@audiotubes: Seems like it's cheaper in croatia: https://www.chipoteka.hr/alati/izvori-i-napajanja/laboratorijski-izvor-2x32v-2x5a-5v-udp3305s-uni-trend-9150044680.
Disclaimer: I have never bought from that shop so I wouldn't know if it's real or a scam...
Okay, now i see, S version have on all channel ADC 16bit (ADS1118IDGSR) and 16bit DAC (DAC8562), S-E version have ADC 16bit (ADS1118IDGSR) and 14bit DAC (DAC8162).
Okay, now i see, S version have on all channel ADC 16bit (ADS1118IDGSR) and 16bit DAC (DAC8562), S-E version have ADC 16bit (ADS1118IDGSR) and 14bit DAC (DAC8162).
Il try order DAC8562, after place new ic it need calibration.. but im try it.
Hey iAleks! one question: could you please repeat the test made by thephil regarding channel power raising? I'm a little worried about those oscilloscope shots. I'm talking about the section "On/Off behaviour" on his blog [...]
@thephil: Thanks a lot for your review! I'm worried about the channel rising waveform, could be an escenario where this has to be a problem?
I own a UDP3305S, and I'm having difficulty understanding how the Over Current Protection (OCP) function operates on this device. My unit is running software version 1.10 and bootloader 1.04.
The Power Supply does not allow setting the OCP lower than the Current; it can only be set higher or equal. On channel 1, when I set it to 1A, it shifts into Constant Current (CC) mode when I draw more than 1A but does not activate the OCP. However, the OCP is triggered when I set it to 0.999A or 0.993A. This is likely a rounding error. And it never ever wants to switch channel off when OCP is set higher than current.
I can't understand why it doesn’t allow the OCP value to be set lower than the current? Am I misunderstanding how OCP should work?
Okay. Like someone said before: in Chipoteka web shop from Croatia this E model cost 390 EUR which is very good price
As far as I know, OCP is constant current modes big brother: When the OCP threshold is met, the PSU will turn off the output in certain time – think fancy fuse. So if you have set a current limit it makes no sense to set the OCP limit lower than that, because OCP would shut off the output before CC can even kick in.
Mine rises voltage in exactly same manner, it is correlated with relays switching, and I don't think that it will ever be a problem for home lab.
I have oscope and current probe, so I can take few measurements of voltage and current rise if You want to.
Totally understandable, but as You can see on photo attached in my previous post - my psu is set to 0.9A OCP and 0.9A current and it is running in CC without tripping OCP. But if I were able to set OCP lower that current I bet that it would shut down output instead going into CC mode.
I think that I should be able to set OCP lower that current output, it works this way in any other power supply that I have/had contact with. Implementation can be different (when which action happens).
What use case has setting OCP above current limit? When it will trip output?
Hi,
Yes, I got the following url for downloading the firmware image (v1.10) https://25628395.fs1.hubspotusercontent-eu1.net/hubfs/25628395/Instrument%20%20FIRMWARE/UDP3305S%20Update.rar. I don't know if/how long the link will last. As described in my blog post(http://techbotch.org/blog/lab-power-supply/index_en.htm), the update worked fine on my UDP3305S. I have no Idea if the same image is also valid for the UDP3305S-E or if that would brick the device.
- Unpack the *.rar file to get the firmware image UDP3305S.bin.
- Put the image into the root folder of a FAT32 formatted usb thumb drive. Do not change the filename.
- Turn off the power supply.
- Insert the usb drive into the usb port on the back of the power supply.
- Press and hold the UTILITY button and turn on the instrument.
- Now the update process starts.
- Once the update has finished turn the supply off and on again.
- Done.