I would like to build a simple control box to control two 12V DC fans, typical computer case type fans. I currently just connect them to a 12V Li-ion battery and use them to cool optics in a telescope. I wanted something that would allow me to control the speed and reverse the direction of the fans from a central control box, with a bonus ability to have a readout of the power applied to the fans so if I find a good speed I'd be able to approximate that setting next time around. I've been able to find most of what I need and I think I should be able to put it together in a smallish plastic enclosure that I would drill or cut holes for the connectors, knobs and displays.
My original thought was to use something like this: uniquegoods 6V 12V 24V 28V 3A 80W DC Motor Speed Controller (PWM) Speed Adjustable Reversible Switch 1203BB dc motor driver reversing to control the speed of the fans and provide the ability to reverse the direction, and then add something like this: HOT Red LED Waterproof Monitor 12 Volt Battery Meter 2.5-30V DC Auto Gauge Digital Voltmeter in the circuit after the controller to show me the voltage applied to the fans. I want control for each fan independently so I'd have one path for each fan with an output connector on the box.
NOTE: I tried to put URL's for the about italicized parts above but get an error message when I do that so I had to make them plan text.
This seemed pretty straightforward but I starting thinking and I'm not even sure that the controller I've linked will really do what I want it to do and the meter I linked won't show negative voltage so if I reverse the fans I'm pretty sure that it won't show anything or possibly damage the meter. I've looked for similar LED meters that will show positive and negative volts but every one I've found so far is either out of stock or not made anymore. I'm not married to the idea of it showing VDC, I wouldn't care if it went from 1-100, I just want some reference point that I can go back to and VDC seemed like the obvious choice.
My questions are will this work the way I think it will and is there anything else I should be considering? I obviously have no experience in circuit design so there are probably factors I'm not even aware of. Also if there is a LED display meter that will show + and - VDC I'd appreciate direction where to look, or if that will even work. So far I've just been Googling parts and there are a lot of results to sort through. I appreciate any feedback or ideas.
My original thought was to use something like this: uniquegoods 6V 12V 24V 28V 3A 80W DC Motor Speed Controller (PWM) Speed Adjustable Reversible Switch 1203BB dc motor driver reversing to control the speed of the fans and provide the ability to reverse the direction, and then add something like this: HOT Red LED Waterproof Monitor 12 Volt Battery Meter 2.5-30V DC Auto Gauge Digital Voltmeter in the circuit after the controller to show me the voltage applied to the fans. I want control for each fan independently so I'd have one path for each fan with an output connector on the box.
NOTE: I tried to put URL's for the about italicized parts above but get an error message when I do that so I had to make them plan text.
This seemed pretty straightforward but I starting thinking and I'm not even sure that the controller I've linked will really do what I want it to do and the meter I linked won't show negative voltage so if I reverse the fans I'm pretty sure that it won't show anything or possibly damage the meter. I've looked for similar LED meters that will show positive and negative volts but every one I've found so far is either out of stock or not made anymore. I'm not married to the idea of it showing VDC, I wouldn't care if it went from 1-100, I just want some reference point that I can go back to and VDC seemed like the obvious choice.
My questions are will this work the way I think it will and is there anything else I should be considering? I obviously have no experience in circuit design so there are probably factors I'm not even aware of. Also if there is a LED display meter that will show + and - VDC I'd appreciate direction where to look, or if that will even work. So far I've just been Googling parts and there are a lot of results to sort through. I appreciate any feedback or ideas.