CAD CAM EDM DRO - Yahoo Group Archive

Lightbulbs and Power Resistors?

on 2003-01-10 12:15:50 UTC
Just after Thanksgiving I fired up my CNC retrofit for the first
time. I was quite excited when I ran my first G-code program on my
modified machine and watched the machine mill a ..... square.

Now I'm taking some time to:

1.) Build my power supply (original testing was done on a 6a 40v
switching supply from work). I'm building a 63 v 22 amp p/s with a
1KVA torroid I bought.

2.) Package the motor drivers, breakout board, and p/s in a nice box.


So I built my power supply and it outputs 63v. Great! Except that
once its charged, even if I shut down the p/s, I can't hookup
anything to the connector I have coming off of the capacitor unless I
creatively and safely discharge the capacitor (we all know how much
DC voltage likes to ARC). I also don't have anything but my
multimeter to tell me if the capacitor still has a charge. I tried
using a power resistor from Rad shack on the capacitor so that when
the AC power was removed the cap would discharge somewhat quicker.
However, they don't have any that are rated high enough (or I'm too
electronically challenged to know what one to buy or how to hook it
up). I also wanted to hookup 4 lightbulbs (or LEDS, I don't care) to
show me when the cap has a charge and for each of my 3 drivers to
show when power is going to the driver. The only problem with this
is that I can't find any bulbs rated for that voltage does rad shack
carry any voltage regulators for that voltage (not to mention that I
would prefer not to have to solder voltage regulators to each bulb).

Can anybody tell me what resistor to buy and how to hook it up safely
(I thought it just went across the leads of the cap, but maybe this
is wrong). Also, any ideas on how to install bulbs or LEDs to tell
me when the cap and drivers have voltage?

Thanks!

-Chris Bruno
http://www.slideruleracing.com

Discussion Thread

Chris and Dee <brunoblazer@y... 2003-01-10 12:15:50 UTC Lightbulbs and Power Resistors? Mariss Freimanis <mariss92705@y... 2003-01-10 12:45:01 UTC Re: Lightbulbs and Power Resistors? turbulatordude <davemucha@j... 2003-01-10 13:42:10 UTC Re: Lightbulbs and Power Resistors? Jon Elson 2003-01-10 22:52:04 UTC Re: [CAD_CAM_EDM_DRO] Lightbulbs and Power Resistors? turbulatordude <davemucha@j... 2003-01-11 07:16:47 UTC Re: Lightbulbs and Power Resistors? echnidna <echnidna@y... 2003-01-12 02:59:48 UTC Re: Lightbulbs and Power Resistors? turbulatordude <davemucha@j... 2003-01-12 06:59:07 UTC Re: Lightbulbs and Power Resistors? Hans Wedemeyer 2003-01-12 07:44:35 UTC Re: [CAD_CAM_EDM_DRO] Re: Lightbulbs and Power Resistors? turbulatordude <davemucha@j... 2003-01-12 08:23:17 UTC Re: Lightbulbs and Power Resistors? Tim Goldstein 2003-01-12 10:07:22 UTC RE: [CAD_CAM_EDM_DRO] Re: Lightbulbs and Power Resistors?