Geoff S Posted October 12 Share Posted October 12 I've just acquired a set of electric retracts to suit the WR Hurricane I've had in 'storage' for longer than I should. They arrived promptly from Richard Wills. I've done a preliminary check using a cheap servo tester and they work perfectly. However, I'm curious about the energy consumption. I haven't gone to the trouble of attempting to measure the current (at least, yet) but I wondered if anyone else has. I'm most interested to know if they draw any current when not actually moving up or down but also how much current when they are moving. I'm sure they'll be perfectly OK for my purpose (they look to be quite sturdy) but I don't want any nasty surprises. The model will be electrically powered (6S?) and I may even use BEC with a 60 amp Frsky esc which will allow for some telemetry feedback in flight. Quote Link to comment Share on other sites More sharing options...
Allan Bennett Posted October 12 Share Posted October 12 I can't help you with the amps consumption other than to say it will vary according to the load, which will probably be mainly made up of friction in the mechanism. The one's I've used are switched off by micro switches at the ends of their travel, so consume no current when locked up or down. But they can consume a lot if they jam for some reason. For that reason I always supply them from a BEC that's separate from whatever's supplying the receiver. 1 Quote Link to comment Share on other sites More sharing options...
Simon Chaddock Posted October 12 Share Posted October 12 Retracts have fairly powerful motors and each has to "lift" a wheel simultaneously to lie flat against the wing. Sound advice to power them from a separate regulated source to the receiver to avoid a brown out during the retract after take off. 1 Quote Link to comment Share on other sites More sharing options...
Brian Cooper Posted October 13 Share Posted October 13 Current consumption will depend on the size of the retract units and how heavy the wheels are. Greatest consumption is putting the wheels up just after takeoff. Even the thrust from the propeller can put an extra strain on the wheels going up. They don't consume any current when they are at idle. . . and even if they jam during a retract cycle, they "time out" and switch themselves off, thus protecting the battery. Generally speaking, electric retracts are not too much of a strain on flight batteries, but a separate battery is good for peace of mind. 2 Quote Link to comment Share on other sites More sharing options...
Paul De Tourtoulon Posted October 13 Share Posted October 13 Even the big metal ones have silly little motors in them, but to be on the safe side maybe a fuse, or a separate nihm battery then even short-circuited it won't burst into flames, that said, mine all run ( IC ) on the receiver Nihm batteries. Quote Link to comment Share on other sites More sharing options...
Eric Robson Posted October 13 Share Posted October 13 I fly my Yak9 with electric retracts on a 4s 3600 and get up to 9 mins flight times depending on how I fly it. In strong winds or flying flat out most of the time 6 to 7 minutes is the norm. As Brian said once up no current is drawn. 1 Quote Link to comment Share on other sites More sharing options...
MattyB Posted October 13 Share Posted October 13 (edited) You don’t need to consider them in terms of reducing the flight duration as they are not on long enough to remove any significant capacity from the flight park, but running them off a separate bec or Nimh pack from the receiver is absolutely sound advice as any brown out of your RX will spoil your day. Edited October 13 by MattyB 1 Quote Link to comment Share on other sites More sharing options...
Eric Robson Posted October 13 Share Posted October 13 I do use a separate battery for retracts on my multi engine aeroplanes to try to keep the flight battery drain as even as possible. Quote Link to comment Share on other sites More sharing options...
Chris Walby Posted October 13 Share Posted October 13 If its a servoless retract it should have stall protection or as said previously they are small motors inside so should not have massive current draw (next to nothing when sitting idle). If its the old retract driven by a servo then yes if the UC jams/binds the stalled servo is going to try and achieve its commanded position until it burns out. Good practice to put UC on a separate battery if its not servoless. Just look at how many ARTF's are out there and which ones have a separate battery for the UC? Fuse is a naff idea as you are going to have to test it ..most likely to destruction to find the point when the fuse will operated when jammed, but not operate when the retract is operating under flight conditions. Fuse too small and you will probably have to land with the UC half up/down. That's why the servoless UC have stall protection that self resets on next cycle! Remember a 1A fuse does not operate at 1A ! IMO making sure that the wheels wells are large enough for the wheels + a little clearence and that nothing binds is the most best way of getting them to operate reliably. Some people cycle the UC after each landing just to make sure nothing has been bent or come loose and is likely to cause a problem on the next flight or a good visual inspection when back at the bench (with the battery isolated). 2 Quote Link to comment Share on other sites More sharing options...
