Sign up or log in to customize your list. Here's how it works: Anybody can ask a question The best answers are voted up and rise to the top I'm going to build a motorized barn-door mount for astrophotography, but have ABSOLUTELY no experience with motors, circuits or anything else related to the motor. I've read about resistors, voltage, wire gauge, etc, etc... I need it at 1 rpm consistently from I turn it on until I turn it of. I plan on having a snap-switch on the thing. Now, what do I need??? I have the motor, motor mount, switch and that's it. What gauge wire do I need? One of those boards that look like they belong in a computer? I've searched in here and took a look at the videos where I bought the motor, but I'm too green in this.... Hope someone in here can help. You need just motor, switch, wire and fuse. The motor has a stall current of 0.5A. That's the most it'll ever expect to draw. So you need a fuse that'll blow at more than that (1A would be fine).
You also need wire that can take 0.5A minimum. You also need to consider how far from the battery the motor will be. Under normal operation it'll be somewhere between 95mA and 500mA (0.5A) current draw depending on the load it has to move. So we'll take the worst case of 500mA. 24AWG is the absolute thinnest wire you could get away with for 500mA. Any thinner than that and it'll fuse. 24AWG has a resistance of 25.67mΩ per foot. we can work out that, per foot at 500mA, you would drop: V = 0.02567 \times 0.5 = 12.8mV So after 10 feet of wire your 12V would be (12 - (0.0128 * 20) * 2) 11.744V. Note, it's times 20 not times 10 as you have to remember, it's "there and back again", so 10 feet distance is 10 feet of wire there, and 10 feet back again, so 20 feet of wire. But, choosing thicker wire, say 18AWG, which is about twice as thick as 24AWG, the resistance drops right down to just 6.385mΩ per foot. So for 10 feet distance (20 feet of wire) you'd be losing just 64mV, so your 12V would still be 11.94V.
You could hook it directly to the 12v battery, with the switch in between. If you want to be a little bit better, a common 1n400x diode in reverse across the motor terminals, and a slow blow 0 6 to 1 amp fuse would be nice. That motor only takes a tenth of an amp, so 22 or lower gauge wire will do. Common 2 pair lamp electrical wire will be 16 to 18 Gauge and work fine. A car battery will last for weeks on this motor alone. It probably won't move a barn door though. I need it at 1 rpm consistently from I turn it on until I turn it off The product page states (emphasis added): They have a gear ratio of 3000:1 and operate up to 12 volts and deliver a stall torque of 2995 oz-in. and a max speed of 1 RPM. Maximum speed means it might be something less. In fact, if there is any mechanical load on the motor, I can pretty much guarantee it will be less. If you don't actually need the speed to be consistent, then you can follow the advice in the other answers and hook it up to a battery.
But if you actually do need a consistent speed, this motor is probably not going to work well for you. For a consistent speed, you need something to regulate the speed. You have generally two options: Measure the speed, and adjust the drive voltage to adjust the speed towards a target speed. This is called a servo. Use a synchronous motor, one that turns at a rate synchronous with an AC driving waveform. A stepper motor is one kind, but there are others. In either case, using those devices is a little more complicated than can be explained in the scope of one answer, but now you have a direction to research. Sign up or log in Sign up using Google Sign up using Email and Password Post as a guest By posting your answer, you agree to the privacy policy and terms of service. Not the answer you're looking for? Browse other questions tagged motor wire or ask your own question. SoundStepper is a 100% software telescope controller, for Windows, that uses audio hardware to control step motors in real time.
All it requires is an external analog current amplifier to operate. SoundStepper can control up to 4 motors (RA, Dec, focuser and field derotator) of a equatorial or alt-azimuth-mounted telescope.SoundStepper can control any type of equatorial-mounted telescopes with step motors. Manual-pointing mounts (ex: barndoor, poncet platforms, "polar axis", threaded-rod driven mounts), "meridian-flip" mounts (ex: GEM or cross-axis), and "no-meridian-flip" mounts (ex: Fork, yoke, horseshoe, split-ring), and beginning from 5.0 beta version, alt-azimuth mounts too.SoundStepper can "sync" and "go-to" manual-pointing mounts, making faint objects easier to find (manually center scope on a star, find the star in Cartes du Ciel, right-button, "sync", right-button on faint object, "go-to").Using analog control, SoundStepper drive step motors with quietness, smoothness and linearity. With adjustable linearity, the typical wobbling is 1/20 of step. Like microstep controllers, it can put the motors in any position between step positions.
In addition to the analog control option, SoundStepper is also capable to control commercial "pulse/direction" microstepping drivers.No PICs, no micro soldering on small SMDs, no EPROMs. SoundStepper uses cheap USB-AUDIO devices to drive steppers, through a simple (SUGGESTED) analog current controller, or standard "pulse/direction" drivers.No MS-DOS dedicated computers. SoundStepper does realtime control sharing the computer with planetarium, photo/video capture and others applications, in Windows. It take advantage of the audio devices buffering and autonomous playing.SoundStepper has built-in PEC and NPEC (periodic and non-periodic error correction systems). With NPEC, the entire threaded rod can be "trained", enabling the use of cheap thread rods, and the "thread rod/nut/arm" system (like "Astrotrac").Main screen with keyboard arrows "control box" (four speeds: slew, find, center and guiding), go-to, flip, park/unpark, and focuser/rotator controls.Permit save many defined positions of focuser, according eyepiece, camera, barlow and filter being used.
LX200 command interface compatibility, enabling the use of LX200 ASCOM driver, through any virtual serial-TCP redirector. The TCP/IP interface enable control the scope from a remote computer. Compatible and tested with many softwares, including Cartes du Ciel and Stellarium.Configuration screen with many controls, to match SoundStepper with your motors and mount.Autosave and autorecover last telescope and motor positions (crash recover)Joystick interface: You can control the telescope with a standard joystick, wired or wireless.Field derotation for alt-azimuth mountsBacklash compensationPortable: You can run SoundStepper from any external HD or Pen-drive. No installation procedure is required.Now certified from Windows XP to Windows 10, including Vista, 7 and 8.1 versions, 32 and 64-bit I know my own opinion can't be neutral, but I have to write it here: it really works, is cheap, and easy to assembly. Thank to it, I'm rid of parallel/serial ports and MSDOS for the equivalent of US$25 per motor.
And I didn't have to weld PICs nor burn EPROMs. And the software is free, open source and public domain. No more I lose 30 minutes or more trying to find a 16th magnitude comet or asteroid in the sky! Using latest version of Soundstepper, even with my "threaded rod/arm" mount, now I can do "sync" in a nearby star, and "go-to" for an object that would be almost impossible to find otherwise. English, Portuguese, Brazilian Portuguese Non-Profit Organizations, Science/Research, Advanced End Users, Developers, End Users/Desktop Win32 (MS Windows), Console/Terminal, Windows Aero Thanks for helping keep SourceForge clean. Right-click on ad, choose "Copy Link", then paste here → (This may not be possible with some types of ads) More information about our ad policies You seem to have CSS turned off. Please don't fill out this field. Briefly describe the problem (required): Select a file, or drag & drop file here. Please provide the ad click URL, if possible: