fun h bridge for winch control
in [Design]
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From: Paul Hovnanian P.E. on 8 Oct 2009 19:49 Joerg wrote: > > acannell(a)wwc.com wrote: > > On Oct 8, 6:03 am, PeterD <pet...(a)hipson.net> wrote: > >> On Wed, 7 Oct 2009 16:00:41 -0700 (PDT), "acann...(a)wwc.com" > >> > >> > >> > >> <acann...(a)wwc.com> wrote: > >>> oh you guys are gonna like this one... > >>> so i bought a winch for my jeep but it didnt come with a controller > >>> box. > >>> so i need a way to connect the 12V from the jeep battery to the winch > >>> ON and OFF like....and reverse it...so I can reverse the winch > >>> direction > >>> thats it! > >>> needs to be controlled with a rocker switch, or two switches, whatever > >>> the maximum steady-state current of the winch is about 300A, so the > >>> switching circuit needs to handle that > >>> and of course the winch is an enormous DC motor > >>> so...whats a fun way to do this? bank of mosfets? something else? > >>> i know i can just by a big relay/contactor, but i want to make this > >>> myself... > >>> suggestions? > >> Go to Warn's site, and download the schematics from one of their winch > >> controllers, they are simple, using four 'starter relays' of the Ford > >> variety, a simple switch (SPDT center off), and not much else... > >> > >> Resist the urge to go solid-state... Those 'starter relays' are about > >> $10 each at the parts store. > > > > Yeah this is probably the best idea. But I want to go solid state just > > for fun. Its a neat project dont you think? > > Fun? I don't know. But if you implement a proper PWM you could impress > your friends and tell them "Hey, I can make this huge log move at > exactly 5ft per minute" :-) That's not how things work with 4x4s. Its "Hey, I can drag my truck out of this mudhole which I had no business driving in to begin with at exactly 5ft per minute." -- Paul Hovnanian mailto:Paul(a)Hovnanian.com ------------------------------------------------------------------ I love guns. Its bullets that I can't stand.
From: Paul Hovnanian P.E. on 8 Oct 2009 19:57 Joerg wrote: > > acannell(a)wwc.com wrote: > > On Oct 8, 6:24 am, George Herold <ggher...(a)gmail.com> wrote: > >> On Oct 7, 7:00 pm, "acann...(a)wwc.com" <acann...(a)wwc.com> wrote: > >> > >> > >> > >>> oh you guys are gonna like this one... > >>> so i bought a winch for my jeep but it didnt come with a controller > >>> box. > >>> so i need a way to connect the 12V from the jeep battery to the winch > >>> ON and OFF like....and reverse it...so I can reverse the winch > >>> direction > >>> thats it! > >>> needs to be controlled with a rocker switch, or two switches, whatever > >>> the maximum steady-state current of the winch is about 300A, so the > >>> switching circuit needs to handle that > >>> and of course the winch is an enormous DC motor > >>> so...whats a fun way to do this? bank of mosfets? something else? > >>> i know i can just by a big relay/contactor, but i want to make this > >>> myself... > >>> suggestions? > >> 300 amps sems like a lot! I thought the alternator only put out 60A > >> or so? I guess they put bigger alternators in trucks and such. I've > >> got a small winch on my truck and just use a big rocker switch. > >> What's wrong with a even bigger switch? It's simple. > >> > >> George H. > > > > The battery and the alternator work together to supply the current to > > the winch.. My winch only draws 30A under no load. But under full load > > (8000lbs) draws 280A. > > > > How big of a rocker switch?? Jeez how often do you use it? Most hand > > operated switches would not be able to handle winch current. > > Well, that depends :-) > > http://www.electroswitch.com/electroswitchesandrelays/images/itapSwitch.jpg > > You can get switches rated at 1000 amps continuous. Not suitable for the application. The winch control switch is connected to the relay box with a 10 foot (or longer) cable. This way the operator doesn't have to stan next to the winch when that 5/8 inch diam cable snaps under tension. -- Paul Hovnanian mailto:Paul(a)Hovnanian.com ------------------------------------------------------------------ politics; n, from the Greek 'poly' meaning many and 'ticks', small annoying blood suckers.
