the12volt.com spacer
the12volt.com spacer
the12volt.com spacer
the12volt.com spacer
icon

what type and size resistor?


Post ReplyPost New Topic
< Prev Topic Next Topic >
bazza2468 
Member - Posts: 1
Member spacespace
Joined: April 21, 2007
Location: United Kingdom
Posted: July 29, 2007 at 11:39 AM / IP Logged  
Have a problem, I need to fool a truck into thinking the side marker lights are connected. Its a 2007 Mercedes Sprinter the side markers are 12v 3w and there are two per side. Can anyone give me some help or the formula to work out what size ballast resistor I will need to use as Iits starting to drive me crazy what type and size resistor? - Last Post -- posted image. or is it a case of use the V=IR and work it from that in which case I think I know the answer. Thanks in advance for any help.
Mad Scientists 
Silver - Posts: 380
Silver spacespace
Joined: February 07, 2004
Location: United States
Posted: July 29, 2007 at 12:30 PM / IP Logged  

Based strictly on your numbers, you'd use W=V*I, then V=I*R

3 watts = 12v * 0.25 amps (you could also measure this to verify)

12v = 0.25a *  48 ohms per bulb.

I'm guessing 4 bulbs total, for a total draw of 1 amp.. so your resistor size would have to be around 12 ohms.

12 volts = 1 amp * 12 ohms.

Now, the wattage rating of the resistor would be calculated as follows..

12 watts = 12 volts * 1 amp

So.. you'd need either (1) 12 ohm, 12 watt resistor, or (4) 48 ohm 3 watt resistors.

Pretty big resistors.

Jim 


Sorry, you can NOT post a reply.
This topic is closed.

  Printable version Printable version Post ReplyPost New Topic
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot delete your posts in this forum
You cannot edit your posts in this forum
You cannot create polls in this forum
You cannot vote in polls in this forum

  •  
Search the12volt.com
Follow the12volt.com Follow the12volt.com on Facebook
Thursday, October 31, 2024 • Copyright © 1999-2024 the12volt.com, All Rights Reserved Privacy Policy & Use of Cookies
Disclaimer: *All information on this site ( the12volt.com ) is provided "as is" without any warranty of any kind, either expressed or implied, including but not limited to fitness for a particular use. Any user assumes the entire risk as to the accuracy and use of this information. Please verify all wire colors and diagrams before applying any information.

Secured by Sectigo
the12volt.com spacer
the12volt.com spacer
the12volt.com spacer
Support the12volt.com
Top
the12volt.com spacer
the12volt.com spacer