power supply voltage

[ptorric]

Hi all, i need a bit of help to identify if i can use this power supply with the european 220v ac.
It's an Aim65, that i luckily got in Ebay, inside a Cybex Data Reduction system.

I think that is a switching, because there isn't a huge voltage transformer, fuse are for 240vac also.

the three boys with the hear sinker are 426 + 436 + 3n004, not sure about them.

thank you for the help, i hope to turn it on before christmas

[ptorric]

because i think there are reader here who can love it, here your are a pic about the 12k (i think) memory expander card.

[Dr Jefyll]

ptorric wrote:

i need a bit of help to identify if i can use this power supply with the european 220v ac

In the photo we seen the label saying, "Factory wired for... ". To me that wording implies that the input voltage is selectable, and that the selection chosen at the factory can be altered in the field. IOW I think your power supply falls into category #3 of these four:

1. supplies that only accept 110 VAC
2. supplies that only accept 220 VAC
3. supplies that can be configured to accept 110 or 220 VAC
4. supplies have such broad tolerance they inherently accept any voltage as long as it's within the limits of nominal 110 to 220. These supplies do not require configuration.

Supplies that can be configured to accept 110 or 220 feature a jumper or a selector switch that must be set correctly. What that does is alter the behavior of the rectifiers and filter capacitors that produce the unregulated DC which powers the SMPS. It's a clever and simple arrangement!

In the images above, diagram (c) shows the actual input wiring of a configurable supply, while (a) and (b) clarify the two modes implicit in (c).

Note: In (a), two of the diodes of diagram (c) cease to have any function. In (b), the two capacitors of diagram (c) function as -- and are shown as -- a single capacitor. BTW, category 1 and 2 supplies usually conform to diagram (b), using a single capacitor.

Are you able to locate two fairly large capacitors of identical ratings? That's an indication your supply may be configurable. Another indication is the "Factory wired for... " label. Are you able to locate a switch or jumper?

A few warnings:

• Be aware that lethal voltages are present. When the covers are removed a shock hazard exists.
• Inappropriate setting of the switch/jumper will damage the device.
• When reconfiguring from 110 to 220, the fuse should be replaced by one with 50% of the original current rating (example: replace a 2 Amp with a 1 Amp). That's because the current draw of the supply decreases at the higher voltage. Conversely, when reconfiguring from 220 to 110, you may find it necessary to use a replacement rated at 200% of the original rating (example: replace a 1 Amp with a 2 Amp).

None of this discussion (except fuse ratings) applies to supplies using the old-style 50 Hz /60 Hz iron power transformers -- they are configured via taps on the primary, or via dual primaries that can be switched in series or parallel.

cheers,
Jeff

[ptorric]

Hi Jeff, thank you for your reply.

Yes, there are two big capacitors, i'll investigate better and post other pics in next few days (away for business sorry)

bye!

[BillO]

Power General was acquired by Ault Inc. back in 2002 or 2003 (IIRC) which has since been acquired by SL Power Electronics (www.slpower.com).

Maybe they can help.

I know the x0y0 (in this case 2060) series PS was superseded by the FLU series, but the FLU did not need input voltage configuration. IIRC they worked from about 80V to 300V.

Good luck...

[ptorric]

i think i will not procede with the original power supply, because of this label.
maybe it's more safe to use a modern pc p.s., that can deliver more or less all of the needed voltage.

btw: there is another power supply, a traditional one, that convert the +24v in a +12 and -12, not sure about why it's the needed in the board, but maybe used in lower board...it seems an a/d or a d/a converter.

[GARTHWILSON]

Quote:

a +12 and -12, not sure about why it's the needed in the board

I like to include these because

• some supertwist LCDs need a negative bias
• RS-232 line drivers that don't generate their own high voltages take less board space, because they don't need the outboard capacitors and the pins to connect them. (I use the MC145406 which has three line drivers and three receivers in a 16-pin DIP and needs no outboard capacitors, compared to only two of each in the MAX232 which needs four outboard capacitors.)
• some D/A converters need a negative voltage
• op amps (for signal conditioning for the A/D and D/A converters) using power supply voltages outside the 0-5V range work out better
• to drive an 8-ohm speaker, I use an onboard amplifier that can swing 10V
• I do my PIC programming from the workbench computer, and that requires 13V.

The exact voltage is not critical for most things. The 65SIB (6502.org Serial Interface Bus) carries ±12V (again very non-critical, for example ±9V would usually be fine) so slave devices can get what they need without requiring their own power supplies. If a device needs 5V or 3.3V at low current, it is much easier to get there with a linear regulator in a TO-92 than it is to provide only 5V and then have to use a switching power supply to go from there to ±12V.

[Dr Jefyll]

ptorric wrote:

i think i will not procede with the original power supply, because of this label.

If you are not comfortable then you should not proceed. Instead you should seek assistance of a local person who is knowledgeable -- or, as you say, replace the original supply with something else (such as a psu from a modern PC).

Probably the best choice is to seek assistance or to learn what's necessary so you can proceed yourself. I'm almost certain the original supply can be re-configured to accept 220 VAC. The procedure is quite simple. (Yes, even simpler than finding and connecting an alternative supply )

I just wish your original photo showed more detail. Can you take some more shots that fill in the blank here?

ETA: the Aim65 computer uses +24 V to operate its onboard thermal printer. If the printer is important to you, then a psu from a modern PC is not a complete solution, as it will not provide +24.