Sam Taylor 1 Posted May 4, 2017 Author Share Posted May 4, 2017 Dick, that is the exact one I've got! I bought it because I needed a 6V pull action solenoid. I had no idea that it was a 'latching type' with complicated wiring. I haven't yet proved that the solenoid actually works. Connecting the pos. and neg. terminals of the battery and the solenoid does nothing, and connecting to the pos. of the battery to the neg. of the solenoid and vice versa does nothing either. I don't know very much about electronics, but I know that just connecting the solenoid to the battery won't make it work. The purpose of the solenoid is to hold back a latch. When the solenoid pulls in the latch is released, letting the glider wings fold out. Because of the radial force, I picked a solenoid rather than a linear servo. If there are pull action servos, which can withstand some radial force then this could be a suitable option. Quote Link to comment Share on other sites More sharing options...
Ace Posted May 4, 2017 Share Posted May 4, 2017 Sounds like a servo and glider tow release mechanism would fit the bill. If so maybe someone has a simple diagram. Ace Quote Link to comment Share on other sites More sharing options...
Ben B Posted May 4, 2017 Share Posted May 4, 2017 Absolutely! Quote Link to comment Share on other sites More sharing options...
Sam Taylor 1 Posted May 4, 2017 Author Share Posted May 4, 2017 thanks for the suggestions guys. My preference would be to stick with a solenoid though. If I were to buy a different type of pull action solenoid, which wasn't a latching one, could I use this with the Dr Mad Thrust Electronic On/Off switch? http://www.ebay.co.uk/itm/Dr-Mad-Thrust-Electronic-On-Off-Switch-Receiver-on-off-switch-like-Turnigy-/351738864206?hash=item51e545224e:g:eLoAAOSwPc9WuIT1 Gary, you said that to make this particular solenoid work I need to use a "relay operated by a receiver controlled switch as suggested above, with at least 2 changeover contacts to provide a polarity reversing circuit". How would I make this circuit? Would the Turnigy RX switch not do the job on its own? Edited By Sam Taylor 1 on 04/05/2017 13:15:19 Quote Link to comment Share on other sites More sharing options...
Ben B Posted May 4, 2017 Share Posted May 4, 2017 The Dr Mad Thrust switch would activate anything up to 12W so should be fine for a solenoid but as said your latching solenoid requires a relay circuit to swap the voltages. You'ld need a Dual pole dual throw switch In your installation the "motor" would be replaced by the solenoid and you would switch the battery supply to "A" using the radio switch. Quote Link to comment Share on other sites More sharing options...
Plummet Posted May 4, 2017 Share Posted May 4, 2017 What is the power consumption of the solenoid? There will probably be some markings giving the voltage and current. I think it is from RS. If so, can you give us a part number and we can look at the data sheet on the RS web site. Plummet Quote Link to comment Share on other sites More sharing options...
Sam Taylor 1 Posted May 4, 2017 Author Share Posted May 4, 2017 The solenoid I've got is 6V, 5W DC (so 0.833A). Stock code is 3002500760 http://docs-europe.electrocomponents.com/webdocs/002e/0900766b8002e8f6.pdf These are the instructions which someone posted earlier. Quote Link to comment Share on other sites More sharing options...
Dickw Posted May 4, 2017 Share Posted May 4, 2017 Posted by Ben B on 04/05/2017 13:24:47: The Dr Mad Thrust switch would activate anything up to 12W so should be fine for a solenoid but as said your latching solenoid requires a relay circuit to swap the voltages. You'ld need a Dual pole dual throw switch ...... In your installation the "motor" would be replaced by the solenoid and you would switch the battery supply to "A" using the radio switch. Unfortunately this solenoid is designed for short pulse operation only. It seems to be 5W power on 6v supply, and if I read the data sheet correctly that limits it to a max pulse length of 1 minute. It looks like Sam might need an ON/OFF momentary switch as well as polarity reversal. Dick Quote Link to comment Share on other sites More sharing options...
Dickw Posted May 4, 2017 Share Posted May 4, 2017 Posted by Sam Taylor 1 on 04/05/2017 12:34:58: Dick, that is the exact one I've got! I bought it because I needed a 6V pull action solenoid. I had no idea that it was a 'latching type' with complicated wiring. I haven't yet proved that the solenoid actually works. Connecting the pos. and neg. terminals of the battery and the solenoid does nothing, and connecting to the pos. of the battery to the neg. of the solenoid and vice versa does nothing either. I don't know very much about electronics, but I know that just connecting the solenoid to the battery won't make it work. The purpose of the solenoid is to hold back a latch. When the solenoid pulls in the latch is released, letting the glider wings fold out. Because of the radial force, I picked a solenoid rather than a linear servo. If there are pull action servos, which can withstand some radial force then this could be a suitable option. Sam It should work when connected to the battery. Red wire to battery positive and black to battery negative for a few seconds should make it move one way. Black wire to battery positive and red wire to battery negative for a few seconds should make it move the other way. If you leave it connected too long it could overheat and burn out. Dick Quote Link to comment Share on other sites More sharing options...
gangster Posted May 4, 2017 Share Posted May 4, 2017 I can see no reason why a standard servo like the Futaba 148 should not operate the latch. The throw adjustment on the transmitter can be set so that it is not hard stalled. Quote Link to comment Share on other sites More sharing options...
