Adjustable DC Power Supply (0-30 V 0-10 A) with Output Enable/Disable Button HANMATEK HM310 Mini Variable Switching Digital Bench Power Supply with USB Charging

Great tool for my workbench!
First of all, I am not a techie when it comes to electrical testing. I do very, very basic stuff so this unit has been fine for my needs so far. I bought this unit for two purposes:1. To do low voltage electrolytic rust removal. I have not tested the unit in that regard yet as I don’t have my tank set up, but I have an old 1940s Craftsman bandsaw that I am restoring. I intend to remove the old paint and rust using electrolysis, so I’ll report back on that with my results once I’m finished. Based on the fact that I used to use an old car battery charger without any sort of precise control over the current, I’d imagine that this unit will be light years better for the job as long as I don’t exceed the amperage rating.2. I do a lot of automotive work, including upfitting emergency lights, sirens, etc. This unit is perfect for bench testing lights prior to install! Many new LED surface mount lights can be synced together, and flash patterns changed via applying either 12v+ or 12v- to the pattern wire. This unit makes it an absolute breeze to lay out your light heads, apply power, select the flash pattern you want and get the lights ready for install. I also was able to bench test the HID ballasts on some old TYRI lights that came off of a Cat bulldozer. This isn’t usually an easy task for me because most heavy equipment runs 24v electrical systems, which I wasn’t set up for before now. No problem with this power supply though – I just dialed in 24v, hooked up the lights and away we went. Both fired right up.I really like the fact that the on/off switch is on the front face of the unit (no fumbling with clunky switches on the back), with a separate output control button. This means you can power it up to set your current, but the leads aren’t hot until you turn the output on. This makes it a breeze to change current settings on the fly without any risk to your equipment. Overall I think this was money very well spent. I’ll update the review with any issues but I’m a happy camper for the time being.

Works good to charge Prius NiMH batteries. Be careful! If volts drop a lot, amps can melt leads.
This worked good to charge NiMH 8 volt battery modules for a Prius (one or two at a time). However I noticed that regardless if the unit is on or off, regardless if the power button is on or off, when I connect the leads to the battery I see a little spark, and there is always current flow (so be careful).The power supply worked great for about 6 hours. I kept the power button on when I connected to the battery, because it appeared that there was less of a spark.However, the last time I tried this, there was a big spark, and the leads got so hot, they melted. The voltage dropped down to almost nothing and the amps increased a LOT. I changed the leads out with a set of my own, and the unit would show very low voltage and excessive amps repeatedly (it was broke).My guess is that if I opened the unit, discharged the capacitors and replaced the fuse, this may fix the problem, but I didn’t want to take a chance, so I returned the unit. I you have a power supply that does not work, and you’re past the return window, you may try this.I received a new power supply and am happy with it so far. However going forward, I am going to be very careful when connecting the power supply to a battery. Also, I have noticed that even when the power supply is turned off, that current still flows from the battery to the power supply, so I make sure that if I am not charging the battery, it is fully disconnected from the power supply.Recommended steps to charge a Prius NiMH battery module.1) With the power supply on, but disconnected from a battery, set to 8 volts and 2.0 amps.2) It is safest to charge just one 8 volt module at a time. You can charge two 8 volt batteries at 16 volts, however you run the risk of overcharging one of the batteries.3) Turn on the power to the power supply and ensure the power button is in the off position. Connect the power supply to the to batteries ensuring the plus is connected to plus and the minus to the minus. Click the power button on.4) The charging starts either at CV (constant voltage of 8.0 volts) or CC (constant current 2.0A) depending on how close the battery is to the target voltage.5) Click the power button to turn off the charging and immediately disconnect the connection to the battery.I provided a video showing both CV (constant voltage) and CC (constant current) modes, which happen automatically based on the condition of the battery.I have the impression, this unit can be used to charge NiMH batteries to a set voltage, and the amps decrease as the battery approaches the target voltage.

Arrived a day early, I was looking for a power supply power electronic projects & testing circuits.This little power supply will do the job just fine.It looks to be made well, the innards are different from what the add shows not that it matters it’s still made very well.I powered up a 24 volt gearhead motor that pulls 8.5 amps, it handled that with no problem.I’m planning on getting another one that outputs higher voltages for use on higher voltage projects.

En general el funcionamiento es bueno hasta el momento. Muy bueno para el principiante en la electronica y practicas de circuitos digitales.

Nice little power supply. The way that the dials lock themselves out (you have to push them once to enable a change –this allows you to make fine adjustments then push it again to move each decimal place. After a couple seconds of inactivity it stops flashing and engages at the new value. Makes accidental changes less likely. Nice display and easy to read and the value appears to be quite good for others in the same category.