| Author |
Message |
Keith Wylde
Unregistered guest
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| Posted on Wednesday, August 22, 2007 - 2:43 pm: |
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Hi, i am looking for a suitable push button motor controller for a 12v childs sit and ride car that is powered by a 12v 30ah Golf cart battery,with two small geared motors driving the rear wheels, please could you tell me if you have anything suitable or if not where i may possibly obtain such, thanks in advance, Keith Wylde |
Admin (Admin)
Board Administrator
Username: Admin
Post Number: 565
Registered: 10-2004
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| Posted on Thursday, August 23, 2007 - 10:36 am: |
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Keith,
I guess this is type where the motors speed up / slow down as you press the buttons. This type is not something that we do but are certainly used in motorised golf caddies. It could be worth trying local golf shops to see if they could help. |
Weldingartisan (Weldingartisan)
Member
Username: Weldingartisan
Post Number: 1
Registered: 3-2007
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| Posted on Monday, October 29, 2007 - 4:49 pm: |
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Hi Paul,
I purchased a Skysport4 and 4QD Vortex 75 with a DMR-203 interface from you a few months back. I now have another motor on the same robot which does not require speed control - just forward reverse. Can you supply another suitable controller/interface please.12volt 8amp full load 20amp stall. Thanks, Jeff |
Admin (Admin)
Board Administrator
Username: Admin
Post Number: 613
Registered: 10-2004
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| Posted on Tuesday, October 30, 2007 - 9:46 pm: |
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Hi,
Hopefully you will spot this as you did not leave an Email address.
Quickest way here is to use one of our Electronize RC relays with two automotive type relays. Check out part numbers 3400-010 & 1600-001 using teh fast search on our website.
This will allow forwards and reverse control of the motor but I do suggest using some fusing as well which is also available from our site. If you need help in the wiring up, do let us know. |
Steveuk11 (Steveuk11)
Member
Username: Steveuk11
Post Number: 1
Registered: 11-2007
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| Posted on Wednesday, November 28, 2007 - 12:14 pm: |
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Hi
I have a two wire linear actuator 12 volt 5 amp
I would like to control the forward and backward movement as well as it's speed. Ideally programmed from a computer, but in normal operation not being required to be connected to a computer.
Can you help, if so I would be grateful if you would provide me with a kit list.
Many thanks
Steve |
Admin (Admin)
Board Administrator
Username: Admin
Post Number: 637
Registered: 10-2004
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| Posted on Wednesday, November 28, 2007 - 8:42 pm: |
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Hi Steve,
Hopefully you spot this as you did not leave an Email address.
We will have a number of speed controllers that will be suitable but before making a recommendation, can you advise how the actuator will be controlled when not connected to a computer. Will you be using a pot or a switch or both, radio control etc.
Regards
Paul |
Steve Reed (Steveuk11)
Member
Username: Steveuk11
Post Number: 2
Registered: 11-2007
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| Posted on Friday, November 30, 2007 - 12:45 pm: |
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Hi Paul
I was thinking of just using some sort of pot attached to the actuator to provide feedback on the distance travelled, the controller or whatever then deciding when to reverse direction and speed dictated by the program.
Hope this makes sense, I'm not really that techie |
Admin (Admin)
Board Administrator
Username: Admin
Post Number: 640
Registered: 10-2004
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| Posted on Friday, November 30, 2007 - 3:11 pm: |
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Steve,
Thnak you for registering on the forum, certainly helps us to provide technical support.
Ah! this is slightly different now. What you are after is a controller that works in closed loop control. This means that the input signal from where ever it may originate, sets the desired position and the controller then runs the motorised actuator until this position is reached (as detected by the feedback pot).
Take a look at the SMC04 from Pololu search for our part number 1503-006. You can use it with a data input which could come from a computer or a pot input.
There are otherways of doing it as well, especially if you could accept a constant speed but the Pololu controller referred to above should do the job nicely. Post here if you need any further assistance.
Regards
Paul |
James Comfort
Unregistered guest
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| Posted on Friday, December 7, 2007 - 1:22 pm: |
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Could you please advise me on a motor controller for the 24V 250W Geared 9.778:1 MY1016Z2 motor (Part No: 1471-100)? I require four of these motors to drive a 20kg 4WD vehicle. The maximum accleration of the vehicle need not exceed 4m/s^2 and the maximum speed will be about 4m/s. Thanks for your time,
James |
Admin (Admin)
Board Administrator
Username: Admin
Post Number: 645
Registered: 10-2004
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| Posted on Monday, December 10, 2007 - 7:32 pm: |
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James,
I'll assume you plan to run two motors in parallel on each side. Your vehicle is very light compared to the motors so maximum torque and thus motor current will be when turning on the spot and this depends on the layout of the wheels. Our Dimension Engineering Sabertooth Dual 25A controller is borderline especially with that rather quick acceleration. However, you should not damage the controller, you may just find the current limit kicks in and slows down the acceleration.