Gary Manuel Posted May 4, 2017 Share Posted May 4, 2017 Sam, The polarity reversing circuit I was thinking of is the one that Ben B has produced above. The receiver controlled switch would be used to switch the voltage at terminals A and B in the sketch (using a 6v supply / relay). Voltage applied to A/B would then energise the solenoid one way, and removing the voltage would energise the solenoid the other way. One problem you still have with this arrangement is that clause (ii) and Fig 1 in the instructions for your solenoid show that the 5W version has a maximum pulse duration of about 5 seconds (unclear but I think that's what it shows). This is the maximum time that you can apply either normal or reverse voltage to the solenoid for. I'm sure that it would be possible to design a pulse shaping circuit that removes the voltage after a short pulse but this is now getting a bit complex. There might also be a problem with the solenoid you have, if it is not operating by either a normal or reverse polarity supply. It should clunk / latch one way as soon as you apply a voltage, and clunk / latch the other way if you reverse it. If it's not doing this, it looks like you have a duff solenoid - maybe caused be leaving the pulse on for longer than the maximum time shown in the data sheet? A non latching solenoid driven directly from a receiver controlled switch, or the servo controlled tow release arrangement might be a better idea. Edit, some of the points I have made here have already been made in the time it took me to type it. Edited By Gary Manuel on 04/05/2017 14:48:30 Quote Link to comment Share on other sites More sharing options...
gangster Posted May 4, 2017 Share Posted May 4, 2017 I am not sure if the glider release mechanism is needed. I am assuming that Sam has already built that bit. Just needs the servo to operate it. As we have already said you will be on a hiding to nothing if the solonoid will not do anything when either polarity is applied. That needs to be sorted before anything else There is a very simple way of achieving reversed polarity which involves using an old servo . Remove the gears and the set the pot to the point where the motor stops. Remove the motor and use the leads to connect to the load. A centring stick rather than a switch would have to be used on the channel. I am not sure if this arrangement would drive a solonoid without a slave system e.g. A pair of relays or transistors Quote Link to comment Share on other sites More sharing options...
Piers Bowlan Posted May 4, 2017 Share Posted May 4, 2017 Sam, just a suggestion, how about posting a picture of your 'remote controlled glider with retracting wings', particularly the solenoid operated latch mechanism. I am sure someone on the forum can figure out a simple way of doing this that does not require a complete redesign and can be sorted quickly. +1 for using a retract servo Quote Link to comment Share on other sites More sharing options...
Peter Beeney Posted May 4, 2017 Share Posted May 4, 2017 Sam, Just a thought but usually solenoids have a mechanism to return the plunger to the off position when it’s not operated, very often a spring loaded arrangement. The version you are using would appear not to have this facility and because it’s a ‘pull in for on’ type I think it’s already in it’s operated state; and from the spec. it’s now held in this position by a permanent magnet which is cancelled by a reversed current pulse which reverses the magnetic circuit and just releases the plunger. Unfortunately, though, it doesn’t move the plunger to it’s extended open ‘off’ position, so perhaps if you lightly pull on the plunger whilst momentary giving it a short reversed current pulse you might find it will slide out. All a bit of guesswork and speculation here on my part but I’m sure you won’t do any harm by trying… if it works come back here and you might be able to use gangster’s M.O. with the servo; but with apologies to him, in a slightly different configuration. Good luck… PB Quote Link to comment Share on other sites More sharing options...
Sam Taylor 1 Posted May 4, 2017 Author Share Posted May 4, 2017 Thanks for all the help. I've got the solenoid working now when connected directly to my battery. The plunger needs to be pulled out 5-7mm and then when the pos. and neg. leads are connected to the pos. and neg. terminals of the battery, the magnet switches on and pulls the plunger in. When the power is removed the plunger doesn't just fall out. It is still held in place by the permanent magnet, but the magnetic force is low enough to be able to pull the plunger out. The solenoid doesn't actually have a spring. We didn't need to reverse the polarity or anything to get it working. When the power is off the plunger remains sucked in, but can be removed with a bit of force. Applying the power means that the plunger is firmly held in. Now that's figured out, all that remains is to be able to get it working when it's connected to my RX and TX. As there is no polarity reversal required, surely all I need is the Turnigy RX switch or the Dr Mad Thrust switch? Quote Link to comment Share on other sites More sharing options...
Denis Watkins Posted May 4, 2017 Share Posted May 4, 2017 The electronic switch will do it Sam But come to us earlier with you next project Quote Link to comment Share on other sites More sharing options...
Gary Manuel Posted May 4, 2017 Share Posted May 4, 2017 Yes Sam, the receiver controlled switch will work as long as you are happy to reset the solenoid mechanically rather than reversing the polarity and doing it electrically. May I suggest assigning the transmitter channel that operates the solenoid to a spring loaded switch? This will ensure that the solenoid only remains energised as long as you are pushing the spring loaded switch. Quote Link to comment Share on other sites More sharing options...
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