Confirming PSU spec for steppers.

[Rogue]

Here's the plan - listing is indicative of order, should roughly correlate to this:



It's a little rough, I rushed it for the post. You might need to pretend there is a relay-controlled bleeder. And you might need to pretend there are any outputs to the rest of the world, but hey, that's the power of i-m-a-g-i-n-a-t-i-o-n!

Fused IEC Chassis Plug (23-0360) with 5A slow-blow fuse (20-1072)
High Current Toggle Switch DPST (on/off) rated 250VAC@10A/12VDC@20A (75-0253)
Splits out to
- 12mm 240V Green Neon indicator (42-0330)
- 24v system
- 70V system (via relay)
- potentially other systems, ie BoB etc.

24VDC System (well, 23-ishV)

Transformer: PCB transformer 230V 12VA 2x9V (88-3877)
Bridge Rectifier: Woo5 1.5A 50V Bridge Rectifier (47-3190)
Indicator: LED to be determined (probably have something suitable upstairs)
Smoothing Cap(s): 2000uF according to my magic spreadsheet, so 2 x 1000uf 63v Caps
Bleed Resistor: Not needed, but otherwise I worked it out as 3.5kOhms 1W
Toggle switch 24V for turning on 70V system

70VDC System

Relay: 24VDC 4PDT, rated 240VC@7A (60-1310)
Transformer: Well this is annoying, see below.
Fuse: Slowblow 15A in fuse holder
Bridge Rectifier: 35A 600V Bridge Rectifier (42-3228)
Indicator: LED to be determined (probably have something suitable upstairs)
Smoothing Cap(s): 4 x 4,700uF 100V caps (11-2912)
Bleed Resistor: I work this out as a 5 second bleed = 2 kOhm 3W, controlled by a relay wired NC.


Transformer for 70V system - Rapid has 500VA 2x50V transformers which should give me 50VDC@10A in parallel. I'd prefer 625VA but they don't carry 2x25 and the 2x50 has a 1-2 month wait from order. As I'll be sourcing this component last I have time to hunt around. A few other links to sources were posted in the thread; I'll check up on them later.

The wires to the relay that turns on the 70V will pass through another, normally open relay. This second relay is powered

Various crimps, wire and connectors should be easily sourceable at the local shop.

If I don't post for a month, my widow will probably be selling my stuff on ebay so keep an eye out for some bargains - she might be selling it for what I told her it cost before I got turned into crispy bacon...