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16 |
| The simplest of all motor controllers (besides a straight on/off switch) is the contactor controller. I designed this contactor controller for use in my electric scooter project. It is based around three 12V relays, two 12V batteries, two switches and of course a motor. Having no silicon to "fry", it is quite reliable and robust. A contactor controller works by rearranging the two (or more) supply batteries between series and parallel. This gives the motor a slow speed (batteries in parallel, current adds) and a fast speed (batteries in series, voltage adds). This assures that both batteries are discharged equally. When the circuit is "at rest", the batteries are connected in parallel, which allows easy recharging. |
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K1 is simply another of the same relay as used in the controller. S1 is another switch. R1 needs to be chosen based on your motor, but it will be of low value (under 10 Ohm) and high wattage (normally at least 100W). It must be capable of handling the full current drawn by the motor. This is not exactly an efficient way to limit current to the motor as excess current is dissipated as heat by the resistor, so it is normally only used for a "starter" speed.
Related Circuits |
Comments |
| Thank you for your time in this presentation of a simple controller, greatly appriciated, will gather thses parts and test out. | ||
| hi , dear, i need solution for make out put watts low, can it posible in my recent controller of my electric bike ? my cotroller right now is 250w for use of 48 v battery. right now i need solution of want low output watts from controller with loading one person. i hope reply me promptly. | ||
| I've been trying for the past couples of days now to build a simple 12V DC motor using FDN and PFN circuit but is not working out because anytime i apply the power; it just scooting on without any control and if their is any barrier on the way it will be put to stop instead of getting power from the feedback circuit.Is their anything i could do to make it work properly. | ||
| the cost of this circuit ?.. | ||
| hi, i need the details of the dc series motor used in motor bike (for electric bike). | ||
| can i get that of AC motors | ||
| Two graduate projects and one project "to the faculty"...wow...is there a way to chip these people so they can be tracked? I don't want to buy anything from the companies they end up working for. | ||
| Hello.. I need articles and circuit diagram with source code for "DC motor speed control using PIC microcontroller" for my graduate project.. I am waiting for your reply.. Thank you.. | ||
| Can anyone show me how to make a one speed motor into a two speed motor? I have a 7.5 HP Pool pump but i need only half the amount of horse power. 7.5 is too much. It runs on 220 Volts. Thanks | ||
| I have been hunting for a controller circuit that I can build and this is it. I have a stern wheel paddle boat I built that runs on 12vdc and so far it has been running wide open both in forward and reverse. Obviuosly this is hard on the drive train. The second circuit is what I need as I run two seperate motors. (one for each side as the paddles are split for stearing purposes along with the rudder) They draw 8-12 amps under load so the 30 amp relays are plenty enough. I will let you know how it turns out. | ||
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