| Slant Six Forum https://slantsix.org/forum/ |
|
| Adjustable Voltage for Instrument Gauges https://slantsix.org/forum/viewtopic.php?t=23094 |
Page 1 of 1 |
| Author: | Jopapa [ Mon May 07, 2007 10:33 pm ] |
| Post subject: | Adjustable Voltage for Instrument Gauges |
Asking publicly so that others can benefit from the answer here  How do you go about making a adjustable voltage limiter for your instrument cluster? I'm thinking I may as well go solid state on my cluster while I'm acquiring all my aftermarket gauges... |
|
| Author: | kesteb [ Mon May 07, 2007 10:51 pm ] |
| Post subject: | |
You don't need a voltage limiter when using after market gauges. |
|
| Author: | Jopapa [ Tue May 08, 2007 5:41 am ] |
| Post subject: | |
Quote: You don't need a voltage limiter when using after market gauges.
I know. I just want it for my stock gauges since it'll probably be a little while for me to get all the aftermarket ones.
|
|
| Author: | supton [ Tue May 08, 2007 5:51 am ] |
| Post subject: | |
LM317 is a very popular part for this sort of application. Place a 240 ohm resistor between Pin 1 and pin 2, and R from Pin 2 to ground. Vout would be 1.2V + R*0.005, and taken from Pin 2. Ie, for 5V, make R equal to about 750 ohms. You can use a trimpot here, a 2k pot would probably work best, that'd get you 1.2V to about 12V. I'd use 10uF capacitors on input and output; 25V electrolytics would probably be just fine. More is better on the Vin pin (Pin 3). Just be careful: the tab is tied to Vout. Do not ground the tab! You can also do the old trick of putting diodes into the ground lead of the 7805 series of regulators. Each diode will boost the output by 0.5 to 0.7V, depending upon what diode is used (0.7 for 1N4001/related and 1N4148/1N916). You could put 1N4001/related on the output to drop voltage too. Just be careful with the diodes on the ground lead (pin 2) though: the tab is tied to pin 2 also, and you'll defeat the diodes if the heatsink is grounded also. |
|
| Author: | Jopapa [ Tue May 08, 2007 5:58 am ] |
| Post subject: | |
Quote: LM317 is a very popular part for this sort of application. Place a 240 ohm resistor between Pin 1 and pin 2, and R from Pin 2 to ground. Vout would be 1.2V + R*0.005, and taken from Pin 2. Ie, for 5V, make R equal to about 750 ohms. You can use a trimpot here, a 2k pot would probably work best, that'd get you 1.2V to about 12V.
I know a little bit about electronics, but yer still speaking Greek to me for the most part. Now my brain hurts I'd use 10uF capacitors on input and output; 25V electrolytics would probably be just fine. More is better on the Vin pin (Pin 3). Just be careful: the tab is tied to Vout. Do not ground the tab! You can also do the old trick of putting diodes into the ground lead of the 7805 series of regulators. Each diode will boost the output by 0.5 to 0.7V, depending upon what diode is used (0.7 for 1N4001/related and 1N4148/1N916). You could put 1N4001/related on the output to drop voltage too. Just be careful with the diodes on the ground lead (pin 2) though: the tab is tied to pin 2 also, and you'll defeat the diodes if the heatsink is grounded also. 
|
|
| Author: | supton [ Tue May 08, 2007 7:21 am ] |
| Post subject: | |
Sorry, it's my background... |
|
| Author: | newpoppop [ Wed May 09, 2007 5:47 pm ] |
| Post subject: | |
i'd pay someone to do it so I don't have to re-read that... LOL... |
|
| Author: | Jopapa [ Wed May 09, 2007 5:50 pm ] |
| Post subject: | |
Quote: Sorry, it's my background...
It made me cross-eyed.On the upside, now I have TWO Dusters! waitaminute... |
|
| Author: | emsvitil [ Wed May 09, 2007 6:53 pm ] |
| Post subject: | |
I understood it  (and I'm not in the field) |
|
| Author: | Jopapa [ Wed May 09, 2007 7:33 pm ] |
| Post subject: | |
Quote: I understood it
Ya may not be in the field, but you're obviously still over my head with understanding electronics (and I'm not in the field)
|
|
| Page 1 of 1 | All times are UTC-08:00 |
| Powered by phpBB® Forum Software © phpBB Limited https://www.phpbb.com/ |
|