As a another KZfaqr pointed out, the screws on the back of the Unit are connected to the heat sink, A Potential electrical shock risk, since they are in close proximity to the power switch. The entire backplate is potentially at positive input voltage. So this plate cannot be grounded, yet the sides of the case are. Make sure you turn all the input current/voltage OFF and Disconnect before you turn the Unit on or off.

Just received my KP184. Before powering it up got it opened and checked just in case there is any similar issue with the transformer. And yes it was. Transformer was touching the mosfets above, just as the video was showing. There is a very narrow space there, just a few mm and obviously some good bump did this. So, pushed a bit the transformer and its metallic base in order to not making contact and thats it. I wouldnt even imagined that issue, so kudos to Jerry.

Got the unit with exactly same fault. Luckily, I watched your video before buying, so I knew where to look. Thanks a lot!

Add yet another one found to have this exact same bent transformer shorted to the FET issue. Glad I had watched this video a while back and knew exactly where to focus my troubleshooting today. Thanks!

Another interesting video. Thanks Jerry!

Hi Jerry. Tks for the nice video. Just waiting for one KP184 (tomorrow maybe !!) and I go to check that issue. I had problems with shipping companies before. I must to see that !!

Really nice information!

First of all, thank you for your videos. They are very helpfull. I bought one and as expected encountered some issues. The positive plug was grounded due to the contact between the transformer and one of the screws on one MOSFET (issue fixed). Like you, the diameter of the plugs is too big (4.2mm), and the cover is not grounded (issue fixed). Secondly, I found the Kapton tape unstuck on one side of the heatsink, which can create an air leakage, and thus degrade the cooling flow. I also found a bad contact in the power plug on the rear panel, you have to push the cable strongly for it hold, finally I replaced the main câble and it's a bit better. Finally, this afternoon, testing a power supply, the charge went into "OT" over temp. After removing the cover, I found the fan stopped. This was due to a bad contact in the fan connector, I could reproduce the issue by moving the connector. I found nothing special, after reconnecting the contact was correct and permanent. I think I must have touched this connector during the previous disassembly to correct the contact of the transformer with a transistor. I still have to replace the 4mm plugs and to put a main switch on the front panel. In spite of these problems, the load is functional, I tested it at 400W. And the measurements are very accurate. However, I wonder how these electronic loads could have passed the factory final tests!!!!!

1:27 “But it does need carefully testing when you get it”. I got a cheap 50W LED panel light. The earth wire was thinner than the live and neutral solder wouldn’t stick to it. Probably aluminium. So I decided to replace the whole connecting wire with a new one only to find out that the earth wire wasn’t connected to the metal(!) fixture. That caught me by surprise and reminded me to always check earth connection with these Chinese products. The panel was mounted with two small blobs of sanitary silicone in stead of a heat sink compound. Not good at all but loose earth wire was really appalling.

Same issue here. Plus, when set 10-35mA CC, the load does not indicate the right current, as if it was really low for measure. So in practice, you have measurements over 35mA. In addition, the current floats a lot.

Thanks again! In my experience the more serious Chinese brands (like Kunkin I assume) are often not unwilling to offer a partial refund if you clearly point out that your device came with some damage. Just a general remark if you have a similar situation.

Can you please provide a link to those bannana cables?

Weird fault, due a weird design requires out of scheme troubleshooting approach 😬👍💡

One strange thing I noticed, if you look at the three through the video camera, the two that are new are flashing at a different rate than the old one. You would think if they were all the same, the flash rate would look the same as well. I know they aren’t flashing, just the frame rate of the camera makes it look like they are. Strange though

Hi Have you ever tried to use the kp184 in master slave mode? (rs485) Kind regards Chris

Interesting, what kind of banana leads are you using, they look nice.

Seems like those semiconductors (MOSFETs?) on the high-side of the load ought to have been insulated from that large heat sink. It seems optimistic to have a mechanical design that requires that large heat sink is kept electrically isolated from the chassis/casing.

Jerry I don't think it was dropped in shipping. It would take a lot of force to bend those transformer tabs and note they are both bent about the same. I would think there would be other large damage to the case if it was caused by being dropped. I have seen large quantities of transformers from a supplier and some had bent mounting tabs and we had to straighten them before installing them into the product. I think it was just installed that way at the factory. As you showed in the video it was working fine until the ground test and I doubt that on an inexpensive load they would do that test in production. Nice video and well produced.

What is the purpose of the Kapton tape along the two halves of the heatsink? 🧐

Seriously dude isolate the fets from heatsink they probably skimped on thermal pads

Im +8 minutes into the video, and are puzzled why you don't inform what you paid for these new units that you so-called got a whole lot cheaper from what you calling a Chinese importer. Im familiar with the first you got for 135GBP but what is a lot cheaper and what is a Chinese importer? Ir sounds like it ain't an importer into Europe, as you also are talking about sending it back to China. You are usually pretty transparent about these things, so your viewers can relate and put it into perspective, but perhaps it will come later in the video. // Nope no info about the purchase price for this bulk purchase.