Hello everyone,
This is my first thread, and I am new here. I am part of the 68kMLA forum, and I was referred over here by one of the members there who is a member here as well.
I have a power supply from a Power Mac 8100 (Delta Electronics, Model # DPS-225AB Rev: A0, Apple Part Number 614-0040). It worked fine prior but, being close to thirty years old, it was time to recap. I have done a lot of capacitor replacement, but am by no means an expert at all. I looked up the replacement parts and ordered on Mouser. All electrolytics were replaced with same capacitance and voltage rating (or higher voltage if the identical could not be found). After reinstalling, all seemed to be well: machine starts normally, everything runs. However, after about five minutes, the entire PSU shuts down all of a sudden. Dead. This is a soft power on power supply: it has no on/off switch, and it supplies a +5V trickle current to the motherboard for soft power on/off signaling. If I try to start it right when it dies, I hear a switch/relay click inside and then right off again. I can do it about three times till it won't do anything else. Only if I unplug the supply, let it sit for 15-20 minutes, then try again will it restart again, only to last for five minutes.
I checked output voltages, and all grounds are connected properly, all +5V read 5, all +12V read around 12, and all -12 are around that too. They all are consistent: the output is dead on until the supply suddenly shuts off.
At this point, I do not know enough to troubleshoot further. Anything else to try, and any more information I can supply to assist in figuring this out?
This is my first thread, and I am new here. I am part of the 68kMLA forum, and I was referred over here by one of the members there who is a member here as well.
I have a power supply from a Power Mac 8100 (Delta Electronics, Model # DPS-225AB Rev: A0, Apple Part Number 614-0040). It worked fine prior but, being close to thirty years old, it was time to recap. I have done a lot of capacitor replacement, but am by no means an expert at all. I looked up the replacement parts and ordered on Mouser. All electrolytics were replaced with same capacitance and voltage rating (or higher voltage if the identical could not be found). After reinstalling, all seemed to be well: machine starts normally, everything runs. However, after about five minutes, the entire PSU shuts down all of a sudden. Dead. This is a soft power on power supply: it has no on/off switch, and it supplies a +5V trickle current to the motherboard for soft power on/off signaling. If I try to start it right when it dies, I hear a switch/relay click inside and then right off again. I can do it about three times till it won't do anything else. Only if I unplug the supply, let it sit for 15-20 minutes, then try again will it restart again, only to last for five minutes.
I checked output voltages, and all grounds are connected properly, all +5V read 5, all +12V read around 12, and all -12 are around that too. They all are consistent: the output is dead on until the supply suddenly shuts off.
At this point, I do not know enough to troubleshoot further. Anything else to try, and any more information I can supply to assist in figuring this out?
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