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Replacement Power Supply in Quadra 605
Posted by: Phipli on 2023-03-28 02:45:22 Should also be noted that Meanwell rates them for 4.4A at 5V, so it's not too far off the "heavier" PSUs anyway. I'll definitely give these a look, with their medical rating these should be very robust supplies given their vital use, and may be a safer bet long-term than recapping the old supplies. Thank you, the 4.0A someone quoted was confusing me. I knew they were short, but that felt more of a shortfall than I remembered.
Posted by: Tonata on 2023-03-28 07:18:40 It was me. I checked again. Most sites cite 4.4A, but mouse.fr cuts after the dot, so it lists RPT-60A as 4A for the 5V. 4.4A is closer to the 4.75 and it should not be a big difference. I will buy one instead of recaping the old one.
Posted by: MrFahrenheit on 2023-03-29 09:11:17 It was me. I checked again. Most sites cite 4.4A, but mouse.fr cuts after the dot, so it lists RPT-60A as 4A for the 5V. 4.4A is closer to the 4.75 and it should not be a big difference. I will buy one instead of recaping the old one. Mean Well has two figures. 4.0A and a 4.4A “peak”. I imagine they warranty it only for 4.0A sustained. My guess on the shift from 3.25A to 3.75A to 4+A by Apple was the realization that the 475 would get a PowedPc upgrade at some point, and the extra amps likely are needed for that, as Bolle mentions.
Posted by: Daniël on 2023-04-03 07:22:28 My guess on the shift from 3.25A to 3.75A to 4+A by Apple was the realization that the 475 would get a PowedPc upgrade at some point, and the extra amps likely are needed for that, as Bolle mentions. That would definitely make quite some sense, the card was being developed in 1993 and released the following year (if internet sources are correct), so with the 475 releasing in 1993, it might have not been initially considered. That does make me wonder if Apple would contact customers of the PowerPC upgrade, if bought through mail order or over the phone, to check if their PSU would be able to handle the additional load, and if not, whether they'd provide a replacement PSU to support the card's needs.
Posted by: MrFahrenheit on 2023-04-03 09:32:41 That would definitely make quite some sense, the card was being developed in 1993 and released the following year (if internet sources are correct), so with the 475 releasing in 1993, it might have not been initially considered. That does make me wonder if Apple would contact customers of the PowerPC upgrade, if bought through mail order or over the phone, to check if their PSU would be able to handle the additional load, and if not, whether they'd provide a replacement PSU to support the card's needs. An interesting find (attached PDF) Scroll down to "Specifications Electrical - 12" You'll see: Electrical Line Voltage 100–240 VAC, automatically configured Frequency LC Series: 47–63 Quadra 605: 50–60 Maximum Power LC/LC II: 50 W (not including monito LC III: 30 Quadra 605: 26 W Interesting to see that the maximum power draw is higher on the LC and LCII than with the LC3, and then even lower with the LC475/Q605. This runs contrary to the ratings on the power supplies for these units, I think (unless I'm interpreting these incorrectly?).
Posted by: cheesestraws on 2023-09-20 15:19:29 Thought I'd post pics of my own variant on this, now that I've finally got it done. Excuse terrible colour balance. I ended up just drilling holes in the case, and it still fits... There is an insulating sheet made of thin plastic under the PSU board.
Posted by: Phipli on 2023-09-20 15:21:38 Thought I'd post pics of my own variant on this, now that I've finally got it done. Excuse terrible colour balance. View attachment 62372 View attachment 62373 I ended up just drilling holes in the case, and it still fits... There is an insulating sheet made of thin plastic under the PSU board. Excellent work - looks like you went to the trouble of making the cable. If you're worrying about the clearance at all, grab yourself some countersunk screws.