From: Rich Grise on 8 Oct 2009 19:12 On Thu, 08 Oct 2009 10:47:01 -0700, acannell(a)wwc.com wrote: > On Oct 8, 6:03�am, PeterD <pet...(a)hipson.net> wrote: >> On Wed, 7 Oct 2009 16:00:41 -0700 (PDT), "acann...(a)wwc.com" >> >> >i know i can just by a big relay/contactor, but i want to make this >> >myself... >> >> >suggestions? >> >> Go to Warn's site, and download the schematics from one of their winch >> controllers, they are simple, using four 'starter relays' of the Ford >> variety, a simple switch (SPDT center off), and not much else... >> >> Resist the urge to go solid-state... Those 'starter relays' are about >> $10 each at the parts store. > > Yeah this is probably the best idea. But I want to go solid state just for > fun. Its a neat project dont you think? Well, it'll definitely be a learning experience. >:-> BTW, have you figured out the reversing thing yet? If it's a permanent magnet motor, then you just swap the poles - if it's series wound (universal), you have to swap either the armature or the field, but not both. Personally, I wouldn't bother with a solid-state controller, unless I wanted to PWM it for torque control. Good Luck! Rich
From: Rich Grise on 8 Oct 2009 19:15 On Wed, 07 Oct 2009 16:26:57 -0700, Joerg wrote: > > As you can see this gets a tad expensive. Also, you need to have some > safety shut-down feature to cut power when the MOSFETs weld themselves > shut. Or in case of a contactor if the contacts weld together. After all, > you don't want the winch to keep cranking and then pulling your Jeep up a > tree :-) Aiaiai! Shades of "The Gods Must Be Crazy." (or was that TGMBC II?) Cheers! Rich
From: George Herold on 8 Oct 2009 22:12
On Oct 8, 7:57 pm, "Paul Hovnanian P.E." <p...(a)hovnanian.com> wrote: > Joerg wrote: > > > acann...(a)wwc.com wrote: > > > On Oct 8, 6:24 am, George Herold <ggher...(a)gmail.com> wrote: > > >> On Oct 7, 7:00 pm, "acann...(a)wwc.com" <acann...(a)wwc.com> wrote: > > > >>> oh you guys are gonna like this one... > > >>> so i bought a winch for my jeep but it didnt come with a controller > > >>> box. > > >>> so i need a way to connect the 12V from the jeep battery to the winch > > >>> ON and OFF like....and reverse it...so I can reverse the winch > > >>> direction > > >>> thats it! > > >>> needs to be controlled with a rocker switch, or two switches, whatever > > >>> the maximum steady-state current of the winch is about 300A, so the > > >>> switching circuit needs to handle that > > >>> and of course the winch is an enormous DC motor > > >>> so...whats a fun way to do this? bank of mosfets? something else? > > >>> i know i can just by a big relay/contactor, but i want to make this > > >>> myself... > > >>> suggestions? > > >> 300 amps sems like a lot! I thought the alternator only put out 60A > > >> or so? I guess they put bigger alternators in trucks and such. I've > > >> got a small winch on my truck and just use a big rocker switch. > > >> What's wrong with a even bigger switch? It's simple. > > > >> George H. > > > > The battery and the alternator work together to supply the current to > > > the winch.. My winch only draws 30A under no load. But under full load > > > (8000lbs) draws 280A. > > > > How big of a rocker switch?? Jeez how often do you use it? Most hand > > > operated switches would not be able to handle winch current. > > > Well, that depends :-) > > >http://www.electroswitch.com/electroswitchesandrelays/images/itapSwit... > > > You can get switches rated at 1000 amps continuous. > > Not suitable for the application. The winch control switch is connected > to the relay box with a 10 foot (or longer) cable. This way the operator > doesn't have to stan next to the winch when that 5/8 inch diam cable > snaps under tension. > > -- > Paul Hovnanian mailto:P...(a)Hovnanian.com > ------------------------------------------------------------------ > politics; n, from the Greek 'poly' meaning many and 'ticks', small > annoying blood suckers.- Hide quoted text - > > - Show quoted text - Mind if I ask another 'stupid' question? What gauge of cable do you use to run to the box? I've got a left over hunk of 12 gauge that runs to the rocker switch (60A max, maybe 5 feet of cable). Ahhh the light begins to dawn. You have to mount the switch on the motor. What are you going to do about water? George H. |