How To: Dual Powersupply Switchbox

BombTek · 01-04-2003, 09:44 PM

///To approving mod: Due to the size limit I was unable to post images(even by linking them to My Website...) if approved the can be added fairly easy.. Also would like a additional comments thread availible, so if one could be created thanks BT///

TWO PSU SWITCHBOX

By: Bombtek

Want to add a second power supply to your system but don’t want to cut and splice wires? Here’s your solution: Build a switchbox.

How it works: PSU1 turns on, the 12v line connected to the switchbox trips a relay and closes two connections on PSU2 and turns it on. There you have it.

Parts you need:

(1)ATX PSU extension cable. (I used a 4” one from a local computer store)
(1)Radio Shack Relay PN: 275-249A
(1)Radio Shack Project Box PN: 270-1801
(1)Radio Shack PC Board PN: 276-148A
(1)Female 4-pin Molex connector, www.jameco.com PN: 42067
(2)Pins for Molex connector, www.jameco.com PN: 42649
(1ft)18AWG wire, www.jameco.com PN: 125735(red) or 125786(black)
Optional (1)40mm fan 12v. (I already had one)
[img]

Tools you need:

1. Soldering iron
2. Solder w/ flux inside
3. Cross-tip screwdriver #
4. Small flat head jewelers screwdriver
5. Dremel tool w/ cutting wheel (or a sharp razor knife and a file)
6. Wire strippers
7. Needle nose pliers
8. Sandpaper or file

Let’s get started:

1. Prepare a clean work area. I used the kitchen table and put down some newspaper to keep from messing the table up.

2. Break out all your parts and check them for any signs of damage. It’s hard to take a part back if you’ve already tampered with it. Keep all bags and packaging until finished.

3. Cut two four inch lengths of 18AWG wire and strip 1/8th inch at one end and 1/2 inch at the other.

4. Take two Molex pins slide them over the two wires on the 1/2 inch stripped side. Crimp using the needle nose pliers. It’s easiest to bend one side first, then the other side and then crimp them both tight. Set aside for later.

5. Take the PC board out of the package and break it in half along the perforated line. Take the sandpaper and sand the rough edge down from the edge you broke from. While sanding take a hair extra off that side so it will fit in the box good.

6. Take the ATX extension cable and using the jewelers screwdriver and pop all the pins out of the female side of the connector except pins 7(Black) and 8(gray) and pins 14(green) and 15(black). If you look down into the connector you’ll see little groves on the left and right of each pin. Push the screwdriver in one side, which pops the little finger in and while slightly pulling on the wire you’re removing push the screwdriver in the other side of the pin and it should come right out.
[img]

7. You should now have all but those four wires remaining. Cut the four wires in half separating them from the rest of the cable. Strip the end of each wire 1/8th inch. On the connector cut the two fingers off the sides.

8. Time to mod in the project box. Lay the box down open side up. The side to your left will be for the hard drive connector and the side across for the ATX connector. Notice the ribs in sets of two on each side of the box. Using your dremel or knife and cut the four ribs on your side completely off. Next you’ll need to shave the four center studs down until they are 1/8th inch high instead of 1/4 inch.
[img]

9. If you plan on adding the fan, drill two 1/4 inch holes on each of the two unused sides. On the box lid place the fan on top and trace the inside diameter of the fan and cut a hole. Place the fan so that it will blow into the box. Run the power wires into the hole before mounting. Mount the fan using a good two part epoxy. (Screws will hit the relay).
[img][img]

10. Place the hard drive connector (centered and rib side up) against the left side of the box so that the pin opening is facing out. Trace the outline. Repeat with the far side with the ATX connector (locking tab up), again pins out. Try to be very precise while tracing the outline, the tighter the fit the better the hold on the connector. Cut the holes and file smooth.
[img]

11. Check each hole for a good fit on the connectors. Leave the hard drive connector in the box halfway. Remove the ATX connector.

12. Take the PC board and place it with the copper lined holes facing down and the side you sanded facing to your left. Now take the relay and line the pins on the PC board to the far right of the board centered front to back making sure to leave at least two holes visible on all sides of the relay. (I only left one hole and had to shave a bit off the relay). The relay should stay in place.

13. Take note of the relay diagram on the back of the packaging. You will wire the two wires from the hard drive connector into the two holes in front of the two coil pins. The other four wires in pairs (pins 7&8 and pins 14&15) one on the common and the other on the NO (normally open) side. Feed each stripped end into the hole beside the respective relay pin and solder in place and make a bead of solder to connect it to the relay pin. Solder in the rest of the relay.
[img][img]

14. For the optional fan solder the fan power leads in parallel with the coil circuit.

15. Snap the two pins into the hard drive connector ensuring to line them up with the yellow and black wires of the PSU you’ll be connecting to. Or you can line them up on the ribbed side. If you are using the fan polarity DOES matter so be sure to match them up correctly!
[img]

16. Slide the PC board in starting with the relay side. Tilt it down until it bottoms out on the studs you shortened, and then push the other side down to the bottom. It may require a little spreading of the box, but this is because of the good fit.

