Bench PS Problem (Volteq HY3010D)

[eccerr0r]

Re: Bench PS Problem (Volteq HY3010D)

In RP1, RP2, RP6, and RP4 - there should be a connection between the middle pin and one of the side pins when in circuit. However RP5 and RP7 should not -- that is, if the schematic is accurate.

[orientalsniper]

Re: Bench PS Problem (Volteq HY3010D)

mmmm what should my next step be? do they sell these boards?

[eccerr0r]

Re: Bench PS Problem (Volteq HY3010D)

Can you take a better picture of the board/pots and annotate which wire goes where? Each of the voltage and current settings have three pots apparently - fine, coarse, and calibration PCB pot...

When out of circuit do RP5 and RP7 change resistance as described when rotated?

[orientalsniper]

Re: Bench PS Problem (Volteq HY3010D)

I attached photo with the pots locations circled.

RP7 resistance test failed, pin1 with pin3 resistance is way too small for the sum of 1-2 + 2-3.

It's the potentiometer then?

EDIT: What's the part number for these pots? I want to order from Digikey.

[kaboom]

Re: Bench PS Problem (Volteq HY3010D)

RP7 resistance test failed, pin1 with pin3 resistance is way too small for the sum of 1-2 + 2-3.

Because you're checking them in ckt. Pull em and try again.

[orientalsniper]

Re: Bench PS Problem (Volteq HY3010D)

ckt = circuit?

The test was done outside of circuit (soldered out). Forgot to mention that.

[kaboom]

Re: Bench PS Problem (Volteq HY3010D)

ckt = circuit?

yes

The test was done outside of circuit (soldered out). Forgot to mention that.

Ok. Try putting each wiper in the center of its rotation. Then check from 1-wiper and 3-wiper. Each should measure 1/2 of what 1-3 reads.

ASSuming linear taper, a 10k nominal should be ~5k in each half-element/wiper check. All pots have some end resistance, don't expect zero ohms from end-to-wiper when fully turned to one side.

And don't buy cheap/fake stuff from aliexpress. Mouser/Digikey are a better value overall, especially when you consider wasted time for "repeats."

You can pull the 324 and disable the tap changer. You'll then be at the lowest range of raw DC before the regulator.

Check the opamp supplies, with respect to the positive output terminal (black meter lead on + output).:

M1/M2, 4(-6.2v) & 8(+12v)
M3, 4(+12v) & 11(-15v)

[eccerr0r]

Re: Bench PS Problem (Volteq HY3010D)

Oh cool, did not realize V16 was an LED on the front panel... I assume V15 is the other LED though it's obscured by the wire. Are these LEDs lit at any time? I also wonder if they're still good too...

[eccerr0r]

Re: Bench PS Problem (Volteq HY3010D)

BTW, in order for the voltage to drop to zero or something that's usable by typical digital electronics, V16 needs to be lit. If neither LED will ever turn on, that's another data point that will help tremendously to debug this problem, all without an external voltmeter...

The only thing to make sure is that either the LED lights up, or is not open circuit in both directions.

But the data given about the potentiometers is really messed up. Please carefully remeasure and make sure there's nothing in parallel that will skew the results. Potentiometers do not fail shorted, they fail open.