Hot Rod Forum : Hotrodders Bulletin Board

Hot Rod Forum : Hotrodders Bulletin Board (http://www.hotrodders.com/forum/)
-   Electrical (http://www.hotrodders.com/forum/electrical/)
-   -   Light to show fan is on (http://www.hotrodders.com/forum/light-show-fan-216298.html)

fierosum 03-08-2012 02:08 PM

Light to show fan is on
 
1 Attachment(s)
I want to know when the radiator electric fan is on. I added a small 1/8" diameter 14v bulb (looks like an LED) in parallel with the fan. See attached pic. Works great when the fan is on, the light is bright and does let me know when the fan relay kicks in at 195*F. But it illuminates about 80% when the car is moving and the temp is below 195*F. The fan acts as a generator and powers the bulb. So I added a 1N4004 diode in series with the bulb and the result was the same. I reversed the diode and the light would not come on at all. The engine is carburated not EFI. So fellas, I need someone with electrical knowledge to help me out here. Please and thank you in advance.

T-bucket23 03-08-2012 04:09 PM

Quote:

Originally Posted by fierosum
I want to know when the radiator electric fan is on. I added a small 1/8" diameter 14v bulb (looks like an LED) in parallel with the fan. See attached pic. Works great when the fan is on, the light is bright and does let me know when the fan relay kicks in at 195*F. But it illuminates about 80% when the car is moving and the temp is below 195*F. The fan acts as a generator and powers the bulb. So I added a 1N4004 diode in series with the bulb and the result was the same. I reversed the diode and the light would not come on at all. The engine is carburated not EFI. So fellas, I need someone with electrical knowledge to help me out here. Please and thank you in advance.

Feed the light power from a separate source and use the ground that gets pulled up from the relay to make the ground for the light.

vicrod 03-08-2012 04:15 PM

Connect the pilot light parallel to the coil of the relay.

vicrod

fierosum 03-08-2012 04:55 PM

The fix
 
1 Attachment(s)
Thank you for the replies. Following T-bucket23's suggestion, I connected the light bulb as per 2nd sketch. I jumper-ed the thermal switch to simulate 195* and it worked. The fan actually has enough momentum to generate the power. But I also place a house fan in front of the rad fan to simulate driving down the road and NO light. That's what makes this another great forum. Thank you fellas.


All times are GMT -6. The time now is 03:34 PM.

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0 PL2
Copyright Hotrodders.com 1999 - 2012. All Rights Reserved.