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By michelvh
I'm developing a display to demo energy to produce power to operate several devices chosen one at a time by holding down a video game button and turning a hand cranked generator
The point being that it requires more energy to turn the generator the more power is needed.
So my devices will be something like a 2w LED, Cell phone charging (if I can do it safely) a 10w incandescent bulb and a 15w fan.
I think I may need to use 1 or more Variable load kits to enhance the difference.
The VLK will do that for me, right?
The generator will probably be 20w
Also will the VLK retain it's settings if it is powered off and back on.
Thanks for your help
User avatar
By TS-Chris
Hi Mike.

The variable load kit can provide up to 15 watts of load and you might be able to push it up to 20 watts for a brief amount of time. The VLK also doesn't remember any of it's settings when turned off and on again so it might not be what you're looking for if you're trying to simulate a load for your generator.

Other than using LEDs, fans and light bulbs for loads, you might consider using some power resistors like the 10 watt ones we carry in our power resistor kit. By adding those in various series or parallel circuits, you could create your own variable loads at a lot lower price than using multiple VLKs. Resistors don't do anything to show they are working other than get warm. If you could get various sized light bulbs and have a switch to select which ones you turn on, that would also provide a variable load with the added benefit of lighting up giving the user some visual feedback that something was happening.

It's a lot less expensive to go the low tech route and it would still get the point across that more load makes it harder to turn the crank on your generator.