Two of the 4QD Vortex 24V 35A controllers will easily be fine with a suitable interface. |
Mike Prince
Unregistered guest
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| Posted on Tuesday, January 8, 2008 - 2:52 pm: |
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Hi
I visited your shop today in Southampton and spoke to a nice lady, who unfortunately couldn't help me.
I am currently building a small scale landrover for my two young boys.(here is a link to some pictures if you are interested)
http://forum.rushowners.co.uk/phpBB2/viewtopic.php?t=2520
The vehicle will weigh approx 100kgs and will be driven via two 370watt 24volt electric motors. These motors have an integral gearbox with a reduction ratio of 25 to 1 and they are fixed directly to the drive wheels at the rear (one for each side). i have calculated that if i run them directly without a speed controller then with the size of tyres I have the vehicle will do 8 mph. This is a little too fast for my 4 year old and I would like to purchase a speed controller to regulate the top speed. It needs to be able to handle the motors mentioned above without going bang, and this is where your expertise comes in. What speed controller would you recommend? I would like it to have reverse protection and half speed reverse sounds good. i would also like to be to make the accelerator work properly i.e. the harder you press it the faster it goes, so i would be looking for some sort of switch which could link to the speed controller to do this. I have looked at the 4QD website which explains most things but when i contacted them direct about their speed controllers they were not a lot of help, saying that i needed to choose which speed controller i wanted.
So to sum up my problem, i need a reliable speed controller that can do forward, reverse, take an input for an accelerator, that can control two 24 volt 370 watt motors.
Can you help
Thanks Mike |
Admin (Admin)
Board Administrator
Username: Admin
Post Number: 659
Registered: 10-2004
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| Posted on Tuesday, January 8, 2008 - 8:15 pm: |
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Hi Mike,
I tend to be out and about quite often so technical issues best addressed via this forum.
Halving the speed via a speed controller (or running at 12V rather than 24V) is not a problem but you should appreciate that as a consequence, you will only have 1/4 of the motor power. This may well make your landrover under powered. Two solutions come to mind to compensate for this, the use of an additional 2:1 reduction between the motors and drive axles or to put the speed controllers into closed loop control. This will effectively make the speed controllers true speed controllers rather than a power controller. To achieve this, you need to add two small dc motors ideally to the motor spindles rather than the gearbox output shaft. This dc motors are used to generate a voltage (tacho feedback) that is proportional to motor speed. This is then compared to the signal from the throttle and enough power is applied to achieve the desired speed. makes for a very torquey drive system. If you need help with this, do let us know.
As for a controller, that's actually quite simple but if you do decide to have the tacho feedback option, we would need to know at the time of ordering.
I assume you wish to run both motors from the same controller (motors in parallel), this means about 31A max current draw (less if you decide to limit the speed to 4mph). The VTX 40 which has a 35A rating would be fine. You will need a 24V model unless deciding to reduce motor speed by running from a 12V battery rather than 24V when you would need a 12V model. The VTX offers half speed reverse, you can adjust acceleration and deceleration times, and the throttle would give you fine control over motor speed.
Hope that helps and do post again if you need further assistance.
Regards
Paul |
robert archibald
Unregistered guest
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| Posted on Wednesday, January 9, 2008 - 4:41 pm: |
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I am currently building an electric bicycle and have bought a 24v 200w motor (MY1016) from you for it.
I am now looking for a control unit for this motor, which can produce variable speeds, but will also recharge the battery when the bike is coasting.
I also need a lever or variable switch for this that will be mounted on the handlebars.
Please can you let me know if you have any products that would be suitable for this.
Regards
Robert Archibald |
Admin (Admin)
Board Administrator
Username: Admin
Post Number: 663
Registered: 10-2004
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| Posted on Wednesday, January 9, 2008 - 8:23 pm: |
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Robert,
Check out the 4QD site for throttle controls such as http://4qd.co.uk/accs/pots.html#lever We can supply these at the 4QD price as a special order.
