# DC series additive voltage and component selection

#### clarky456

Joined Jul 11, 2018
3
Hey Gals and Guys, hopefully a quick question.

Attempting to put together a (spotlight) circuit using the best plug and play components the industry has to offer. I have connectors rated for 130V at 2.8 amps that I would like to utilize. My DC series circuit has 6 40 volt LEDs whose additive voltage equals 240V. Would my connectors and wiring between the resistors need to be rated for the full 240v of the complete circuit, or just the 40v of the resistor? If the connectors can be utilized, should it be assumed the maximum power of the circuit would be 364 watts (130*2.8)?

Thanks!

Joe

Joined Feb 20, 2016
3,597
It is always good practice to rate the connectors for equal or greater than the supply.

#### Electric Rhino

Joined Oct 8, 2018
7
A drawing would be super helpful.

I'd recommend getting a connector rated for what you're trying to do (you've done the calculations already). With that said though, the only risk of using a under-rated connector is that between neighboring wires in the connector, you get a breakdown of the insulator, which can cause some sparks and perhaps lead to an excessive current draw from the connector being dead.

If you're willing to accept that fact, go for it. I know I would

#### clarky456

Joined Jul 11, 2018
3
Thanks dendad and Electric Rhino. Reading through "Kirchoff's Law" (https://www.allaboutcircuits.com/textbook/direct-current/chpt-6/kirchhoffs-voltage-law-kvl/) it appears that the total circuit voltage is only available to the first resistor from the power supply. Thereafter, each resistor reduces the voltage. Electronics always have me thinking pressure/flow for volt/amp. With that thought in mind, it appears that the connection to load needs to be rated for total circuit voltage. I know of others that think otherwise, that the connector should be rated to the individual load, in this case 40v.

Sparks and excessive current adds spice to life, this project is fairly tame though. Looks like I need to shop for some new connectors!

Joe

#### MisterBill2

Joined Jan 23, 2018
6,757
If you can re-arange the circuit to have two sets of 3 LED devices in parallel then the voltage would be less and the circuit will be more reliable, since if one set opens the other will remain lighted. Of course, that would depend on the power source being able to deliver 120 volts instead of 240. Probably some mention of what you intend to use as a power source would be good. 240 volts DC can give a really nasty and hazardous shock. So that should also be a consideration.