Thursday, February 16, 2017

Switching things up

Frustration was the word of the day yesterday. I guess frustration stemming from inexperience. The motor shield appeared to be in place to be usable, and it actually worked for a little bit of the time, but  that was until it all kind of went wrong.

Some of my soldering came loose on the big motor/power attachment pins, which prompted a re-solder. I'm not the one who performed the re-solder, and I have a feeling like that might have messed things up a bit. I tried hooking up the power to the shield again, and the current was quite high. The voltage was low because of the high current draw. Yeah, things did not end well... I knew that because of the large spark that was momentarily about the size of a quarter. Gah. Frustrating.

While I am able to get the Pololu shield working, it requires very careful soldering. Long story short, I am not willing to put that level of care into it at this point in time. We are going to buy a power supply and connect the motors with some switches.

Three switches will be used: one to switch on/off the x-axis, one to switch on/off the y-axis, and one as a master switch. The master switch is a DPDT center-off switch. This allows for both reverse and forward direction. The only concern is that we won't really be able to control the speed of the actuators. Maybe a rheostat could be used for that?

So yeah, that's where we are with that situation. I have wire and three switches from RadioShack. The store ended up being in a "going-out-of-business" state, so I got all three switches for around $6. Sweet!

Each switch is rated for 12 Volts and 25 Amps (or something like that). Now I just need a power supply that can give us exactly what we need. 12 Volts. From what I understand, a power supply amperage rating does not indicate that it will actually give max power all the time. If it is rated for 20A, it has the ability to supply 20A of current, but will only supply whatever amount the load requires.

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