseen happens in storage, as well as to prolong the life of the battery. See also attached LiPo storage tips. Just three samples of several which all state the storage voltage (SV) as 3.8 or 3.85V. The safety leaflets which came with my LiPos also said the same. Cheers Doug 😎