Does it matter where you put the switch on a circuit?
Electron flow stops no matter which side the switch is put on. There is often a lot more going on in the negative side of a DC system. The negative side of the DC system is often grounded for safety purposes. You do not really want to break that connection…
Where is the best place to include a switch on a DC powered circuit board?
Determine where you would like to put the switch. The most common place to put it is directly between the power supply and the item being powered. Find the positive wire—most likely red—going from the power supply to the item.
Where do you connect a switch positive or negative?
If your system has the battery negative tied to earth/safety ground (or frame ground of a vehicle), then you want the switch in the positive leg. If your battery bank is floating (not tied to any sort of safety/frame ground), in theory, you want a double pole switch that turns off both + and – power at the same time.
Why is it safer to place a switch on the positive side of..?
If “circuit ground” is tied to the actual ground, something which happens to be resting on the ground may form a closed loop. This is common in “mains” electricity (i.e. the wall outlets), so if SW1 is closed, Joe is having a bad day. SW2 doesn’t matter, and it doesn’t matter if V1 is positive or negative.
What’s the difference between high and low side switches?
The low-side switch is switching ground while the high-side switch is connecting the voltage supply. Generally in a circuit, you want to keep the ground connected and switch the power. One reason is that even when the transistor is fully turned on, there is still a small voltage drop across it.
Where does a power switch go in a negative ground circuit?
This covers AC power and positive ground circuits as well as negative ground. The circuit works the same no matter where you put the switch. Part of the electrical code (for house wiring) says that the switch should always go between the hot conductor and the load.
What happens when voltage drop across load is not relavant?
Voltage dropped across the load is not relavant. Voltage drop across the switch will increase from zero to supply whenever the switch is opened. There’s no difference if one side of the switch goes from +12 to GND or if the other side of the switch goes from GND to +12. If you want a smaller spark, use silver plated contacts.