Modification of a laboratory power supply.

To begin with, I bought a WEP 1502 power supply a long time ago. At first, I couldn’t stop raving about this device, but then, as I worked with it, I realized there were some things that didn’t suit me. There are two of them: first, the voltage and current range is too small, and there’s no current stabilization mode — only trigger protection, which sometimes got on my nerves. I didn’t want to buy a new one — why hoard money? — so I decided to modify the current one. There are many schemes for modifying it, but I decided to simply replace the modules with those that have the required parameters, and we already have the housing. So, without much thought, I take the casing apart, remove the internal components, and take out the light filter. I forgot to mention that for the assembly I used a voltmeter and an ammeter — these are two different indicators. There are combined ones, but I wanted two separate ones with large digits. Next, you will need a module — an AC/DC converter, a 36V 7A power supply; there is no model number, but you can search using this name. You will also need a control module. For this purpose, I used the XL4016 step‑down DC‑DC converter with voltage and current regulation, Max 9A, 300 W, 5–40 V to 1.2–25 V. It has both voltage and current regulation, as well as a diode with a signal indicating the transition to current‑stabilization mode. And to power the ammeter and voltmeter, I used a separate module — the LM2596S step‑down DC‑DC converter. The first problem was the size of the AC/DC board — it was quite large. Therefore, I decided to mount it vertically. To do this, I designed two supports that hold the board in a vertical position. I attached the remaining boards to the stands. I removed the trim pots from the adjustment board and installed variable resistors of 10K and 1K. The 1K resistor is mounted on the side terminal of the 10K resistance, which allows for precise adjustment of both voltage and current. To mount the ammeter and voltmeter, I designed an adapter frame, which I glued to the housing using superglue. The indicators were secured with hot‑melt adhesive from the inside. Along the way, after assessing the appearance, I decided to update the knobs as well, since the old ones didn’t look very good. We print 4 knobs and fix them to the resistors. In the center of the unit, there was a hole for the CDMA/GSM button; to cover it, I decided to place an LED there — I took it from the converter’s circuit board. Now there’s an indicator showing when the current stabilization mode is activated. I also made a round black holder so that it wouldn’t stand out from the overall theme. As a result, we get an updated power supply with a wide voltage range and a current stabilization mode up to 7 A (the AC/DC converter delivers 7 A).