Anybody have any ideas on what would cause the controller to go into fault mode shortly after it is turned on. Supposedly the circuit in the blanket is the...
58160
proto_specialist
proto_specia...
Jan 3, 2010 4:41 am
Hi Ken, I'm no expert with SCRs, having only used them in one design, and that was years ago. However, I believe the normal way of turning off an SCR involves...
58159
hrh1818
Jan 3, 2010 3:18 am
... Correction the tank capacitors were rated at 900 VAC. Howard...
58158
Mike Payson
mpayson
Jan 3, 2010 3:08 am
I've never used one, but the other way is to use a "bed of nails". Basically, use a conductive pin that connects to each test point, one for each point. Simply...
58157
Howard Hansen
hrh1818
Jan 3, 2010 1:36 am
Orville here is a link to a DIY Tig welder. http://www.cnczone.com/forums/showthread.php?t=21978 About 1/2 down the page is a link to a schematic diagram. This...
58156
blue_eagle74
Jan 3, 2010 1:11 am
At work we have a flying probe. it takes the pcb date and does checks for shorts, opens, checks resistors, caps. It is expensive but worth it. Do a search for...
58155
orvillefpike
Jan 2, 2010 8:59 pm
Here is a link to that schematic. ...
58154
Nuno T.
nuno_tv
Jan 2, 2010 8:46 pm
... The gate circuits that use a NPN on that book do so to turn on the SCR, not off. ... Removing the gate signal will not turn off the SCR if it's working on...
58153
Howard Hansen
hrh1818
Jan 2, 2010 8:09 pm
Could you post a diagram of your arc starter circuit in files folder for this group? Howard...
58152
orvillefpike
Jan 2, 2010 7:50 pm
I could try to make a capacitor the way M. Popelish suggested but if I can put a bunch of capacitors together, at least to experiment, it might be easier for...
58151
orvillefpike
Jan 2, 2010 7:44 pm
Exactly....
58150
Howard Hansen
hrh1818
Jan 2, 2010 6:19 pm
Are you trying to make a RF arc starter for a TIG welder without the electrode touching the 2work? Howard...
58149
sailingto
Jan 2, 2010 5:39 pm
Thank you for the link to the Philips book - I've downloaded and read thru pages from 497 thru the next several pages. It looks like the NPN transistor I...
58148
Bob Huish
bobhuish2003
Jan 2, 2010 4:07 pm
Hi I have a few NEW GE SCRs that are 100 amp. #11253808 7035A c152nr61. I can't find anything on the web about them, but if you PM me your addr I will send 4...
58147
Reese
reeza
Jan 2, 2010 3:57 pm
... These are likely torx screws, they require a torx driver bit. If there is a pin in the middle of the "star" to prevent insertion of a torx driver unless...
58146
orvillefpike
Jan 2, 2010 3:50 pm
I want to make an arc starter for an arc welder and I need a capacitor capable of handling 12 kV....
58145
Nuno T.
nuno_tv
Jan 2, 2010 11:44 am
... Not sure if I understood you corretly. You want to turn OFF a SCR by turning off the signal gate? I advise you to read this book (pg 497 or so...) It has...
58144
Leon Heller
leon_heller
Jan 2, 2010 11:30 am
... From: "sanmeeth"; <sanmeeth@...> To: <Electronics_101@yahoogroups.com> Sent: Saturday, January 02, 2010 9:58 AM Subject: [Electronics_101] Testing...
58143
greatyoga
Jan 2, 2010 10:01 am
Thanks Steve and to all who responded. I saw the one video before that has a hole near the door of the DVD player. However, my player does not have a hole....
58142
sanmeeth
Jan 2, 2010 10:00 am
Hi What is the correct way to test PCBs by incoming Quality assurance section. We are verifying the PCBs visually using a multimeter and a schematic copy to...
58141
sailingto
Jan 2, 2010 4:08 am
Hello, I have several TNY640 SCR devices rated at 40amp each. I would like to use these power a 100 amp power supply with max voltage at 13.8vdc. My desire...
58140
Howard Hansen
hrh1818
Jan 2, 2010 4:07 am
What type of application do you have in the back of your mind? Most high voltage power supply in the 15 kilovolt range only need to supply milliamps or less of...
58139
Ross McKenzie
ross_valusoft
Jan 2, 2010 3:03 am
... Yes but ... you should never be operating that close to the rated voltage. I like to have at a least a 25% headroom margin and preferably 50%. Cheers, Ross...
58138
orvillefpike
Jan 2, 2010 2:55 am
M. Mead, What do you mean by "as long as the caps can holdoff the current"? Thanks...
58137
orvillefpike
Jan 2, 2010 2:39 am
What worries me is, will all the capacitors have the same voltage across them, even if they are the all the same, because if the ESR varies, some of them might...
58136
Frank Mead
fmead
Jan 1, 2010 6:22 pm
No...as long as the caps can holdoff the current. ... [Non-text portions of this message have been removed]...
58135
Howard Hansen
hrh1818
Jan 1, 2010 5:35 pm
The big problem with putting capacitors in series is you are effectively reducing the total capacitance. If you put two 2,000pf capacitors in series the series...
58134
orvillefpike
Jan 1, 2010 4:14 pm
Is it a problem to put a bunch of high voltage capacitor (1,000V) in serie?...
58133
dave_mucha
Jan 1, 2010 3:31 pm
use any of the free schematic layout software packages. ultimatly, it will give you a layout that you can use to move wires. just move them as if they were...
58132
Leon Heller
leon_heller
Jan 1, 2010 1:21 pm
... From: "riverrat373" <mdc002@...> To: <Electronics_101@yahoogroups.com> Sent: Friday, January 01, 2010 12:31 AM Subject: [Electronics_101] Reading...
