High current motor controller question

I need to control one brushed DC motor. i have an Arduino Uno and i need to be able to control them forward/reverse i will only need to mess with speed control during initial set up. The motor im using that gives me the correct RPM and torque that i need is here, http://www.ebay.com/itm/350W-24-V-DC-electric-motor-f-bicycle-bike-gokart-scooter-MY1016z3-gear-reducti-/151561546871

i have been looking into high current motor controllers and have found this one on Pololu, https://www.pololu.com/product/1381

the motor pulls a max of 18.7a and this motor controller supplies a maximum of 25a continuous. I am brand new to arduino but i from with what i come up with this controler will work. i am just here to verify with you all that i am correct and that it will work with my arduino uno. i also will be running a DRV8825 stepper motor controller from the arduino at the same time and i want to make sure these two will not interfere with eachother. I appologize about these low level questions im still learning, i just want to double check with you all before i burn up my motor or my arduino and cost myself alot of money. THANKS any and all comments and suggestions help

Also what is the main difference between motor controller and motor driver, i know the motor drivers encompass the H bridge design but im curious as to which one would be best for different situations. I bring this up because i found a motor driver that will supply more than the necessary amperage than is required by the motor and it is about half the price of the motor controller. Here is the motor driver i found.

https://www.pololu.com/product/1451

IF this will work for my application i would like to use it since its so much cheaper im just curious of the pros and cons of the two different types of boards. THANKS

On the presumption that you intend powering your motor from 24 volts, you need to read the caveat that neither product is recommended, by the manufacturer, for use with a 24volt supply.

Also be aware that applying full system voltage on your intended motor will draw much more than the rated 18 amps so you either have to ensure controlled acceleration or use a unit rated for higher power, say 36+ amps with short duration overload capability. Running any control system at 100% of its rating is not good practice.

ok this is where i am confused then. i dont need to run this motor at full capacity i need it to run around 2000 rpm. which should give me more torque in return??. i understand it will have a slight over draw when it first starts moving the load. perhaps im in over my head but i do plan on supplying the motor with 24v however the driver allows me to control motor speed so by dialing down the speed would lower voltage going to the motor right??? this is where i am unsure... if i am wrong what driver board do you suggest i should use?? im stuck ive looked all over to try and find a motor that has enough torque while still producing the right amount of RPMs to do what i want. ive even tried tweeking my design to work with different motors but to no avail. i need a minimum of 5 in lbs of torque so im shooting for 10 in lbs or 11.5 kg cm to lift the load and somewhere around 1800-2000 RPMs to lift in in the time frame i need. if you know of a motor and suitable driver that would work with this application any information would be greatly appreciated.

In short i am attempting to lift a 40 pound load 28" in 10 or so seconds using a make shift lead screw design.

i thought of just running the motor with 2 SPDT relays and adjust the speed via gear ratio but i thought using a driver to control the speed might be a little easier... Let me know what you think of this idea or have any thoughts on what i should do. THANKS!!!

That motor will pull perhaps 150A at stall, you need a driver that can handle that peak rating (or whatever the battery can produce if that's smaller).

18A is the running current, not the stall current (which is what flows when you apply 24V to the motor when stationary). When the motor is running most of the supply is balancing out the backEMF due to the rotor spinning, only a small amount is left for the IR loss in the windings. Measure those windings and you'll find the resistance is perhaps 0.2 ohms or less.

You are much more likely to find a motor running at 3600rpm and 0.6Nm of torque than one at 1800rpm with 1.2Nm of torque. These midsized motors typically max out at 3600 rpm (which is when bearing wear and heating and air resistance start to eat into efficiency). The volume of a motor is proportional to the torque developed roughly, so high torque motors are big and unwieldy and a gear or toothed belt reduction gearing system is normally used to match motor to load.

since you have a lead screw you have the freedom to choose the screw pitch which is a form of gear reduction.

Ok thank you for the input thanks to your help I feel I have a pretty good foundation to start from im sure I will have more questions but I appreciate all the help!!