Digital Readout on old Power Supply

[Quinn000]

Hello there,

Please excuse me if I have made any mistake in posting here, I am looking for some quick help.
I recently acquired an old instek PR-1810H Laboratory DC power supply. I know nothing about it, and am looking for answers. Is this a good supply? Will it work for hobby projects? Is it worth anything? Is there a manual online?

I searched for info, but came up with nothing.

I also thought, as a cool project, that there must be a way to retrofit it with two digital readouts. Currently there are two analog readouts, both with very simple two pin connecting plugs in the back. The pins lead to a potentiometer (I assume for calibration) and then directly to the gauges. The voltage meter receives anywhere from 0-14VDC.
Is there a simple digital circuit, or panel, or premade item, that I can replace these with? The only thing I see on the meters is "Type DE-680 Class 2.5"

Yes I have opened the casing, yes I am comfortable modifying potentially lethal electrical equipment. I would very much appreciate guidance over lectures.

Any help would be greatly appreciated,

-Quinn

 

[(*steve*)]

There are a number of digital voltmeter modules available. In general, you connect them up to power and the voltage you want to measure and that's about it.

You do need to be careful about the isolation between the power supply for the meter and the sense inputs, but a common ground should keep you safe (even though it's not required in many cases). You also might require an additional low power voltage regulator to supply the device with the correct voltage it requires if you can't tap it off from within the power supply.

 

[Quinn000]

Thanks for the reply,
You're saying just solder some leads to the screw connectors? Isn't that going to affect the actual output vs displayed voltage?
What about current? How do I measure that reading? There isn't a way to use the two wires that were specifically for readout? I like the idea, but there's got to be a better way.

How does a normal Digital Display PSU work?

 

[(*steve*)]

Thanks for the reply,
You're saying just solder some leads to the screw connectors?

Yep, pretty much.

Isn't that going to affect the actual output vs displayed voltage?

No, measuring the voltage as close as possible to the load will give you a more (not less) accurate answer.

What about current? How do I measure that reading?

Current is harder. Typically you measure the voltage drop across a low value resistor.

There isn't a way to use the two wires that were specifically for readout?

I have no idea. I don't know what they are connected.

I like the idea, but there's got to be a better way.

I'm not forcing you to follow my advice. I'm just telling you how it's normally done.

How does a normal Digital Display PSU work?

Pretty much exactly how I described it except it is designed into the system so it looks neater.

 

[Quinn000]

I appreciate the blow-by-blow answers, thank you.
Is there a voltage-drop-across-resistor gauge or circuit?