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-   -   Voltage Cutoff in a Starter Box (https://www.rctech.net/forum/nitro-off-road/327833-voltage-cutoff-starter-box.html)

khudzik 09-15-2009 10:02 AM

Voltage Cutoff in a Starter Box
 
Been trying to find if anyone ever actually wired a low voltage cutoff into a starter box. So far couldn't find anything except for opinions that you probably don't need it. So I guess the question still stands, has anyone ever done it? If so, could you post a wiring diagram? Thanks.

Integra 09-15-2009 02:29 PM


Originally Posted by khudzik (Post 6348334)
Been trying to find if anyone ever actually wired a low voltage cutoff into a starter box. So far couldn't find anything except for opinions that you probably don't need it. So I guess the question still stands, has anyone ever done it? If so, could you post a wiring diagram? Thanks.



you dont "NEED" a cut off on a starter box really....as long as you dont run it for a month strait and expect it to start a stubborn motor tank after tank after tank.....pending on the Mah you CAN go multiple race days on a single charge....but other thing's will factor in....does your motor start with little effort....or do you have to ram it multiple time's to get it to fire.......If there's anything that i would recommend running as a backup for a lipo on starter box duties would be a lipo Monitor(link below) basically it monitor's the cell's voltage and know's when you need to charge it and it will audibly warn you as well as LED's to tell you the status of the pack...there Cheap insurance...i run one in my box. :nod:

http://cgi.ebay.com/Maxpro-4S-Lipo-B...d=p3286.c0.m14

OfnaJoe 09-15-2009 02:32 PM

That's about like the one I got from ebay, has not arrived yet but it's just for extra protection.

Integra 09-15-2009 02:40 PM

they are worth their weight in gold if you ask me....its saved a couple buddy's lipo's from puffage :lol:

If you want to be real safe about it....Charge the pack After Every day event and monitor how many Mah the pack take's....and remember roughly how many time's you started your car...then factor that into a full weekend of running...you should be able to figure out if you'll need to recharge before the Sunday A-main's.

OfnaJoe 09-15-2009 02:46 PM

I just charged my 2200 4S pack and it took 497 mah and I started the car 10 times, I think I charged it before the day started:confused:

houston 09-15-2009 03:02 PM


Originally Posted by OfnaJoe (Post 6349460)
I just charged my 2200 4S pack and it took 497 mah and I started the car 10 times, I think I charged it before the day started:confused:

:weird: wow , super cool 49.7 Mah each start


i still want a cutoff in my starter box so who makes the cutoff :confused:

houston 09-15-2009 03:03 PM


Originally Posted by OfnaJoe (Post 6349460)
I just charged my 2200 4S pack and it took 497 mah and I started the car 10 times, I think I charged it before the day started:confused:

and hows the engine ? :D

Razathorn 09-15-2009 03:09 PM

I use two $9 1500 mah nicads 7.2 packs. I charge them perhaps once every two to three race nights. I didn't realize this was a problem that needed solving still.

devilchrist 09-15-2009 03:09 PM

what if you absolutly need to start the engine but your cut of won't let you?

why not a monitor

I run a voltage monitor that's hard wired on the starterbox wiring.
solid blue when full charge
blinking blue when 3.9+
blinking red when 3.7+
solid red when 3.4+
beeping and solid red when 3.1

i have 2 2650 mah packs in the box, switch to other fresh one when it gets to blinking red.

bentgear 09-15-2009 03:11 PM

To actually have a cutoff would mean you would have to pass the curent thru some type circuit that could be over ridden when the voltage got low. Cost would most likely equal the price of the battery pack. Charge fairly often or get a voltage monitor.

A 2,000 pack should last for weeks if:
1. the engine starts quickly
2. the starter box motor, belts and wheel is in good shape
3. everything is lined up so the starter wheel is ONLY touchng the flywheel.

Most of the people that call their starter box junk can't get items 1 and/or 3 right.

houston 09-15-2009 03:11 PM


Originally Posted by devilchrist (Post 6349546)
what if you absolutly need to start the engine but your cut of won't let you?

why not a monitor

I run a voltage monitor that's hard wired on the starterbox wiring.
solid blue when full charge
blinking blue when 3.9+
blinking red when 3.7+
solid red when 3.4+
beeping and solid red when 3.1

i have 2 2650 mah packs in the box, switch to other fresh one when it gets to blinking red.

there are lipo accidents ;)

and because even when heated a new engine can take a bit to fire off

and i do alot of engine break ins , wore the truggy box down in about an hour before


who makes the lipo cutoff for 14.8v pack ?

OfnaJoe 09-15-2009 03:13 PM


Originally Posted by houston (Post 6349523)
and hows the engine ? :D

GREAT, WOWIE, YIPEEE, REALLY REALLY GOOD:nod::nod:
And Congrats on your RCPRO finishes way to go, seen the pics that Rev posted on Nitro addicts, and this is the cut-off\alarm I got coming:
http://cgi.ebay.com/ws/eBayISAPI.dll...=STRK:MEWNX:IT

Integra 09-15-2009 04:05 PM

houston dont bother with a cut off....the monitor's are more then enough...and if your still scared then get a 5000mah 4 cell for 80$ from Hobby king and Forget about charging every week. :lol:

Frank L 09-15-2009 04:38 PM

I was concerned at 1st when I switched to lipo and now after using lipo for 6 months I am not concerned at all anymore I will charge the night before race day and theres no prob. I have even let it go 2 days when I go to 2 day events and no prob at all. I use losi lipos so I dont want to lose one but so far no need to use a cut off. Running a buggy and truggy now and one lipo is all I need for the day. I cary a backup just in case you never know. I had the old losi box take a dump, heat up and try to short out a lipo, drained it down to 11.5 volts, way to low for a 4 cel, and charged it back up no problems. Been using the same lipo that dumped for 6 months now. I love these lipos. I started using them in the receiver packs too and theres no need for a cut off just change after every race day, they arent even 1/2 used. Why install another component that can fail and cause a dnf.

Integra 09-15-2009 04:54 PM

Frank do you "store" your packs...or re-peak and leave them till the next race day ?


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