This project was a quest to build a convenient connector panel for my bench power supply.

My Agilent 66309D Mobile Communication DC Source is a terrific 2-channel bench power supply.  Originally designed for engineers who are prototyping and designing cell phones, it has very precise regulation, control over voltage & current, programmability and measurement capabilities including an independent digital multimeter function.

The only problem is that all the connectors are on the back.

My first solution was to bring wires up and semi-permanently attach them to a breadboard.  But that isn't very versatile.  For a while, I've been thinking about a better solution -- bring the connections up to a separate panel.

I designed the panel in an antiquated version of Corel Draw and uploaded it to Ponoko.com.  In just a few days, they laser cut the design into black acrylic and shipped it to me.  The precision of their cutting and engraving is very impressive.  They can engrave text with the laser, so I did that for the legends, then filled them with white paint before peeling the protective paper off.

Here are some pics:

Laser cut parts
Laser Cut Parts
(click for a larger view)
Edge detail
Edge Detail
(click for a larger view)
Engraved Word
Engraved Word
(click for a larger view)
The Letter S
The Letter S . . . Really Close
(click for a larger view)
Here's Looking At U
Here's Looking At U
(click for a larger view)
The Letter V
The Letter V
(click for a larger view)

It's interesting to me how the laser engraves a deep but very narrow channel around the perimeter of the letter.  Of course, this is controlled in the design file by selecting text borders and setting their depth with the color of the border (or fill) in the design.  Still, it's nifty to see how it's rendered in real life.

All the parts were cut from a single piece of acrylic.  I kept everything within Ponoko's specified boundaries, but the actual panel was a bit larger.  I wish I could have used the remaining area to make the side panels bigger.

The panel is assembled using Plastruct Plastic Weld which is a water thin cement that bonds the plastic together on a molecular level.  It requires a flush fit and uses capillary action to draw the cement into the joint.  The laser cutter yields a very smooth edge that took the bond quite well.

Here's the completed panel:

 


Completed Panel
Completed Panel
(click for a larger view)
Panel Front
Panel Front
(click for a larger view)
Panel Rear
Panel Rear
(click for a larger view)

So now I have a convenient way of plugging projects in to get power.  I can use simple banana patch cables so when I want to set a project aside, I can just unplug, put the protoboard on a shelf and plug another one in.

In case you're wondering, the connectors are all Pomona shrouded banana jacks.  The power supply has remote sensing capabilities & independent grounds, so that's why each channel has 5 connectors:  + / - power, + / - sense and gnd.  The switches allow me to select whether sensing is done at the panel or remotely wherever I place the sense wires.  The power supply uses the sense wires to compensate for any voltage drop in the delivery wires.  So if you want 12V for example, you get exactly 12V at whatever the sense point is.

The vertical switch is for enabling or disabling the output of the power supply.  And the remaining two jacks are for test leads for the power supply's independent digital voltmeter function.

I used 12 ga for the power source wires, 18 ga for the sense wires and 22 ga for the grounds.  All the wires are silicone insulated & finely stranded so they can handle high heat and are exceptionally flexible.  They're encased in woven nylon sleeves for abrasion protection & to just keep everything tidy.

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