hard start vs soft start...?? - RC Groups
Thread Tools
May 11, 2005, 04:28 PM

hard start vs soft start...??

Can someone please explain the difference between a hard start and a soft start? I'm somewhat new to RC flying and have only been doing this for a little over a year. I'm trying to figure out why my Tsunami 30A ESC only runs in contest mode.

Sign up now
to remove ads between posts
May 11, 2005, 04:45 PM
How do I land this thing?
BigShark's Avatar
I don't know that ESC, but a hard start is fine for direct drive. Soft start will power up the motor more slowly to avoid damaging a gearbox.
May 11, 2005, 05:14 PM
Registered User
Originally Posted by BigShark
I don't know that ESC, but a hard start is fine for direct drive. Soft start will power up the motor more slowly to avoid damaging a gearbox.

It will also be 'kinder' to your battery packs too......The initial power on is like a dead short across a battery pack so a soft start will be a gradual increase in load current........Its a bit like a Direct On Line(DOL) start for an industrial 3 phase motor...star/delta starters were considered soft start...

@Sharkman.....you should be able to change the esc settings...Have you got the instructions? If they appear confusing( they are not the best written...) p'rhaps we can help?
May 12, 2005, 07:15 PM
Hi Chippie,

Thanks. Yes, I do have instructions. I've been following them as best I can. My only issue right now is with getting the throttle to work after I program the ESC. That's why I want to understand the difference between a hard start and a soft start. So far, I've only been able to get the throttle to respond in mode 4 (contest mode).

I want to run the ESC in lipo mode (mode 5) since I'm using lipos, but I can't get the throttle to run the motor after I get it into mode 5. I've also tried mode 2 (motor mode) with the same results. According to the instructions, I'm in mode five because after connecting the battery with the transmitter on, I get the first beep, followed by the number of beeps for the number of lipos I programmed the ESC for, followed by the arming beep sequence. In the other modes, there are no beeps for the number of lipos programmed.

When I increase the throttle, nothing happens. What I'm not sure of and I don't see it in the instructions anywhere is what else I need to do to set the throttle after I have set the ESC to mode 5. The instructions tell me after I move the throttle to full for the number of lipos I'm using to disconnect the battery.

There is a mode 3 (heli) which the instructions mention requires a neutral setting for the throttle. I'm wondering if I am getting stuck in a neutral state somehow or if the throttle off position is getting stored backwards when I set it for mode 5. I guess I am a bit confused.

Jul 07, 2016, 03:38 PM
Top Gun
Robert Boudreau's Avatar
Could anybody help me setup a HSD 150amp ESC to soft start, it came set to soft start, somehow I changed it to hard start & it's makes the motor bang when starting. I think I cane get to startup but what to do after I enter it?

Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Hard start versus soft start electric motors Commando Sport Planes 5 Jul 09, 2016 03:40 PM
CC Phoenix 10....hard or soft start question kokamo Power Systems 5 May 21, 2005 09:57 PM
ESC hard/soft start? Will it help? Dr Kiwi Power Systems 2 Sep 08, 2004 05:02 PM
Question hard cut-off vs. soft cut-off? darrell_f Castle Creations 15 Mar 14, 2004 05:14 PM
High Start vs. E-conversion loads Sail 'n Soar Electric Sailplanes 0 Jan 20, 2003 05:49 PM