New build with recycled parts on a ridiculous budget 120cm*60cm work area

[Clive S]

Quick question my AM882's the power in is marked AC for both inputs which one is the + and which one the -?

As Neale has said. But not all AM882 are the same I think you have bought them from different sources so check all of them. I think it is the AM882H that can handle AC or DC and the AM882 is only DC. As usual could be wrong.

[Nr1madman]

Omg that's some low price transformers :D
Good find and I'm happy that you are back on track!

Wish they delivered to Sweden ;)

Skickat från min SM-N910C via Tapatalk

[Nr1madman]

For the fuse question.. think it might blow when charging the caps..

Skickat från min SM-N910C via Tapatalk

[Nr1madman]

I think the voltage will drop when you connect a load on the secondary side. Now you only have the caps connected right?

Skickat från min SM-N910C via Tapatalk

[m_c]

Assuming input voltage is at rated 230V, your output voltage open circuit is going to be at 52VAC (rated output voltage plus the regulation rating of 4%).
Multiply that by root 2, gives 73.5V peak voltage.

Now if your input voltage is at 250, which puts it around 8% above the rated voltage, so your output voltage will be proportionally higher, at 79.4V peak.

Now all you need is a sudden deceleration on a couple axes, and the energy dump back into the DC side can potentially push everything overvoltage.

If you search for my Triac retrofit thread, there's a big post there explaining all this.

[Davek0974]

Now all you need is a sudden deceleration on a couple axes, and the energy dump back into the DC side can potentially push everything overvoltage.

Thats the important bit, i would get this voltage down before connecting drives.

[Desertboy]

Have ordered a 45v 1kva which will solve the problem whilst I'm waiting I took the time to start stripping out the box and recovered some nicer wiring conduits. Also fitted a proper stop switch to it.

Friend is going to fibreglass repair the damage for me I might even paint it ;)





There's loads of space in here should I put the transformer in here as well and fit a 4 120mm pc fans two blowing in across the am882's and two sucking out the side of the transformer and leave a nice gap so the air can flow, I want to make sure the caps get good air flow over them.

It would be good to fit the transformer at the top of the box but it weighs 8kg making the box top heavy so it'll go at the bottom if i do fit I think the key will be good air flow and lots of it. I have a better on/off switch which is rated to 2hp (I think might be 3) ac3 so I think should be ok for the PSU.

[Clive S]

Have ordered a 45v 1kva which will solve the problem whilst I'm waiting I took the time to start stripping out the box and recovered some nicer wiring conduits. Also fitted a proper stop switch to it.

Friend is going to fibreglass repair the damage for me I might even paint it ;)

If you can cancel the order and reorder a 625Va as it should suite you better 45V is a good choice

[Nr1madman]

I keep forgetting.. did you plan on using separate 5v psu or power it from usb?

If using psu then it looks tight to get that connected there as well...

Skickat från min SM-G955F via Tapatalk

[Desertboy]

I keep forgetting.. did you plan on using separate 5v psu or power it from usb?

If using psu then it looks tight to get that connected there as well...

Skickat från min SM-G955F via Tapatalk

The BOB is powered by usb, need to get 12v PSU in there yet ;) If I'm reading the BOB properly it can only be powered by USB unless you solder your own connections. If you have the same BOB get your male to male usb cable now ;) although you can hack something together at a push I originally powered it up with a hacked 4 pin molex (Hard disk power cable) to USB.

I hope the AM882 is a straight swap for the AM882h as I used the broken one as pattern for setting up whilst I'm waiting for the new one.