Posted by: cheesestraws on 2023-09-20 15:23:07 looks like you went to the trouble of making the cable. There is something incredibly satisfying about a properly crimped connector. Even if I'm bad at it 🙂 If you're worrying about the clearance at all, grab yourself some countersunk screws. I wasn't sure if I'd need to countersink but it turned out I could just use plastic screws left over from building airtalks, so that's fine 🙂
Posted by: Yodd on 2024-02-22 21:36:34 I took inspiration from this thread and designed a similar mounting plate for the RPT-60A in the Dyna Comp DCF 353 PSU shell. https://www.printables.com/model/776866-apple-lc-dyna-comp-lc-353-psu-meanwell-rpt-60a-mou
Posted by: trag on 2024-02-24 21:31:44 this is a great idea, non-destructive edits are best. the connectors on the Meanwell board are JST VH, get some maybe with leads already on and splice onto power switch etc. I think that Phoenix Connectors also has those connectors. At least, I remember sourcing some for adapting ATX PS to the Umax S900. I'm not certain I got htem from Phoenix.
Posted by: acn128 on 2024-05-31 06:02:24 Hi! I tried to replace the PSU from my Performa 475 (TDK brand) with a RPT-60A. I bought some connectors (JST-VH) and crimped them to the original cables, so no soldering had to be done to the Meanwell PSU. To mount the Meanwell in the case, I 3D-printed the base by SpocksBeer (from Post #21) in PETG and screwed everything together. But when powering it on on my workbench (without the computer attached), I only heard a loud bang and the fuse blew... After a while, I looked inside the case, and it seems that a spark between a heatsink (HS1 on the Meanwell documentation PDF) and the metal case ignited. I have to admint that I forgot to add insulation between the PSU and the upper case, so that might have been the problem... (Oh, and the PSU seems to be dead now, but I've already ordered a replacement...) My question here is: Do I have to take anything else into account before burning the next RPT-60A? 🙂 I've added a layer of duct tape and electrical tape on the cover. I also included the connection between the outer case and the two screws M1 and M2 as noted in the documentation ( https://www.meanwell.com/Upload/PDF/RPT-60/RPT-60-SPEC.PDF ) Do I need to add something else? Thank you very much! Regards, Anna
Posted by: MrFahrenheit on 2025-06-26 19:39:40 I’m back on this project thanks to being reminded of it in my other thread about fixing a ton of Macs. I’m staring at my wires and the wires in the photos people post for using the Meanwell power supply, and I’m confused. The LC wiring plug has blue, empty, yellow, orange, empty, black, black. I see that the meanwell puts black wires in the middle. Are they both the same? Can they interchangeably be flipped between black/black? Or is one black different than the other?
Posted by: pizzigri on 2025-06-27 02:08:30 No makes no difference, black is GND and it’s unified on the PCB of both logic board and PSU
Posted by: killvore on 2025-06-27 07:55:24 I think I posted this in the other thread but I hadn't actually carried it out at that point - I connected mine like this and it works great! I removed the connectors on the Mean Well, stripped the ends of the wires from the connector I took from the LC PSU, and taped both the Mean Well AND the inside of the LC PSU case to make sure it didn't touch and short. Works great! The LC it's in has been running Snooper RAM tests all day, no issues
Posted by: Andy on 2025-09-18 04:55:58 Just rebuilt two LC PSUs with the Mean Well RPT-60A. They both work great! Didn't bother with making a bracket. Used some double sided tape, and then made little cables to connect the two grounding holes.
Posted by: croissantking on 2025-12-22 14:07:39 Quick tip when rebuilding a Dyna Comp, keep the heatsink/bracket from the original PCB, shorten it and reuse it so that the top cover can screw in on both ends.
Posted by: croissantking on 2025-12-22 15:43:48 Here's my finished PSU rebuilt – tested and perfectly working. it's amazing how, presumably just by coincidence, these Mean Well units feel like they're almost perfectly designed for the LC PSU housings. With thanks to @Yodd for sharing their excellent mounting plate design, which I got printed with JLCPCB.
Posted by: croissantking on 2025-12-25 04:21:46 made little cables to connect the two grounding holes. Oh, I should probably do this. The PSU is isolated from the case because it’s on a 3D printed stand-off.
Posted by: Fred1212 on 2026-01-03 18:29:17 Just wondering isn't it easier and cheaper to recap the original board in these? I've just done three and all worked perfectly after replacing the caps
Posted by: AEChadwick on 2026-01-03 18:52:28 Just wondering isn't it easier and cheaper to recap the original board in these? I've just done three and all worked perfectly after replacing the caps oh, sir... If "easy" and "cheap" were the qualifiers, none of us would have this infuriating hobby. (ツ)
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