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SJFE
04-11-2007, 09:38 AM
2 Part question. OK so I can program my 120amp esc but the hardware lacked and information when it was delivered. So who knows what the diffrence is Between a soft and hard cutoff? I assume one kills all power..the other drops voltage to a safe level for recovery. Second say yo are running 7.4 volt packs...where would you set your cut off? Even though my gusses are educated hate assuming anything..

Rex R
04-11-2007, 12:31 PM
as I understand it; the soft cut kicks in as voltage drops to a preset level under load say 3.1v per cell by limiting current(trying to keep the volts up), designed for aircraft&heli's to allow landing under power. the hard cut when cell volts drops below a 2nd lower volt point say 2.9-3.0 volts per cell(mostly we have hard cutoffs I think)
for a 2s(7.4v) it should be no lower than 6v(3 volts per cell), some say it should be 6.2volts(3.1v per cell) hth
rex

SJFE
04-11-2007, 12:36 PM
Thanks Rex. I have to toss the esc on the laptop tonight and check what settings are offered in the software. I remember seeing a soft and hard cut...but I don't think the values can be changed...I think they are all preset in a drop down.

lferguson
04-11-2007, 12:43 PM
First off I have to ask.. What ESC is it? Just curious. Second a hard cut off is, like you say, just a dead stop of power. Depending on the manufacture of the ESC, the soft cut off can be a reduced throttle power or pulses of power to the motor. I have a ESC that pulses the motor three times every 8 seconds and another that reduces full throttle power to half. For Lipos, it is SAFE to set the cutt off at 3.2V per cell. I don't care what other people say, you can not convince me otherwise! I play it safe rather than sorry and I really don't need that extra 30 seconds of runtime if it will risk my packs, which it can. So 7.4 would be a cut off at 6.4 and that would be SAFE! I have to buy my own stuff and I need it to last. I learned my leason early on about listening to "Deep Pocket Danny" or some punk ass kid who just uses daddys credit card. Play it smart

SJFE
04-11-2007, 12:54 PM
Yeah amen on that brotha..... I run a Hextronic 120. The cut off options are either or..not both. The voltage cut off options close to what you reccomend for 7.4 are 5.6, 6.0 or 7.2. I will be running 14.8 and up the max cut was 12. Looks like my best bet is leaving it to dedacated LVC.....
Thanks man

lferguson
04-11-2007, 12:59 PM
That is just me Tom, I will not set my cut off below 3.2 per cell. The Hextronix is a good ESC for the money for sure. I love mine. Water cooled it and everything. It rocks, but the USB programing thing and software are kinda screwy...But yes thats my .02

SJFE
04-11-2007, 01:06 PM
It's the one I have pictured in the Jack...ya know the water and fan cooled one...lol. My moto is anything worth doing is worth over doing.....:D