Tips & Tricks

Personal Iris PSU replacement

Introduction

Powersupply problems are not uncommon with these systems.

Unplug the powercord, then open the opposite side of the E-Module and remove the sheetmetal. The powersupply has 2 replaceable fuses which are worth to check as well as the proper cabling. One fuse is on the small daughtercard, the other is next to that card and usually covered with a blue plastic cap.

If the PSU is completely dead and replacing with an original one or having it repaired it is not an option it might be a a possibility to swap another PSU into the Personal Iris. You may have seen pictures on the web that show systems equipped with PC powersupplies.

This guide is intended to supply you with all the required information.

Warning! Proceed only if you feel really safe about handling powersupplies and electrical cabling. If you have the slightest doubt do not continue on your own.

Powersupply

The original Personal Iris is made in Malaysia by L+H. The box below contains all relevant information taken from the label of such a PSU. This will help in finding an appropriate replacement:

MODEL        CM-E2348A/115-230
INPUT        7A/4A 115/230V AC (50-60Hz)
OUTPUT       350W
V1           +5V @ 45A
V2           +12V @ 9A
V3           -12V @ 2A
P/N          853874-002 (9430801)

Color Code

This color code applies to the PSU side of the cables. The fan cable might be the exception to the rule given here. There is a brown wire used but the fan typically needs +12V and not -12V (so the wire should be orange instead of brown).

green        GND
white        +5V
orange       +12V
brown        -12V
red          sense+
black        sense-
blue         PFD

Pinouts

Personal Iris PSU

E-Module Power

    -|---------              |           pin #1 marker
   | U O O O O |             +5V         white                pin #1, #4, #7, #10, #13 (top row)
   | O O O O D |             +12V        orange               pin #2
   | D O O O O |             -12V        brown                pin #5
    -----------              sense+      red                  pin #8
                             sense-      black                pin #11
                             PFD         blue                 pin #14
                             GND         green                pin #3, #6, #9, #12, #15 (bottom row)

Internal SCSI Power

    -|-------              |           pin #1 marker  
   | U O O U |             +5V         white                  pin #1
    ---------              GND         green                  pin #2, #3
                           +12V        orange                 pin #4

On/Off-Switch

    -|---                  |           pin #1 marker  
   | U U |                 Hot         white                  115/230V
    -----                  Return      black                  0V

Fan Power

    -----               
   | U U |                 +12V        brown                  (some docs say "-12V" which matches the color code)
    -----                  GND         green

Baby-AT Powersupply

A word of Warning

Do not rely too much on the color code given here, there apparently is no strict standard although in most cases the coloring scheme is the one following below.

Motherboard Power

PWR GOOD    orange                 pin #1
+5V         red                    pin #2
+12V        yellow                 pin #3
-12V        blue                   pin #4
GND         black                  pin #5
GND         black                  pin #6

GND         black                  pin #7 
GND         black                  pin #8
-5V         white                  pin #9
+5V         black                  pin #10
+5V         black                  pin #11
+5V         black                  pin #12

Drive Power

     _______               +5V         red                    pin #1
    /       \              GND         black                  pin #2, #3
   | 1 2 3 4 |             +12V        yellow                 pin #4
    ---------

Instructions

Finding a PSU

Have a look at the specifications of the original powersupply. The replacement PSU needs about 350W, the tricky part might be finding a replacement that at least almost matches the figures given for the three required voltages (see V1-V3 above). If the PSU doesn't supply enough power on some lines it is a good idea to keep the load a bit down (i.e. don't put in 3 harddrives or maxed out graphics).

Removing the original PSU

Open both sides of the machine and remove the emodule as well as the sheet metal on the PSU side. On the latter side there is a large part covering most of the side and a smaller piece covering the PSU itself. Facing the open PSU check the fuses located close to the power connector on the back of the Personal Iris.

Preparing the wires

On both sides there are wires that need not be connected. For the PC (Baby-AT assumed) powersupply it is PWR GOOD and the -5V wire, on the Personal Iris there are three wires which are only needed by the original powersupply: sense+, sense- and PFD.

On the Baby-AT powersupply the wires from the motherboard connector as well as the wires from one drive connector are needed. Cut the connectors off, isolate the two unneeded wires and unisolate the tips of the remaining ones (put some solder on the tips).

Then cut off the wires on the powersupply of the original PSU. This way the cables within the chassis itself remain unharmed and you can simply attach a working original powersupply if you happen to find one. Again isolate the three unused wires and prepare the remaining ones as above.

Putting it together

Using insulating screw joints you can now connect the cables coming from the Baby-AT PSU to the ones coming from the connectors that once were attached to the original powersupply. Take care that you don't mix things up here, so don't rush.

If all is set attach the "new" PSU using the original connectors. Don't forget the chassis grounding and also think of a solution for the on/off switch (how this can be done depends on what you have found).