External Drive Array Project

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Purpose:

The goal of this project is to create a small external drive tower using off-the-shelf components and a custom decorative enclosure. The enclosure will be able to accept up to 3 SATA drives (SATA I and SATA II) supporting transfer rates up to 3 Gbps.

The main use for the drive array will be for external storage for the Book Server running Windows Home Server . This will allow the Book Server to retain it's look while allowing easily accessible storage and expandability.

Parts:

• Thermaltake iCage 3.5" aluminum drive cage.
• 4-Port multilane SATA2 adapter for the host
• 4 Port multilane adapter for the drive enclosure
• Infini-band multilane cable supporting 4 drives (attaches to PC to drive array)
• picoPSU 12-12 V Power supply and 110 V brick
• Lian-Li TR-03 multifunction display
• 12V Relay (SPST - normally open) for automatic on/off of array.
• Shielded 2-wire cable for relay.
• Power On-Off switch (SPST On/Off)
• Wire connectors
• Parts to build the enclosure.
• Seagate 500 GB SATA2 hard-drive.
• SATA power Adapters

Technical Information

The following project involves making some minor modifications to a computer power supply. Care must be taken in making all connections secure and Terracode assumes no liability for failure to take proper precautions.

Multilane adapters and Infini-Band cable

The Multilane adapters is a small device that has connections for up to 4 SATA hard-drives. One adapter goes in the host computer where the SATA connections from the motherboard will connect. The second Multilane adapter is for attachment to the external enclosure and provides connections to the hard-drives. The Infini-Band cable will carry the signals from one multilane adapter to the other and up to 3 Gbps. The cost for the adapters were relatively cheap compared to the cable. The cable turns out the be one of the more expensive pieces of this puzzle (excluding the hard-drives) at $60 for 6' cable. The prices vary on the internet and will run close to $60 to $118 for a 6' cable.

Thermaltake iCage

The Thermaltake iCage was chosen because it it a pre-built aluminum drive cage with a large fan attached. The cage supports 3 drives and is meant to be an adapter to convert 3, 5.25" drive bays to 3, 3.5" drive bays for a Tt computer case. It is perfect for this project and saves time trying to fabricate or finding a donor case for a drive cage.

Power Supply and Relay

A DC-DC power supply with an external brick similar to what was used on the Book Server was used in this project. A micro-ATX powers supply was modded for testing purposes. The power supply's motherboard ATX connector will have to be modified to remove all unused wires. The only wires that will be used is the 'Power-On', GND, Power-Ok' wires. All others will be removed from this connector. The power supply has 4 power connectors for hard-drives. The P4 connector and floppy connector will also be removed because they will not be needed.

The 12V relay will connect to the 'Power-On' and GND wires to a 12V power connector on the host computer. When the host computer is turned on, it will trip the relay which will turn on the external drive array power supply. The power will also turn off when the main PC power is turned off. A separate ON-OFF button will be installed to turn off the drive array from being activated by the host PC.

Enclosure

I initially was planning on buying a decorative box to mount the components for the drive array (aka. Book Server), but decided to look into building a custom wood enclosure.

Procedure:

Enclosure Fabrication:

1. Below is the enclosure I put together. It still needs sanding, filling, back and front panels. The box is 6.5" high x 9.75"" wide x 5.5" deep. After prepping, the box will be stained and sealed.

The drive cage and power supply will sit next to each other.

The top edge of the box was routed to give a decorative look and the screw holes filled and the box was sanded. The front cover was cut to size and will be attached with metal inserts and brass machine screws. The box will be stained a dark cherry and the inside painted silver.

The stained, painted and sealed box ready for the components.

I ordered custom cut light bronze Lexan panel for the front and a dark bronze for the back from Interstate Plastics and am awaiting it's delivery.

The micro-ATX power supply was modified to remove the ATX connector and unused wires. Only the drive power, PWR-On and PWR-OK wires will be used. The power supply was tested using a power-supply tester after modification to confirm it still works and were no shorts. This will be used to test the relay and other components.

Continue to Page 2 - Putting it all together

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