How's this unit been working out for you? I ordered one a few days ago. Was googling for more info on it and this thread popped up.
EDIT: Not expecting it to be super precise or have low ripple, but hoping it will be good enough for testing LVP in drivers. I'm curious what the max current it will deliver at around 16v. Wondering if you have any experience with it in that regard yet.
EDIT2: Anyone aware of an OSH Park similar board to the one in this Instructible, but with a display for volts and amps?
How’s this unit been working out for you? I ordered one a few days ago. Was googling for more info on it and this thread popped up.
EDIT: Not expecting it to be super precise or have low ripple, but hoping it will be good enough for testing LVP in drivers. I’m curious what the max current it will deliver at around 16v. Wondering if you have any experience with it in that regard yet.
The bench PSU you asked about first and the product shown in that picture / link are not the same type of device. For the ATX conversion you don’t need a voltage readout: It provides 3.3, 5, and 12 volts depending on where you attach your wires. The voltage will barely move even under heavy loads. It is not CC/CV, so you cannot “set” a current (or a voltage for that matter). If you can’t set anything, there’s little reason to build in a display when your DMM can measure current or voltage (and using the same techniques that a built in display would use!).
I’m not trying to put down the ATX conversion, but you’ve got to decide what you actually want to achieve. The ATX conversion provides a stable source of a handful of set voltages and costs nothing but your time (to do a dumpster dive and then hack up the PSU).
The CC/CV PSU can be used pretty flexibly, here are some things it does that the ATX conversion does not:
charge Li-Ion batteries of any voltage using the correct profile
provide a fixed voltage with a current limit for safety (either to protect you, the equipment under test, or both)
provide a fixed current and determine Vf of an LED at different drive currents
provide a granular set voltage or current for testing purposes
I’m not trying to be pedantic, but those seem to be two totally unrelated categories of PSU to me.
Good point about voltage. Current display would still be handy though. I think someone reviewed the cheap ones at FT.
I agree about it being at different breast from the PSU I recently ordered. I'm thinking that unit (one I ordered) will be useful for most of the stuff I do, but it probably won't be able to deliver currents I would use for testing drivers/builds for heat sinking and such. At least not with lights that pull more than >10 amps from the cells. Do you see a relation to my question in the first EDIT now?
I'm just getting tired of charging cells continuously for testing stuff.
I have been using one of these and a used 19v laptop supply. I don’t know how clean the output is, I got distracted when figuring out the right way to test with my oscope. Voltage and current settings seem accurate.
Wow, thank you WarHawk-AVG. I seem to be blocked from the Dangerous Prototypes site from here. I will check that out tonight. Really like Truzzi's spin on it, but OSH Park sure gets expensive when you get beyond the size of our small drivers. Thank you again for all that awesome info. I obviously didn't search OSH Parks very well last night because I didn't see those projects.
Thank you eas. Looking for something higher current, but I will check that out to see if I want that too.
I'm using mine, but not very much. Richard pm'ed me asking for more info as well. I really can't help much - nothing to compare it with, and haven't done any higher voltage - all single LED stuff. I'm not crazy about it's reaction time - seems to delay when adjusting, so you can easily get to high amps and blow a LED - think it happened just once to me but always a concern. Not crazy bout the fine/coarse arrangement, but of course I'm not used to using anything like this. Again, can't compare it to anything and am not sure of all it's usages.
Thanks Tom E. Mine arrived yesterday and I played it it for a little bit. You're right that their seems to be a delay and one needs to pace themselve adjusting the voltage and current. It acts like it has a large output capacitor that charges up when you go up and discharges as you go down with voltage. I definitely recommend shorting the terminals to bring down the voltage when hooking up a LED that has a lower Vf than the cap is charged to. I noticed a couple unexpected surges on start up that I think were due to that.
The unit was a fine driving an MT-G2 at almost 8.3 volts and 10 amps. I didn't have another available to connect 2 in series. I'll report back once I try that. Due to the response issue you mentioned, I didn't have the guts to try a more delicate emitter.
I connected a DMM that I have had since the mid 80's. I seems to read slightly less current than the PS reports (e.g. DMM 5.7 amps, PS 5.77 amps). I was using the stock PS leads which are long and skinny. I guess that still tells me the the old DMM is probably still reasonably accurate for my crude purposes.
The new bench power supply came in handy today in an unexpected way.
Battery in my Grand Cherokee was completely flat (dome light was on and car has been sitting for a few weeks). Couldn't find my automotive battery charger anywhere. So thought this could be a good exercise for the bench PS. Hooked it up, cranked the current knobs to max and then turned on the unit. Then turned up the voltage until it hit 14 amps volts. Let it charge for a few hours and then cranked the car up.
The unit never seemed to get very hot except at the output jacks. Need to make some better leads for it. The fan is real smooth and quite. I'm starting to warm up to this PS. Just need to go slow when adjusting the knobs.
Control: front panel or via Arduino Nano using USB or RS-485
Two level of control for both current and voltage outputs: coarse and fine for ease of use
Outputs: 0-50 V and 0-20 A
Protection: over-voltage and reverse-voltage protection
Input voltage: 110V AC and 220V AC switchable
Voltage Stabilization: <=0.2%
Current Stabilization: <=0.5%
Load Regulation: <=0.3%
Ripple noise: CV <= 1%
LCD reading accuracy: +/-1% +/-1 digit
Environment: 0-40C, relative humidity < 90%
Size: 12" x 10" x 6"
Weight: 16 lbs
Warranty: 1 year
And I consider this to be the least expensive DC switching regulated from budget - features POV. No any mods needed, you can use it straight out from the box. Sadly no distributors to Indonesia.
I do not know anything about that power supply, but I do not like two knobs for setting a value. I prefer one multiturn (That can be a DIY project) or a digital encoder.
It must be fairly bad connectors on the front or thin wires inside, usual good binding post can handle 30A
Do the fan run at full speed all the time or only when needed?
The O.V. setting is a nice feature and can mean less fried stuff.
I know, I neither like two buttons control too. But still can’t find any budget DCPSU with 50+V and 15+A with less knobs and some keypads.
If it’s just the wires, should be easy to mod. FYI, the front output is auxillary, the main output is located behind the DCPSU. I’ll try to post the complete manual, still got no answer from the manufacturer.
Rigol is also nice MIC product but comes at very expensive price ranges. I like to invest in tools but not going to spend USD 2500+ for a DCPSU….at least for now
I did notice the screws at the back. Output on the back is nice for permanent test setups, but for bench usage I prefer output on the front, even my 50A supply has that.
Rigol is not expensive ($2500 is way to high for a Rigol), try checking Keithley 2280S-32-6, that supply is rather expensive and very good.
I favourite supply for most testing is TTI QL355P, I have a couple of them.
Probably, but without testing I do not really know anything.
Also be aware that it is missing remote sense, this means the voltage at the target will always be lower than the selected voltage when running high currents.
