I received a few of the SCT-006 clamp on current transformers.
they have 2 wires and I want to run a single multi conductor wire from them.
I bought some head-phone cables with the idea of cutting off one end to have a molded plug and a finished cable for my project.
since they are 3 wire and we only use two wires… could I make connect 2 units, share the reference and have each run back on one wire ?
I am using an op-amp for my reference.
my board could have each channel break out on the board with a ballast resistor.
At this time, I have 1 meter cords, and the ones I got are not shielded. I could change the wire length if that would make much difference.
Also, I could use on the same phase if that would have any effect.
as a note, This is for a 20 amp circuit in the US, 60 Hz, since our rules dictate that we do not load a circuit over 80% of it’s rating, 16 amps is the maximum that is designed or expected.
You could. Those are “proper” current sources, so the voltage drop in the common wire should make no difference, it is the current circulating in each loop that is measured and turned into a voltage by the burden resistor. So as long as you don’t have a common wire carrying current after the burden resistor, you should be OK.
At 1 m long, I’d not worry about shielding, as it’s quite low impedance.
Thanks. that means having 1/2 as many cable in the target panel and 1/2 as many places to make wrong connections. and 1/2 as many 3.5mm plugs on a board.
I just ordered some and will post some pictures once I get them wired up.
That sounds like win – win – win.
I noticed that earlier. You do things in a roundabout way over there . Here, we can use up to the maximum rating indefinitely, go above the maximum and you’re up against the I2t curves for the protection devices, so a common 32 A MCB will carry about 100 A for 20 s (somewhat temperature-dependent) before tripping.