Hey,
I need help with some basic electronics. I’ve bought two linear actuators (that needs a 12v battery). I want to control these with a Gadgeteer board.
Now, I previously tried to control these with this x16 relay board. But it got fried when the battery was connected (too much voltage I presume?):
https://www.ghielectronics.com/catalog/product/391
The battery is 12V 20Ah for development. The battery for use “out in the field” is 110 Ah.
I realize that the relay was a bad idea, and that I probably better off with a motor driver, like this:
https://www.ghielectronics.com/catalog/product/315
Dev guide says: “A battery can be safely used to power the input on the gadgeteer power module (a red module, like USB Client DP) AND ALSO power the motors, by wiring the battery to both.”
Other stuff must be made switchable (like 12v lights and other 12v stuff that’s typically on boats) with this (presumably safer) relay:
Relay x1: https://www.ghielectronics.com/docs/188/relay-x1-module
Dev guide says: “This module may be connected to high voltages or high levels of electrical current”
My question is: can I safely connect my battery to these modules? Or do I need some kind of voltage stabilization? I really don’t want to try and fail more… it would be like flushing money down the toilet 
For info’s sake, these are the actuators from http://www.progressiveautomations.com/
Mini Linear Actuator (Stroke Size 3", Force 150 Lbs, Speed 0.59"/sec, 12 VDC) Item #PA-14-3-150-UD
Tubular High-Speed Linear Actuator (Stroke Size 12", Force 33 lbs, Speed 3.15"/sec) Item #PA-15-12-33
and they work just fine when connected directly to the battery 