Cuban8 Posted October 14 Share Posted October 14 Personally, I'd always use a separate power supply for electric retracts - servo or servoless - very little weight penalty just in case of a full short/overload somewhere in the system. You really don't want a lot of amps going through the RX PCB from its battery. Fuse is a no go......quick blow type will be difficult to specify and troublesome - slow blow/ semi delay again may not work well. Trust the electronic overload shut down that as far as I'm aware comes with all servoless retracts and in my experience works well. 1 Quote Link to comment Share on other sites More sharing options...
Albert Ace Posted October 14 Share Posted October 14 What other retracts does Richard sell, and where can I find them please ?? Albert Quote Link to comment Share on other sites More sharing options...
RICHARD WILLS Posted October 14 Share Posted October 14 Even I dont know 😬 Quote Link to comment Share on other sites More sharing options...
Ron Gray Posted October 14 Share Posted October 14 Where's Dobby when you need him? Quote Link to comment Share on other sites More sharing options...
RICHARD WILLS Posted October 14 Share Posted October 14 4 hours ago, Albert Ace said: What other retracts does Richard sell, and where can I find them please ?? Albert Pm me by all means , I may be able to help . Richard Quote Link to comment Share on other sites More sharing options...
Cuban8 Posted October 15 Share Posted October 15 https://www.aliexpress.com/w/wholesale-electric-retracts.html?spm=a2g0o.home.search.0 Worth considering - I've just started using Aliexpress and have made four smallish orders so far to try them out and found them to be fine and easy to use. Bit the bullet and ordered a Futura EDF a few weeks ago and had email this morning to say that it's now clearing UK customs - so far so good. 1 Quote Link to comment Share on other sites More sharing options...
FlyinFlynn Posted October 15 Share Posted October 15 36 minutes ago, Cuban8 said: https://www.aliexpress.com/w/wholesale-electric-retracts.html?spm=a2g0o.home.search.0 Worth considering - I've just started using Aliexpress and have made four smallish orders so far to try them out and found them to be fine and easy to use. Bit the bullet and ordered a Futura EDF a few weeks ago and had email this morning to say that it's now clearing UK customs - so far so good. I'm glad you are happy so far. You have to remember that Aliexpress is just the 'storefront' for many individual traders, many of them will be 'one man bands' operating out of their kitchen. There is always the possibility of ordering from a 'wrong 'un'. I would recommend you always take a look at what else your chosen seller is offering for sale before hitting the buy option and pick a seller which has other related offerings and not just 'trinkets'. I am something of an old hand with Aliexpress and would say, on balance, they do try and look after the buyer whenever a transaction difficulty arises but sometimes things do go wrong and sending the item back to China is a non-starter. On the larger purchases some/most traders have a local (UK or EU) address to send returns too - look for that option in the advert before buying...it is worth it! Quote Link to comment Share on other sites More sharing options...
GrumpyGnome Posted October 15 Share Posted October 15 Caveat Emptor applies.... I've bought literally hundreds of things off AE and on the one occasion I had an issie (wrong amount of items), they resolved it very efficiently. I'm a bit less convinced about 'branded' items - plenty of fakes about..... e.g. servos 1 Quote Link to comment Share on other sites More sharing options...
Cuban8 Posted October 15 Share Posted October 15 Agree...wise words indeed. Once out of the UK mail order regs and protection one is indeed taking a bit of a gamble and I accept that I might have things go pear shaped and lose my money. I've checked up on the sellers that I've used so far and their feedback has been positive and I'm very happy with the items - spending £125 on a model (Including post and tax) and saving at least £100 to £120 on the UK price is attractive and worth a punt in my book. I guess that opening a Paypal dispute to recover any losses would be the only way to recover your money - perhaps? I must say that every order so far has been fully tracked with regular updates on progress right up to delivery to my door. 1 Quote Link to comment Share on other sites More sharing options...
GrumpyGnome Posted October 15 Share Posted October 15 👍 Quote Link to comment Share on other sites More sharing options...