17. Push the ATX connector through the hole you made for it.

18. Push the hard drive connector all the way in now.
[img]

19. Tuck in all your cables and put the lid on.
[img]

20. Connect to the PSU and test for at least 24 hrs to make sure all is well.

21. There you go. You very own relay switch box.

This very switchbox has been running my main rig non-stop since May 02.

If you want these instructions with images check out My Website...

thirstydg · 02-01-2003, 10:44 PM

Very good I liked it.
I did something close to it but I used the relay to open120 Vac for my main's fan and all my 12Vdc adapter's for printer and speakers.
I think I will build one I see a use to having one more gadget around

BombTek · 02-03-2003, 05:57 PM

Thanks Thirsydg! I am just glad to help out. It beats the socks of trashing a PSU by cutting a bunch of wires..

thirstydg · 02-04-2003, 09:11 PM

I picked this mod up on line it's simple and very quick to make yet functional like the power supply mod.
I have looked for this site to no avail and can not find it but anyhow i do know how it is made if you would like plans let me know

althes · 03-01-2003, 11:02 AM

Think I will be trying this

**specmike** · 12-11-2003, 05:15 PM

I love this mod. I have an extra power supply running 2 120gb Maxtor HDs mounted in a hobby box bolted to the power supply. There was no room for the HDs inside the case and I also run some fans with the external HD. All in all, a great use for a power supply that was just sitting and I removed some heat from my case.

Thanx for the great details. I deviated from the plan a bit as I did not go out and find an extra female ATX plug to use. I just hardwired it.

Mike.

BombTek · 12-12-2003, 05:22 PM

You're certainly welcome Mike! I am just glad that ppl are able to get some use out of it...

-BT

01-04-2003, 09:44 PM	#1
BombTek Good to be home... Join Date: Feb 2001 Location: Ft Walton Beach, FL Posts: 2,246	How To: Dual Powersupply Switchbox ///To approving mod: Due to the size limit I was unable to post images(even by linking them to My Website...) if approved the can be added fairly easy.. Also would like a additional comments thread availible, so if one could be created thanks BT/// TWO PSU SWITCHBOX By: Bombtek Want to add a second power supply to your system but don’t want to cut and splice wires? Here’s your solution: Build a switchbox. How it works: PSU1 turns on, the 12v line connected to the switchbox trips a relay and closes two connections on PSU2 and turns it on. There you have it. Parts you need: (1)ATX PSU extension cable. (I used a 4” one from a local computer store) (1)Radio Shack Relay PN: 275-249A (1)Radio Shack Project Box PN: 270-1801 (1)Radio Shack PC Board PN: 276-148A (1)Female 4-pin Molex connector, www.jameco.com PN: 42067 (2)Pins for Molex connector, www.jameco.com PN: 42649 (1ft)18AWG wire, www.jameco.com PN: 125735(red) or 125786(black) Optional (1)40mm fan 12v. (I already had one) [img] Tools you need: 1. Soldering iron 2. Solder w/ flux inside 3. Cross-tip screwdriver # 4. Small flat head jewelers screwdriver 5. Dremel tool w/ cutting wheel (or a sharp razor knife and a file) 6. Wire strippers 7. Needle nose pliers 8. Sandpaper or file Let’s get started: 1. Prepare a clean work area. I used the kitchen table and put down some newspaper to keep from messing the table up. 2. Break out all your parts and check them for any signs of damage. It’s hard to take a part back if you’ve already tampered with it. Keep all bags and packaging until finished. 3. Cut two four inch lengths of 18AWG wire and strip 1/8th inch at one end and 1/2 inch at the other. 4. Take two Molex pins slide them over the two wires on the 1/2 inch stripped side. Crimp using the needle nose pliers. It’s easiest to bend one side first, then the other side and then crimp them both tight. Set aside for later. 5. Take the PC board out of the package and break it in half along the perforated line. Take the sandpaper and sand the rough edge down from the edge you broke from. While sanding take a hair extra off that side so it will fit in the box good. 6. Take the ATX extension cable and using the jewelers screwdriver and pop all the pins out of the female side of the connector except pins 7(Black) and 8(gray) and pins 14(green) and 15(black). If you look down into the connector you’ll see little groves on the left and right of each pin. Push the screwdriver in one side, which pops the little finger in and while slightly pulling on the wire you’re removing push the screwdriver in the other side of the pin and it should come right out. [img] 7. You should now have all but those four wires remaining. Cut the four wires in half separating them from the rest of the cable. Strip the end of each wire 1/8th inch. On the connector cut the two fingers off the sides. 8. Time to mod in the project box. Lay the box down open side up. The side to your left will be for the hard drive connector and the side across for the ATX connector. Notice the ribs in sets of two on each side of the box. Using your dremel or knife and cut the four ribs on your side completely off. Next you’ll need to shave the four center studs down until they are 1/8th inch high instead of 1/4 inch. [img] 9. If you plan on adding the fan, drill two 1/4 inch holes on each of the two unused sides. On the box lid place the fan on top and trace the inside diameter of the fan and cut a hole. Place the fan so that it will blow into the box. Run the power wires into the hole before mounting. Mount the fan using a good two part epoxy. (Screws will hit the relay). [img][img] 10. Place the hard drive connector (centered and rib side up) against the left side of the box so that the pin opening is facing out. Trace the outline. Repeat with the far side with the ATX connector (locking tab up), again pins out. Try to be very precise while tracing the outline, the tighter the fit the better the hold on the connector. Cut the holes and file smooth. [img] 11. Check each hole for a good fit on the connectors. Leave the hard drive connector in the box halfway. Remove the ATX connector. 12. Take the PC board and place it with the copper lined holes facing down and the side you sanded facing to your left. Now take the relay and line the pins on the PC board to the far right of the board centered front to back making sure to leave at least two holes visible on all sides of the relay. (I only left one hole and had to shave a bit off the relay). The relay should stay in place. 13. Take note of the relay diagram on the back of the packaging. You will wire the two wires from the hard drive connector into the two holes in front of the two coil pins. The other four wires in pairs (pins 7&8 and pins 14&15) one on the common and the other on the NO (normally open) side. Feed each stripped end into the hole beside the respective relay pin and solder in place and make a bead of solder to connect it to the relay pin. Solder in the rest of the relay. [img][img] 14. For the optional fan solder the fan power leads in parallel with the coil circuit. 15. Snap the two pins into the hard drive connector ensuring to line them up with the yellow and black wires of the PSU you’ll be connecting to. Or you can line them up on the ribbed side. If you are using the fan polarity DOES matter so be sure to match them up correctly! [img] 16. Slide the PC board in starting with the relay side. Tilt it down until it bottoms out on the studs you shortened, and then push the other side down to the bottom. It may require a little spreading of the box, but this is because of the good fit. 17. Push the ATX connector through the hole you made for it. 18. Push the hard drive connector all the way in now. [img] 19. Tuck in all your cables and put the lid on. [img] 20. Connect to the PSU and test for at least 24 hrs to make sure all is well. 21. There you go. You very own relay switch box. This very switchbox has been running my main rig non-stop since May 02. If you want these instructions with images check out My Website... __________________ Click those ads, give what you can, keep AbxZone alive! Or I'll blow you up!! Last edited by BombTek : 03-02-2003 at 02:38 PM.
(Offline)

