Go Back   EcoModder Forum > EcoModding > Motorcycles / Scooters
Register Now
 Register Now
 

Reply  Post New Thread
 
Submit Tools LinkBack Thread Tools
Old 03-27-2011, 02:22 AM   #1 (permalink)
EcoModding Lurker
 
Join Date: Mar 2011
Location: California
Posts: 1
Thanks: 0
Thanked 0 Times in 0 Posts
Precharging and Closing solenoid using RFID ignition system

So I'm almost finished converting my motorcycle to all electric. I am using a DC solenoid in between the controller (an Alltrax AXE 4844) and the battery ground. I already have written up an RFID recognition program for the Arduino. So when i swipe the correct card across the antenna the Arduino attempts to recognize whether or not the it is the correct card, and then it blinks a green or red LED accordingly. Once the correct card is swiped I have a digital I/O pin write high to switch on an N type mosfet, similar to the TIP220. When the mosfet closes it completes the 12v circuit across the coil of the solenoid causing the solenoid to close and the full 48v to run across the main contacts and straight into the controller.

Now, across these main contacts i have a precharge resistor. its purpose is to precharge the large capacitors in the controller and prevent them from being damaged by the large influx of current and voltage when the solenoid closes. But this resistor is always allowing (a relatively small) voltage across it, therefore draining the battery. In order to prolong battery life I want to be able to turn off this resistor when the bike is parked. I have tried doing it by running it through another transistor. And changed the code to turn that precharge transistor on first, wait a certain amount of time, and then power up the other main transistor. But when the precharge resistor should be on, nothing happens. Is it because the precharge resistor has no specific polarity and therefore isn't ever in contact with the positive wire? Or am i going to have the transistor turn on another, smaller, relay? Help would be greatly appreciated.



Check out the rest of the build at: payneev.com


Last edited by majorpayne; 03-27-2011 at 02:28 AM..
  Reply With Quote
Alt Today
Popular topics

Other popular topics in this forum...

   
Old 03-28-2011, 04:20 AM   #2 (permalink)
EcoModding Apprentice
 
Join Date: Aug 2009
Location: London, UK
Posts: 113
Thanks: 16
Thanked 3 Times in 3 Posts
I've found

Forum for Electronics

a useful site for electronics.

  Reply With Quote
Reply  Post New Thread


Tags
arduino, mosfet, precharge, relay, solenoid

Thread Tools




Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2020, vBulletin Solutions Inc.
Content Relevant URLs by vBSEO 3.5.2
All content copyright EcoModder.com