Albert Ace Posted October 16 Share Posted October 16 On 14/10/2024 at 17:46, RICHARD WILLS said: Even I dont know 😬 Richard. I am looking for retracts to suit a Tony Nijhuis Hurricane. Electric version, 60 inch. Sorry, don't know how to PM. Albert Quote Link to comment Share on other sites More sharing options...
Martin Harris - Moderator Posted October 16 Share Posted October 16 Click on the person’s icon (top left) i.e. to message me, click on the monkey - and then when this page appears, click on the circled message icon. …the PM form appears: Fill in subject and message then hit the send button at the bottom. Quote Link to comment Share on other sites More sharing options...
John Lee Posted October 21 Share Posted October 21 On 12/10/2024 at 21:11, Geoff S said: However, I'm curious about the energy consumption. I haven't gone to the trouble of attempting to measure the current (at least, yet) but I wondered if anyone else has. I'm most interested to know if they draw any current when not actually moving up or down but also how much current when they are moving. I'm sure they'll be perfectly OK for my purpose (they look to be quite sturdy) but I don't want any nasty surprises. I've just measured the current draw on a pair of models: 1) Freewing OV-10 Bronco weighing 3.5Kg Jeti 12 Assist Rx and digital servos. 2) E-flite T-28B Trojan weighing 1.5Kg SpektrumAR636A and analogue servos. both have manufacturers fit servos and tricycle electric retracts. The gear was cycled up and down when the model was level & static, so no slipstream or 'G' influence. The parameters were measured with a RGP SafetyMaster device fitted between the BEC & receiver. 1) 2) As you can see the peak current for the Bronco was 1.06A, with the idle current of 0.53A, so the retract cycle draws about half an amp. The Trojan had a peak current of 1.29A, with an idle current of 0.82A, so again about half an amp for the retract cycle. I then tried stalling one leg & recycled the gear. The Bronco had no measurable difference. The Trojan drew an extra half an amp for about a second before reverting to the idle current. The most surprising thing about the test for me was that the Bronco drew less power (2.7watts) than the Trojan (4watts) when static despite it having digital servos and a lighting system. 1 Quote Link to comment Share on other sites More sharing options...
Tim Flyer Posted October 21 Share Posted October 21 A very small 2s 600 to 700mah Life battery is plenty for most electric retracts . For my JP 60-120 size retracts in my 69” Mustang and most others I use the 2s 700mah Life and it’s fine and uses less than 10% capacity even after 5 or more flights Quote Link to comment Share on other sites More sharing options...
Chris Walby Posted October 21 Share Posted October 21 1 hour ago, Tim Flyer said: A very small 2s 600 to 700mah Life battery is plenty for most electric retracts . For my JP 60-120 size retracts in my 69” Mustang and most others I use the 2s 700mah Life and it’s fine and uses less than 10% capacity even after 5 or more flights Hi, Capacity is only one factor worth considering along with no load current draw. Its all well and good using a small capacity battery but there may be problems with this approach. I can't find much on the internet regarding 700 mAh Life batteries, but the general consensus seems to be that they are rated at 1C. A couple of things to bear in mind: Generally batteries with low C ratings have significant voltage roll off under high current loads e.g. when you really need all the control surfaces moving at the same time due to a dumb thumbs moment! Secondly if you have a servo bind or control surface jam then the servo stall current will be much higher than its normal operating range hence higher current draw The result of depressing the RX voltage is that the RX will "brown out" and then reboot, very possibly not what you really need in the above scenarios! 1C for a 600mAm battery is 0.6 A where as 1C for a 2000mAh battery is 2A, IMO for the additional weight I would select a larger capacity battery and one with a much higher C rating. Normal is ok, but when its abnormal its best to have as much in your back pocked as possible! Quote Link to comment Share on other sites More sharing options...
Philip Lewis 3 Posted October 21 Share Posted October 21 7 minutes ago, Chris Walby said: I can't find much on the internet regarding 700 mAh Life batteries, but the general consensus seems to be that they are rated at 1C. A couple of things to bear in mind: That's not my experience, my (very old) 700 mah LiFe packs are 5C discharge and a quick cursory look on HK seems to show that modern ones are much higher Quote Link to comment Share on other sites More sharing options...
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