02-01-2003, 10:44 PM	#2
thirstydg Registered User Join Date: Feb 2003 Location: the Heart land Posts: 115	Very good I liked it. I did something close to it but I used the relay to open120 Vac for my main's fan and all my 12Vdc adapter's for printer and speakers. I think I will build one I see a use to having one more gadget around
(Offline)

02-03-2003, 05:57 PM	#3
BombTek Good to be home... Join Date: Feb 2001 Location: Ft Walton Beach, FL Posts: 2,246	Thanks Thirsydg! I am just glad to help out. It beats the socks of trashing a PSU by cutting a bunch of wires.. __________________ Click those ads, give what you can, keep AbxZone alive! Or I'll blow you up!!
(Offline)

03-01-2003, 11:02 AM	#5
althes I am at work. Join Date: Jan 2002 Location: Massachusetts Posts: 464	Think I will be trying this __________________ Althes ebay:althes heatware:althes
(Offline)

12-11-2003, 05:15 PM	#6
specmike Yes, Yellowbeard Join Date: Oct 2002 Location: Metro Atlanta, GA. Posts: 2,626	I love this mod. I have an extra power supply running 2 120gb Maxtor HDs mounted in a hobby box bolted to the power supply. There was no room for the HDs inside the case and I also run some fans with the external HD. All in all, a great use for a power supply that was just sitting and I removed some heat from my case. Thanx for the great details. I deviated from the plan a bit as I did not go out and find an extra female ATX plug to use. I just hardwired it. Mike. __________________ CORSAIR TECH SUPPORT
(Offline)

12-12-2003, 05:22 PM	#7
BombTek Good to be home... Join Date: Feb 2001 Location: Ft Walton Beach, FL Posts: 2,246	You're certainly welcome Mike! I am just glad that ppl are able to get some use out of it... -BT __________________ Click those ads, give what you can, keep AbxZone alive! Or I'll blow you up!!
(Offline)

Thread Tools
Show Printable Version Email this Page
Display Modes
Linear Mode Switch to Hybrid Mode Switch to Threaded Mode