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Old 09-01-2010, 12:41 AM   #1
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Default tekin rx8 cutting in and out help

hey guys i have a tekin rx8 setup in a losi xxl running a 2000kv motor 63spur 25 pinion 4s 5000mah lipo and dx3s radio.

I have set the exc up using the hotwire interface on my comp. i set the low voltage cutoff to 3.115 volt per cell. when using the truck it will just stop, i will still have steering but no brakes for forwards. the lights on the speedy still light up from 1 to 7 as you increase throttle but nothing happens.

I am not sure if its hitting the lipo cut off but when i put the battery on my chargers it says its still at about 3.7 to 3.8v per cell still. if i put the battery in my 8ight truggy with mamba setup low voltage cutoff set to 3.1v per cell i get about another 5-7 mins run time.

anyone got any ideas
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Old 09-01-2010, 08:06 AM   #2
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When the Rx8 goes into lipo cut off it will show you on the led's. When your car stops you need to look at the 7 led's and see which ones are lit.

Understand that with the lvc custom settings you need to set it to the TOTAL voltage not "per cell."

You need to see the led sequence when it stops.
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Old 09-04-2010, 05:22 PM   #3
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When the Rx8 goes into lipo cut off it will show you on the led's. When your car stops you need to look at the 7 led's and see which ones are lit.

Understand that with the lvc custom settings you need to set it to the TOTAL voltage not "per cell."

You need to see the led sequence when it stops.
hey randy,

so with the lvc setting are you saying if you use 4s and 5s lipos you need to change the setting each time to suit which battery you are using? if so i guess i should decide which one to use and set it to that and keep it there?

As to the cutting out i will try a couple of packs today and let you know what leds are lit when it stops.
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Old 09-04-2010, 05:38 PM   #4
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hey randy,

so with the lvc setting are you saying if you use 4s and 5s lipos you need to change the setting each time to suit which battery you are using? if so i guess i should decide which one to use and set it to that and keep it there?

As to the cutting out i will try a couple of packs today and let you know what leds are lit when it stops.

Correct,
you would use a different custom lvc for 4s vs 5s

The lvc that you set is for total pack voltage.

Dayton
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Old 09-04-2010, 07:15 PM   #5
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hey randy,

so with the lvc setting are you saying if you use 4s and 5s lipos you need to change the setting each time to suit which battery you are using? if so i guess i should decide which one to use and set it to that and keep it there?

As to the cutting out i will try a couple of packs today and let you know what leds are lit when it stops.

okay randy,

have been out for a bash it all started good. then it stopped i think the leds were number 2 on then a quick flash of 4 and 5. i am not sure of this as i didn't get a good look before it worked again. i believe when the unit is working it will flash #1 then either 1 12 123 1234 to indecate temp. it only ever got to 123. Now it got the point when it just stopped and wouldn't go again i was using a 5s the charger said it was at 3.67vpc the leds were showing 1 then a flash to 4 but it wouldn't do anything other than steer. I put a partly charged 4s on it the same leds were lit and it worked i put the 5s back on it and the same leds again but still no work.
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Old 09-04-2010, 09:05 PM   #6
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If it worked after swapping the 5s for the 4s sounds like a battery issue. If one cell is dropping voltage while under a load this can causse LVC.

A quick "check" to verify this is once it stops. Use the onboard buttons and turn your VC to led 1(off). If it drives again you've found the issue.
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Old 09-05-2010, 02:48 AM   #7
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If it worked after swapping the 5s for the 4s sounds like a battery issue. If one cell is dropping voltage while under a load this can causse LVC.

A quick "check" to verify this is once it stops. Use the onboard buttons and turn your VC to led 1(off). If it drives again you've found the issue.
hey randy

i will do the check you are talking about in a minute. but the other day when i was using a friends a hotwire i set the cutoff to 1.15 thinking it was percell not overall meaning it can't really be the battery.

it has done this with 3 different packs i have all seem to say around 3.6-3.7 percell on the charger when they stop in the truck.
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Old 09-05-2010, 10:19 AM   #8
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On the Rx8/Hotwire you must set the "Total" voltage you want the cut off to activate at.
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Old 09-05-2010, 06:05 PM   #9
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On the Rx8/Hotwire you must set the "Total" voltage you want the cut off to activate at.
okay i set the lvc to a 5s just using the unit itself. it ran fairly well but after a little flip it stopped but then after 10 secs or so it went again.

i then just held the back and made it spin wheels changing from low to high throttle after a short time it cut out. the leds were showing 4 on and qucik flash to 123 just showing the temp. if i tried to apply throttle the leds would ramp up like their meant to but nothing would happen there has to be something wrong with this. i drove it in the house last night just slowly which doesn't normally make it cut out until it stopped from lvc it showed leds 135 as it should.

so when it cuts out on the street its not the lvc any other ideas
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Old 09-05-2010, 08:11 PM   #10
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Does this unit have 4 holes in the bottom or 3?
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Old 09-06-2010, 04:08 AM   #11
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Does this unit have 4 holes in the bottom or 3?
hey randy it has 4 holes in the bottom hope that helps.
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Old 09-06-2010, 08:41 AM   #12
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Then I'd reccomend sending it in. It doesn't have the latest case and really needs to get it.

Contact me or contact support for an RA#: [email protected], or [email protected]
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