Go Back   EcoModder Forum > EcoModding > DIY / How-to
Register Now
 Register Now

Reply  Post New Thread
Submit Tools LinkBack Thread Tools
Old 10-10-2011, 06:07 AM   #1 (permalink)
EcoModding Apprentice
Join Date: Mar 2011
Location: alaska
Posts: 141
Thanks: 10
Thanked 32 Times in 18 Posts
latching relay to add "electric start" to EV?

i'm converting a snowmobile from internal combustion to electric power, and one of the rules is:

Snowmobiles in this competition will be operated by judges familiar with the operation of snowmobiles. For this reason, the Zero Emissions snowmobile must be turned on and off like a conventional electric start internal combustions snowmobile.
The ZE snowmobile must have a key operation with OFF, ON, and CRANK positions. In the OFF position the snowmobile will be de-energized (contactors open) and not move when the thumb actuated throttle is moved. In the ON position, the snowmobile’s low voltage systems may be enabled, however the high voltage system must remain de-energized until the key is cranked. In the momentary CRANK position, high voltage is enabled. A green LED light labeled VEHICLE READY will be illuminated and must remain illuminated until the vehicle is shutdown or high voltage is disabled. An example of a possible state machine representation of this is shown below

any ideas as to the best way to do this?

i think i can do it with two relays in series, where the "run" position closes the first relay. the second relay would get it's coil voltage from the momentary "start" position, but then have a Y so it can also receive power from the switched side of its own contacts. when the key is turned off it will kill the first relay, cutting the circuit, and killing the second relay.

any reasons this shouldn't work? or is there a better way?

open to suggestions

Last edited by isaac_alaska; 10-10-2011 at 06:28 AM..
  Reply With Quote
Alt Today
Popular topics

Other popular topics in this forum...

Old 10-10-2011, 08:44 AM   #2 (permalink)
Master EcoModder
Ryland's Avatar
Join Date: Jan 2008
Location: Western Wisconsin
Posts: 3,903

honda cb125 - '74 Honda CB 125 S1
90 day: 79.71 mpg (US)

green wedge - '81 Commuter Vehicles Inc. Commuti-Car

Blue VX - '93 Honda Civic VX
Thanks: 867
Thanked 433 Times in 353 Posts
latching relay wiring diagram - Google Search
  Reply With Quote
Old 11-30-2011, 10:12 PM   #3 (permalink)
Lurking Around
Impulse's Avatar
Join Date: Jun 2008
Location: Nova Scotia, Canada
Posts: 39

96 Civic - '96 Honda Civic CX
Team Honda
90 day: 33.2 mpg (US)

09 Sierra - '09 GMC Sierra SLE
90 day: 19.76 mpg (US)

09 Matrix - '09 Toyota Matrix XR
90 day: 25.22 mpg (US)
Thanks: 13
Thanked 1 Time in 1 Post
First here is a latching relay diagram that I think would work for you, the positive pulse from alram input would actually be your momentary start output from the key switch.

Second, as there are so many ways for you to wire this up check out Relay Diagrams - Quick Reference This is a huge resource of information that should help you figure out what you want to do
  Reply With Quote
Old 11-30-2011, 10:34 PM   #4 (permalink)
EcoModding Apprentice
Join Date: Mar 2011
Location: alaska
Posts: 141
Thanks: 10
Thanked 32 Times in 18 Posts
Impulse, that's exactly the diagram I had planned In my head! So I guess it will probably work now I need to find a box that holds a bunch of 12v relays good for 10 amps or so... Ev source has a nice one I will probably buy

  Reply With Quote
Reply  Post New Thread

Thread Tools

Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2021, vBulletin Solutions Inc.
Content Relevant URLs by vBSEO 3.5.2
All content copyright EcoModder.com