What does BC mean on a PCB terminal?

[robzy]

I pulled apart one of these: https://www.jaycar.com.au/compact-switchmode-laboratory-power-supply/p/MP3800

And I can't quite remember how to reconnect the 2 output terminals.

The PCB has three terminals in the same place: +, GND, and BC GND -.

Coincidentally this video by Clough 42 shows a circuitboard that also has a "BC-" terminal:

What is the BC terminal for? What does it stand for?

[DTJ]

Flip the PCB over, are the BC-GND and the other GROUND connected and connected by the same weight track?

If so it may not matter which one you connect the output ground to.

[Harry_22]

Bare Copper ?

[thm_w]

The Clough video has BC+ (red) and BC- (black).
Its likely hinted in the manual: https://kb-controls.com/content/product_pdf/KBAC%20Manual.pdf
I don't know where they go off to, something internal to the drive.

Anyway I doubt its related to the Jaycar PSU at all. BC there might be bare case, bottom case, or something.

[robzy]

Flip the PCB over, are the BC-GND and the other GROUND connected and connected by the same weight track?

If so it may not matter which one you connect the output ground to.

Annoyingly - they are not directly connected.

Electrically they are connected - according to my multimeter - but they come from different parts of the circuit.

There's spare PCB between the two terminals, so they could've been directly connected if desired.

I want to say "if they appear electrically connected then it won't make a difference" - but why would they go to all the trouble of routing them in from different places?

[Jonathon_Doran]

Battery connection?

[floobydust]

I think "BC GND-" means Bus Capacitor(-) for the VFD motor drive PCB pic shown Clough 42. That is for the primary HV bus, after the mains bridge rectifier.

What it means for the Jaycar lab power supply though must be different... the pic shows it right near the LV secondary terminals which would be very dangerous spacings if "BC GND-" goes to the primary MOSFET source after a sense resistor. You'd have to follow it back the PCB trace. It could be for EMI with C101,102,103 connecting the two grounds.

[DTJ]

Flip the PCB over, are the BC-GND and the other GROUND connected and connected by the same weight track?

If so it may not matter which one you connect the output ground to.

Electrically they are connected - according to my multimeter - but they come from different parts of the circuit.

I want to say "if they appear electrically connected then it won't make a difference" - but why would they go to all the trouble of routing them in from different places?

I've no real reason to say this but I wonder if there is current sensing in the ground return circuit and the two ground side lugs straddle the current shunt.

[robzy]

I've no real reason to say this but I wonder if there is current sensing in the ground return circuit and the two ground side lugs straddle the current shunt.

That's a really interesting theory!