DIYbio:Notebook/Open Gel Box 2.0/Power Supply
Jan 08, 2009, 10:34 PM
Specification Discussion
After talking to a number of people and reading the various discussion threads I propose the following specification for the Power Supply.
Edit each line to place a y (agree) or an n (disagree) for each of the line items. You do not need to justify any n's.
Feel free to add a line item you feel is important.
When all interested parties have had their "vote" we'll revisit and discuss any that have too many n's.
- Must be totally enclosed (y)(y)
- Must work with 110/220 VAC input (y)(y)
- Must work with 50Hz/60Hz AC input (y)
- Single channel 20-120 VDC output voltage, variable in 10 V steps (y)(y, at least)
- Must use red and black banana plug connectors (y)(y)
- Must have a voltmeter display (y)(y)
- Must be capable of continuous 300 mA load (y)(y, at least)
- Must employ resettable CB protection (y)
Jan 06, 2009
What we need: clean, stable, variable DC at 20V-100V, adjustable (possibly up to 600V).
Consider: using a cheap computer ATX supply feeding a voltage regulator such as an LM317 feeding a DC/DC step-up built on the model introduced in http://www.edn.com/contents/images/70804di.pdf (from http://www.edn.com/article/CA431146.html ).
For $10-$20 , you get plenty of overhead (i.e. 400W max neighborhood), 50/60Hz and 110/220V independence, amp draw regulation (probably? not sure what typical protection is in the low price range), and handy plug-in molex connectors. The last point is particularly salient, if you can power more than one device with a versatile power supply.
- Low cost "brick" supply is available from manufacturers such as GlobTek (Taiwan); *jcline@ieee.org 18:22, 8 January 2009 (EST):
- For example, GT(M)21097CC SERIES 50W
- "AC/DC LOW-VOLTAGE SINGLE-OUTPUT, CONSTANT-CURRENT, VOLTAGE-LIMITED SWITCHING POWER SUPPLIES(DESKTOP), UNIVERSALINPUT/IEC 320 INPUT RECEPTACLE FOR CONNECTION OF POWER SUPLYCORD SET, INTENDED FOR USE WITHIN INFORMATION TECHNOLOGYEQUIPMENTAND MEDICALELECTRICAL EQUIPMENT."
- Has Input Voltage 90v-260v @ 47Hz-63Hz (suitable for worldwide use)
- Has Output Voltage +48.0 VDC @ 0 - 1.1 A
- Cost is probably around $20-$30 per unit in low quantities.
I do not know how adding a voltage regulator (LM317 etc) and DC/DC step-ups after these affect their voltage regulating properties.
Converting a computer ATX power supply to a really useful lab power supply http://www.instructables.com/id/Converting-a-computer-ATX-power-supply-to-a-really/
How to Add Variable Voltage to Your ATX Based Bench Power Supply http://www.wikihow.com/Add-Variable-Voltage-to-Your-ATX-Based-Bench-Power-Supply
Building a Power Supply http://www.eleinmec.com/article.asp?16
