Instek GPS-3303 vs TEKPOWER TP-3005D-3 Power supply experience? - Page 1
Forum section: electronics / testgear

author: Ecklar
author_rank: Regular Contributor
timestamp: July 01, 2015, 11:25:26 pm
content: Does any one have any experience with the GW Instek GPS-3303 power supply? Is it any good? In particular I am curious how it compares to something like the TekPower TP-3305D-3 as far as quality or accuracy or anything else that's important. I see the Instek on sale foe anywhere from $375 to $420US. The comparable TekPower is going for $185 US. Any thoughts ?Also, is the TekPower the same as Kaito PSU ?

author: MarkF
author_rank: Super Contributor
timestamp: July 02, 2015, 12:36:57 am
content: Instek now has a newer version of that power supply,Instek GPD-3303S, with rotary encoders instead of pots. I was considering the 2 3/4 digit version, GPD-3303D, but I see TEquipment is out of stock right now. I saw a review on YouTube but can't find the link any more.

author: BillW50
author_rank: Contributor
timestamp: July 24, 2015, 05:31:05 pm
content: I don't know what kind of power supply you are looking for, but for the money this one really impresses me. I personally love mine.Gopher CPS-3205 0-32V 0-5A Portable Adjustable DC Power Supply 110V/220V $57.88http://www.banggood.com/CPS-3205-0-32V-0-5A-Portable-Adjustable-DC-Power-Supply-110V220V-p-934530.htmlYouTube video is found here:

author: wraper
author_rank: Unknown
timestamp: July 24, 2015, 05:43:19 pm
content: Quote from: BillW50 on July 24, 2015, 05:31:05 pmObviously you would know if searched with google the models OP mentioned. That thing you've recommended isn't even a lab power supply, not to mention, it have only one output instead of three.

author: BloodyCactus
author_rank: Frequent Contributor
timestamp: July 24, 2015, 05:49:47 pm
content: I have the GPS-2303, 2 output version. Its a very nice psu. the OVP/OCP/shorting has saved me lotsit works great. I believe the instek design was the original design and all the others that look the same cloned the instek.I think there is photos of a teardown on tyhe GPS2303 (mine) and someone also posted teardown on the GPS4303? there are also teardown pics of GPS3303 too!

author: Gyro
author_rank: Super Contributor
timestamp: July 24, 2015, 06:59:02 pm
content: The only thing that bugs me about my GPS2303 is the lack of voltage display when the outputs are turned off. Apart from that it's been a well performing and reliable supply.All the other models in the range seem to support voltage and current limit display with the outputs off, (don't know about the 3303). I'd love to be able to implement this, but have never been able to find a schematic.Edit: The GPS3303 does have output-off displays according to the manual, so it's just the 2303 that doesn't

author: BillW50
author_rank: Contributor
timestamp: July 24, 2015, 08:11:04 pm
content: Quote from: wraper on July 24, 2015, 05:43:19 pmThen what kind of power supply is it? It definitely isn't a consumer grade power supply.http://img.banggood.com/images/upload/2014/01/SKU202665/SKU148899%20CE&SC.pdfAlso it can have as many outputs as you want. As you can chain as many of them together, since the outputs are isolated.

author: fivefish
author_rank: Frequent Contributor
timestamp: July 24, 2015, 08:35:41 pm
content: Quote from: Ecklar on July 01, 2015, 11:25:26 pmI have (3) of them... bought (1) used/working on eBay, and (2) dead from eBay that I fixed and brought back to life (bought at $50 each, and fixed for additional $10-$15 in parts).Is it any good? I like them and pretty dependable for me. It's true as advertised... will do it's rated 30V @ 3Amp, or 60V @ 3Amp (in series) or 30V @ 6Amp (in parallel). It also has a 5V output at 3Amp. I've load tested my (3) units, and can run at full load for 1+ hour. You can also parallel, series multiple GPS-3303 units for higher output voltages or current (120VDC @ 3Amps, 60V @ 6Amps).It is a true linear power supply, with a big honking power transformer, using transistor drivers and pass devices. Opamps for voltage and current comparators, optocouplers, etc. No Microprocessor inside. Very easy to repair in case you damage it. Jelly bean parts with lots of substitutions possible if you're repairing one.Output is stable. Though the LED display accuracy may be off (i.e. dependent on the AD converter/7-segment driver chip, and voltage reference), and if that's the case, download the service manual and tweak the trimmer resistors for more accurate readings on the display board. The LED displays do not control the output voltage, think of them as externally attached Voltmeter and Ammeters to the power supply. (i.e. the PSU will work even with the display board not working in other words)The only thing I don't like about them is the current and voltage pots are single-turn potentiometers. So if you want to set a specific 18.00 Volt output, you must be gentle turning the knobs or you end up with 18.01 or 17.99, and getting it exactly 18.00 needs light finger touch.Let me know if you have a specific question and I'll see if I can answer them.

author: Ecklar
author_rank: Regular Contributor
timestamp: August 01, 2015, 01:46:42 am
content: Thanks for your reply on the Instek GPS-3303 power supply. I went ahead and picked one up on sale at Tequipment. They gave me the EEV discount on top of the member price plus free shipping.I really like the simple quality construction and as you say, easy to replace jelly bean parts. With this kind of back to the basics sturdy construction, this unit will probably be on the table for many years. Yeah, the single turn Pots are a little touchy to achieve that last tenth of a volt or amp but it's not horrible and actually not bad at all.Not as cool as the more modern programable supplies, but like an old Mercedes, it's built like a reliable tank and I like it. Note: I have no connection to GW or Tequipment.

author: fivefish
author_rank: Frequent Contributor
timestamp: August 01, 2015, 03:08:22 am
content: Congrats on the purchase.Here's my 3rd GPS-3303 that I bought DOA from eBay and fixed, undergoing load testing 30V @ 3Amp using my under $50 DIY Electronic Load (EEVBlog based design)

author: Ecklar
author_rank: Regular Contributor
timestamp: August 09, 2015, 05:04:32 am
content: Quote from: fivefish on July 24, 2015, 08:35:41 pm