Please forgive my ignorance - I am not an electronics enthusiast and I know almost nothing about solid state electronics, so I hope any answer I get will not be too full of jargon; I just want to know which product will best suit my purpose and if I absolutely need any additional equipment to use it. Also, this is my first time on this forum.
Today I ordered from Core Electronics: (1) this 5v electromagnet, (SKU: ADA3872), (220 mA, 2.5 Kg holding force). However, to suspend a load from it, I would need a lightweight hook or eye bolt with a flat, circular, ferrous base, with the hook positioned such that when a load is hung on it, the centre of gravity will be at the centre of the base, whose diameter should be similar to that of the electromagnet. (A magnetic hook is not appropriate for this purpose because you do not put a permanent magnet in close proximity to an electromagnet.)
The order is due to be shipped tomorrow (Wednesday) afternoon, and I’d like to know what the difference is between product (2) and (3) so that I can vary the order before it is dispatched if it turns out that (3) would better suit my purpose, which is described here.
Whichever one I end up using, I am proposing to power it by hooking it up to this 600 mA, switchable power-supply from Jaycar, which has a 5v setting. I need the elecromagnet to be on the whole time (possibly for 16 hours), supporting the load, until the circuit is broken by the switch, at which time the load should fall. If I use the solenoid, I will suspend the weight (about 15-20 g) by a thread looped over the rod, which would need to be extended the whole time until the circuit is broken, at which time it should retract, thus dropping the load suspended from the rod.
I also need to know if, for this very simple purpose, I can operate the electromagnet or solenoid with just that 600 mA power supply, and no additional electronics in the circuit. The website mentions a power transistor and a diode. Do I really need them, and if so, is there a ready-made (plug-n-play-style) product that I can put into the circuit?