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Remote Battery Disconnect

14K views 17 replies 9 participants last post by  EOD Guy  
#1 ·
:) Has anyone used the remote battery disconnect whereas the power is killed by a solenoid? Reason I ask is that many of the disconnect switches cause you to drill a large hole through the floor (for mounting). I'm limited for space and need somewhere to mount the switch. Underneath the seat would be nice but there is no room because of the frame, transmission, mufflers, crossmember, etc... the battery is mounted under the floor boards beneath the passenger seat and there is very limited room there, hence the question. Could one make this remote battery disconnect and is it feasible?
 
#3 ·
Yep - I did it and this is the thread (ya gotta use the search function:D):

http://www.hotrodders.com/forum/battery-isolator-212060.html

The drawing was recently updated as there was an error

After over a year, still works very nicely. You do have to use a latching solenoid as a regular momentary Ford style will not work. The Cole-Hersee 24200 is the only one generally available but I am aware of quality problems with them lately, now being made off shore.
 
#4 ·
It is very easy to do, but I'm not a fan of them. I like the old manual switch....... If you don't have room to drill that large hole (I know exactly what you're talking about) My solution in one case was to mount the switch in an unaccessable area inside a alum box, I then drilled a 1/4" hole in the alum box and inserted a 1/4" rod with a split pin installed (it did the same function as the orig key) the rod was about 6" long, and entered the cab just in front of the dvr's seat , it was pretty neat. basicly I made a new key.
 
#5 ·
Here is what I have been using lately. Its a latching or bi-stable impulse solenoid sold through Watsons Streetworks. Trip the solenoid and it turns on and stays on, trip it again and it turns off and stays off. Works with any momentary switch or button rated for 1 amp or more, and it only draws power while the button is pressed.

Much of what I work on are street rods, and one of the neat things about this is it can be made to work by remote control (of course the remote receiver would have to be wired so it gets power upstream of the battery shut-off solenoid). I've put in six or seven of them in the past few years, and haven't had any problems yet.

It's kind of expensive though...$110 + frt + switch
(link)


Here's the rear electrical panel in a '39 Ford street rod I wired recently. The battery disconnect solenoid is in the lower middle.

Image


Hope this helps.....:thumbup:
Joe G.
 
#6 ·
:D Thanks for the replies guys! "Irelands Child", I have your schematic but looking at it I notice a 10 amp fuse. If the fuse blows, for whatever reason, then I assume that everything is dead in the car. This means that if you have power doors then you would have to tap from the positive lead (#1) of the solenoid before the fuse, as the power to the doors draws more than 10 amps. Reasoning: You have to get inside because you have a cable release inside the car for your trunk (where the battery and the solenoid/fuse disconnect is) and you have to replace the fuse, which is also inside the car which also feeds the linear actuators that open the trunk. Going through these motions as I have the battery in the trunk and the trunk has actuators. Been caught more than once with blown fuses or dead battery.
 
#7 ·
I didn't go back and fully reread my original post but I have my electric trunk lift as well as the stereo on a bypass circuit which have their own set of fuses. If you were to do this mod on a computer controlled engine, that too would need to be on the bypass circuit.
 
#9 ·
496

Sure, if you have an aux channel in your current alarm system ie..... trunk release, that output signal can be used to pwr a relay that in turn would pwr the solenoid. If the current from the output is strong enough, it could be used to fire the solenoid directly.
 
#13 ·
I've been going through all of the remote battery disconnect threads posted here, and this one, although 8 months old, appears to be the latest, so I'll reply here.
Has anyone bought a Watsons/Painless solenoid to see if it is actually the Cole Hersee 24200? The reason I'm asking is this: Nowhere have I found the "surge" rating of the C-H solenoid. Yes, they all say that they are good for 110 amps continuous, but how about the surge current to the starter? I've read that starters can pull upwards of 3 or 4 times that amount.
The only mention of surge current capacity is on Watson's website where they state that their solenoid is good for 750 Amps.
Just curious if anyone has looked into this. I like to save a few bucks just like everyone else and get a C-H 24200, if in fact it is equivalent to the Watson's unit and up to the task.
Thanks for any feedback,
Steve
 
#16 ·
Even if the C-H24200 can't take a full starter draw for very long.. why would it need to.. if you use a ford fender mount starter solenoid for the starter, the starter load is off the c-h24200 as it'll only be turning on/off the power supply source for the trigger power to the starter circuit and until that trigger is powered the battery is disconnected from the starter circuit.. yes if you jumped the ford it crank.. but that's it.. and if it's not out in the open like ford installed it.. no one could use it to try to hot wire the car either..
seems like a win win.. takes the huge load of the battery kill switch and gets you all the pluses of the ford starter solenoid.. a lug to power your radio memory/ecu memory and for g.m. owners most of the hot start issues..
I'd think with the c-h24200 never dealing with the 100+ amp starter draw it last a lot longer..

any reason this wouldn't be ideal..
 
#14 ·
Steve, I just looked at one I am in the process of installing and it has C-H molded into the plastic piece and the number '24200' stamped on the other end. So I believe you are correct in your assumption. :thumbup:

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C-H's own datasheet (link) does not specify what the intermittent load rating is on the solenoid. But they've been holding up on the cars I've installed them on.

Hope this helps....:thumbup:
 
#15 ·
Thanks for the response, Joe. So, that solenoid in your picture is the Watson's unit? Looks like that's the way I'll be going.
I sent an e-mail to C-H (Littlefuse) to their engineering department but have not heard back yet.
I've got an early Hemi motor with 8:1 c.r., so the starter won't be having to work too hard in spinning the motor over. The starter is the Mopar lightweight Denso-style gear reduction starter. Doing a little research, I found that the started will pull around 175 amps cranking under "normal" conditions.
With so many of these solenoids sold from Watson's, Painless. etc., and never hearing of any over-current problems with them, I'm sure they're up to the job.
Impressive wiring job on that '39...neat and clean...

Steve
 
#17 ·
Thanks for the response, Joe. So, that solenoid in your picture is the Watson's unit?
That is correct.

...I've got an early Hemi motor with 8:1 c.r., so the starter won't be having to work too hard in spinning the motor over. The starter is the Mopar lightweight Denso-style gear reduction starter.
That sounds like the same setup we did on 'Miss Vicky,' a 354 and a mini starter. It also has a Watson's battery disconnect solenid. She's been a daily driver (Summer in MN and winter in AZ) for two years now, without any troubles.

Image


Impressive wiring job on that '39...neat and clean...
Thank you very much. :thumbup: