Go Back  R/C Tech Forums > General Forums > Nitro Off-Road
what lipo for ofna truggy starter box? >

what lipo for ofna truggy starter box?

what lipo for ofna truggy starter box?

Old 02-22-2011, 04:26 PM
  #31  
Tech Regular
iTrader: (6)
 
bre1979's Avatar
 
Join Date: Mar 2008
Location: Pasco, WA.
Posts: 337
Trader Rating: 6 (100%+)
Default

I have to do this to my box.
bre1979 is offline  
Old 02-22-2011, 06:40 PM
  #32  
Tech Lord
iTrader: (8)
 
Integra's Avatar
 
Join Date: Dec 2006
Posts: 12,489
Trader Rating: 8 (100%+)
Default

Originally Posted by teeforb
how is it using 5S compared to 4S?


seeing as our motor's in our boxes are rated up to 18volts, I would guess your box will be a bit more powerful and might have a slightly shorter life span for the fact a 5S is a Hair over 18volts. But like anything electrical If you take care of it and Dont try and Force start a motor that's Locked at TDC or Bottoming out on the chassis you should be good to go for years to come.
Integra is offline  
Old 02-23-2011, 06:09 AM
  #33  
Tech Rookie
 
Join Date: Feb 2011
Location: Porto, Portugal
Posts: 13
Default

Originally Posted by teeforb
i would think it's max by amps and voltage. Like a 12v 30AMP relay or a 1v .5Amp relay. I believe a relay is just some bjt, Darlington pairs, or some kink of high amp transistors. Therefore, specs are important.

and there's SPDT (single pole double throw) and SPST (single pole single throw)...
I'm using a 12V/40A SPST, you could use a SPST or SPDT as long as you use the normally open contact

A relay is a simple electromechanical device, there is no bjt, Darlington pairs, or some kink of high amp transistors in there.

To save the "life" of the relay contact I use a capacitor of 40V/3000uF in parallel to the coil, this way you avoid the short-cycles that would eventually kill the contact .
BiteTheBullet is offline  
Old 02-23-2011, 06:23 AM
  #34  
Tech Master
iTrader: (2)
 
Join Date: Jan 2009
Posts: 1,780
Trader Rating: 2 (100%+)
Default

Wiring diagram anyone?
ganymede is offline  
Old 02-23-2011, 07:38 AM
  #35  
Tech Champion
Thread Starter
iTrader: (94)
 
teeforb's Avatar
 
Join Date: Sep 2005
Location: San Diego & Compton CA
Posts: 7,261
Trader Rating: 94 (100%+)
Default

Originally Posted by BiteTheBullet
I'm using a 12V/40A SPST, you could use a SPST or SPDT as long as you use the normally open contact

A relay is a simple electromechanical device, there is no bjt, Darlington pairs, or some kink of high amp transistors in there.

To save the "life" of the relay contact I use a capacitor of 40V/3000uF in parallel to the coil, this way you avoid the short-cycles that would eventually kill the contact .
Can u elaborate on short cycle?
teeforb is offline  
Old 02-23-2011, 08:05 AM
  #36  
Tech Champion
Thread Starter
iTrader: (94)
 
teeforb's Avatar
 
Join Date: Sep 2005
Location: San Diego & Compton CA
Posts: 7,261
Trader Rating: 94 (100%+)
Default

here is a good page...

http://www.mp3car.com/the-faq-empori...ire-it-up.html
teeforb is offline  
Old 02-23-2011, 09:12 AM
  #37  
Tech Champion
Thread Starter
iTrader: (94)
 
teeforb's Avatar
 
Join Date: Sep 2005
Location: San Diego & Compton CA
Posts: 7,261
Trader Rating: 94 (100%+)
Default

Got a 30amp relay. Is that big enough?
teeforb is offline  
Old 02-23-2011, 09:30 AM
  #38  
Tech Master
iTrader: (31)
 
trickedout's Avatar
 
Join Date: Jun 2009
Location: Las Vegas/Pahrump,NV
Posts: 1,273
Trader Rating: 31 (100%+)
Default

Originally Posted by teeforb
Great little read there for those unfamiliar with relays. Yes a 12v 30a relay should be just fine
trickedout is offline  
Old 02-23-2011, 10:02 AM
  #39  
Tech Champion
Thread Starter
iTrader: (94)
 
teeforb's Avatar
 
Join Date: Sep 2005
Location: San Diego & Compton CA
Posts: 7,261
Trader Rating: 94 (100%+)
Default

in regards of hooking it up...

pin 85 --------> lipo gnd
lipo pos --------> starter box switch ____/ ____ ---------> pin 86
lipo pos ---------> pin 30
pin 87 ----------> + on Motor
lipo gnd -----------> gnd of motor

is this correct?
teeforb is offline  
Old 02-23-2011, 11:06 AM
  #40  
Tech Master
iTrader: (31)
 
trickedout's Avatar
 
Join Date: Jun 2009
Location: Las Vegas/Pahrump,NV
Posts: 1,273
Trader Rating: 31 (100%+)
Default

Originally Posted by teeforb
in regards of hooking it up...

pin 85 --------> lipo gnd
lipo pos --------> starter box switch ____/ ____ ---------> pin 86
lipo pos ---------> pin 30
pin 87 ----------> + on Motor
lipo gnd -----------> gnd of motor

is this correct?
Yes i believe that looks correct, if you plan to keep your Switch, if not pin 86 will hook up straight to the contact spring when you push the car down...Having the switch just breaks that connection when not on.
trickedout is offline  
Old 02-23-2011, 01:43 PM
  #41  
Tech Rookie
 
Join Date: Feb 2011
Location: Porto, Portugal
Posts: 13
Default

Originally Posted by teeforb
in regards of hooking it up...

pin 85 --------> lipo gnd
lipo pos --------> starter box switch ____/ ____ ---------> pin 86
lipo pos ---------> pin 30
pin 87 ----------> + on Motor
lipo gnd -----------> gnd of motor

is this correct?
I'm going to post here the link for the circuit and a photo of my installation, post them here if you wish:

h ttp://img64.imageshack.us/img64/7646/circuitocaixaus.jpg

h ttp://img27.imageshack.us/img27/8859/caixa1.jpg

About short-cycle, if you press the car in the box and for an instant you let the switch go off and them press the car again, your are wearing the relay contact, if you look at the graph you will see that the switch was let of in the instants t1, t2 and t3, but the motor keeps spinning avoiding the relay to open and close for 3 times. Is it clear?
BiteTheBullet is offline  
Old 02-23-2011, 02:29 PM
  #42  
Tech Champion
Thread Starter
iTrader: (94)
 
teeforb's Avatar
 
Join Date: Sep 2005
Location: San Diego & Compton CA
Posts: 7,261
Trader Rating: 94 (100%+)
Default

Originally Posted by BiteTheBullet
I'm going to post here the link for the circuit and a photo of my installation, post them here if you wish:

h ttp://img64.imageshack.us/img64/7646/circuitocaixaus.jpg

h ttp://img27.imageshack.us/img27/8859/caixa1.jpg

About short-cycle, if you press the car in the box and for an instant you let the switch go off and them press the car again, your are wearing the relay contact, if you look at the graph you will see that the switch was let of in the instants t1, t2 and t3, but the motor keeps spinning avoiding the relay to open and close for 3 times. Is it clear?
so you prevent on/off cycles when pressing down on the box, by storing charge in the cap. once u let off the box for T=t, the cap discharges and the relay opens.
teeforb is offline  
Old 02-23-2011, 09:08 PM
  #43  
Tech Champion
Thread Starter
iTrader: (94)
 
teeforb's Avatar
 
Join Date: Sep 2005
Location: San Diego & Compton CA
Posts: 7,261
Trader Rating: 94 (100%+)
Default

I hooked up the relay with the cap. I only found a 4700 micro F. I think that was go big. It's a 1.5sec delay in the spin. Hope it won't be a big deal for starting. This mod is a good idea! Esp the cap part. Thanks all for the info. Sharing is caring, is what my 3 year old daughter always tell me!
teeforb is offline  
Old 02-23-2011, 11:39 PM
  #44  
Tech Master
iTrader: (2)
 
Join Date: Jan 2009
Posts: 1,780
Trader Rating: 2 (100%+)
Default

Can someone point out how do you wire the relay and the capacitor with a wiring diagram like this? Thanks in advance!

Just noticed these two wiring diagram are a bit different, any pointers?



Last edited by ganymede; 02-23-2011 at 11:53 PM.
ganymede is offline  
Old 02-24-2011, 06:01 AM
  #45  
Tech Master
iTrader: (8)
 
Gary NJ's Avatar
 
Join Date: Jan 2004
Location: Long Island NY
Posts: 1,157
Trader Rating: 8 (100%+)
Default

Originally Posted by Integra
seeing as our motor's in our boxes are rated up to 18volts, I would guess your box will be a bit more powerful and might have a slightly shorter life span for the fact a 5S is a Hair over 18volts. But like anything electrical If you take care of it and Dont try and Force start a motor that's Locked at TDC or Bottoming out on the chassis you should be good to go for years to come.
Sorry, didn't get back to this thread after I posted earlier. Integra covered it all. The motor certainly spins harder on 5S....

I was thinking about doing a GMK Supply 12V relay upgrade kit for boxes for a year now...this thread may finally get me off my ass to do it!
Gary NJ is offline  

Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service -

Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.