You need a speed controller that has regen breaking to recharge the battery when slowing down. This is only offered by 4QD and Dimension Engineering controllers. For your application I would recommend the Dimension Syren 25 see http://www.technobots.co.uk/acatalog/Online_Catalogue_Dimension_Engineering_Cont rollers_34.html
Regards
Paul |
Quadra (Quadra)
Member
Username: Quadra
Post Number: 1
Registered: 1-2008
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| Posted on Wednesday, January 9, 2008 - 7:13 pm: |
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Hi Paul
Thanks for the help, firstly i must say that electronics is not my thing so i need simple solutions. Your solution to halve the speed via two dc motors sounds interesting, but i do not have the space around the motors to install this system without some major surgery to the main chassis.
What i would like to do is run the speed controller that you have suggested via a throttle plunger pot, if i used 24 volt then at full deflection the top speed would still be 8 mph, but if I restricted the travel of the accelerator pedal (and therefore the throttle pot) to half deflection then I am assuming that I would get half the speed. This is the bit i am unsure of, if I do this would the motor be producing full power for the given speed or only quarter power like you mentioned earlier.
As my boys grow i expect that I will be able to raise the speed limit to its maximum (although top speed is not the real aim here).
The other option I have is to use 12 volts which would halve the top speed, but would this have an impact on the current drawn? 12 volts is easier in some ways as it only requires one battery so the cost is lower. What would you suggest 12 volts unlimited top speed (4mph) or 24 volts with limited throttle pot travel to regulate top speed.
Sorry for all the questions.
Mike |
Admin (Admin)
Board Administrator
Username: Admin
Post Number: 664
Registered: 10-2004
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| Posted on Wednesday, January 9, 2008 - 8:35 pm: |
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Re post 659 above.
Mike,
Running the speed controller at half throttle will mean 1/4 power. This frequently causes confusion, a 370W motor at 24V will draw approx half the current of a 370W motor at 12V. Running a 24V motor at 12V could draw half the current it would at 24V. However, less power means the motor could struggle and thus run closer to its stall current and thus less efficiently.
The ideal solution remains to use a 24V supply, limit the throttle stroke but use the tacho feedback. That way you can get full power even at half speed when the car is under heavy load such as a steep climb yet it still will not race away when the load returns to normal.
The driver will find that even at low speed, the car could climb kerbs without flooring the throttle.
No problem asking questions, we are very happy to help via the forum as it means we answer away from the normally hectic day and provides a good source of information for other builders.
Regards
Paul |
Mike prince (Quadra)
Member
Username: Quadra
Post Number: 2
Registered: 1-2008
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| Posted on Wednesday, January 9, 2008 - 9:10 pm: |
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Paul
Ok so I am sold on the small motor to use as a tacho feedback. How big does this motor need to be and how would you normally attach it to the main shaft in the motor, do I need two small motors for both large motors? If I go down this route I am going to need some help with the wiring.
Cheers Mike |
Admin (Admin)
Board Administrator
Username: Admin
Post Number: 665
Registered: 10-2004
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| Posted on Thursday, January 10, 2008 - 6:59 am: |
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Mike,
The motor can be very small such as our small dc model motors. We can sort that out later once we know if it is possible to attach the tacho motor direct to your main motor shaft. I have used this method personally and I actually drilled the main motor shaft with a 2mm hole and using a grub screw simply attached the tacho motor this way. How you achieve it depends on your main motors, if you can, take a pic and attach it to your next post.
Also, check out http://4qd.co.uk/accs/tacho.html
Regards
Paul |
Mike prince (Quadra)
Member
Username: Quadra
Post Number: 3
Registered: 1-2008
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| Posted on Thursday, January 10, 2008 - 4:58 pm: |
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Paul,
On closer inspection I think I have space to fit a small motor as a tacho output on the end of the main motor shaft. This is how one of the main motors sits in the car.
[IMG]http://i5.photobucket.com/albums/y156/DaxQuadra/DaxRush015-1.jpg[/IMG]
The end of the main motor shaft protrudes from the body of the motor and is 8mm in diameter. It also has a 2mm hole drilled down the middle of it, which is approx 4mm deep. See photo below.
[IMG]http://i5.photobucket.com/albums/y156/DaxQuadra/DaxRush018.jpg[/IMG]
What do you think, a small motor with a 2mm shaft would be ideal.
Cheers Mike
P.s. Sorry I don't know how to paste pictures into the forum. |
Admin (Admin)
Board Administrator
Username: Admin
Post Number: 666
Registered: 10-2004
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| Posted on Thursday, January 10, 2008 - 6:47 pm: |
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Hi Mike,
To paste images to the forum click on the "Upload Attachment" button next to the "Preview/Post Message" button.
It does look quite promising to add the tacho feedback. What is the RPM of your motor and what distance do you have available between the motor end and bulkhead? |
