Go Back   iRV2 Forums > iRV2.com COMMUNITY FORUMS > iRV2.com General Discussion
Click Here to Login
Join iRV2 Today

Mission Statement: Supporting thoughtful exchange of knowledge, values and experience among RV enthusiasts.
Reply
  This discussion is proudly sponsored by:
Please support our sponsors and let them know you heard about their products on iRV2
 
Thread Tools Search this Thread Display Modes
 
Old 05-19-2015, 05:44 PM   #15
Moderator Emeritus
 
Gary RVRoamer's Avatar


 
Join Date: Jan 2000
Location: Silver Springs, FL. USA
Posts: 18,073
He needs a diode rated for a minimum of 10 amp for the Toad Charge line.

But I'm pretty sure the Toad Charge already has built in circuitry to prevent reverse current flow. Their FAQ age even describes it. Not clear if the OP is using a Toad Charge or a DIY connection this time. He says he had trouble with TC wiring.
TOAD-CHARGE Frequently-Asked Questions
__________________

__________________
Gary Brinck
Former owner of 2004 American Tradition
Home is in the Ocala Nat'l Forest near Ocala, FL
Summers in Black Mountain, NC
Gary RVRoamer is offline   Reply With Quote
Join the #1 RV Forum Today - It's Totally Free!

iRV2.com RV Community - Are you about to start a new improvement on your RV or need some help with some maintenance? Do you need advice on what products to buy? Or maybe you can give others some advice? No matter where you fit in you'll find that iRV2 is a great community to join. Best of all it's totally FREE!

You are currently viewing our boards as a guest so you have limited access to our community. Please take the time to register and you will gain a lot of great new features including; the ability to participate in discussions, network with other RV owners, see fewer ads, upload photographs, create an RV blog, send private messages and so much, much more!

Old 05-19-2015, 06:19 PM   #16
Senior Member
 
mhbell's Avatar
 
Thor Owners Club
Ford Super Duty Owner
Georgie Boy Owners Club
Join Date: Feb 2011
Location: Ogden Utah
Posts: 522
This is what you would need if you are trying to charge the battery in the toad and keep the starting battery in the motor home Isolated and prevent feed back. It is called a battery Isolator. here is one for $16 on amazon com. Stinger SGP38 80-AMP Battery Isolator and Relay.
Mel
__________________

__________________
2017 Forest River EVO 2360 TT Towed with a 2011 Ford F-250 Super Cab Heavy Duty 4WD Towing Package, Blue OX Sway Pro Hitch.
http://www.rvbloggers.wordpress.com
mhbell is offline   Reply With Quote
Old 05-19-2015, 06:37 PM   #17
Senior Member
 
Pigman1's Avatar
 
Join Date: Sep 2011
Posts: 1,938
I guess you can put all that stuff between the toad and MH if you want to waste your money, but we don't. My 7 pin connectors at the back of the MH have a pole called BAT +12V. Wire from there to the toad battery with a 10ga wire and put a 25A fuse within a few inches of the toad battery. The MH connection is on the IGN switch, so no connection until the key is on and no back feed. It's also fused at the MH end. We've been pulling 3 different toads with three different class A's that way for almost 200,000 miles and never had a problem.
__________________
Pigman
2013 Tiffin Allegro Bus 43QGP
2011 Chevy Silverado 1500 Toad
Pigman1 is offline   Reply With Quote
Old 05-19-2015, 07:04 PM   #18
Senior Member
 
Rich and Cork's Avatar
 
Join Date: Jan 2006
Posts: 1,052
You don't want diodes for what you are wanting to do. You just need fuses to protect from shorting.
__________________
2001 34' Alpine Coach
2008 Jeep Rubicon or 2012 Ford F150 4x4 Lariat towds
or a couple of different trailers
Retired in Apple Valley, California
Rich and Cork is offline   Reply With Quote
Old 05-19-2015, 07:34 PM   #19
Senior Member
 
Join Date: Sep 2012
Posts: 5,948
To do it correctly there should be isolation between the batteries. It's true that most of the time it works without it. The diode is there for when it does not. This looks like a reasonable device:

Battery-Related Products | Battery Isolators48051 | Cole Hersee - Littelfuse

Anything similar will work.

The ~0.3 VDC drop may prevent the battery form being maintained at 100% but it will maintain it at a high level of charge. If the alternator output is high enough it will not matter at all. The normal situation is that there is a low current flow to equal the phantom drains not the high capacity needed if there is a big difference in charge levels.
__________________
nothermark is offline   Reply With Quote
Old 05-20-2015, 05:38 AM   #20
Senior Member
 
maxwell18's Avatar


 
Monaco Owners Club
Join Date: May 2013
Location: Pace FL 32571
Posts: 285
I am the OP, I have tried Toad Charge, if you used it or seen it you could see the connections are mickie mouse. My toad requires to have the key on to tow and draws alot of juice. I already have a CB in line all I wanted was diode in line to protect the expenesive MH circuits, cheap insurance. I know if anying can go wrong, IT WILL. Thanks for all the help and I did learn something.
__________________
Bruce and Carolyn, Sissy the Boss
2005 Monaco Diplomat M-40PAQ
400ISL Cummins
maxwell18 is offline   Reply With Quote
Old 05-20-2015, 07:13 AM   #21
Registered User
 
mel s's Avatar
 
Join Date: Mar 2010
Posts: 8,777
Quote:
Originally Posted by wa8yxm View Post

A diode isolator (Battery isolator) comes with a pair (or 3) diodes.. Two are big mothers, encased in epoxy and aluminum they can pass easily 70-80-90 amps depending on the model
The third (if present) is smaller.

BUT there is a problem... THe voltage drop may prevent proper towed charging.

US-Gear (unified brake decelrator) puts a line from the motor home battery to the towed battery 20 amp breaker at one end 40 at the other (I'd use 20's both ends for your install) the self resetting thermal kind.

Now that works.. Very low voltage drop.. It is how I handle my towed.
wa8yxm
The 2 breakers are a good idea.
However, I believe a single diode should also be used in a charge line... (to prevent toad battery voltage from flowing into the 12V electrical system of the coach).

Mel
'96 Safari
__________________
mel s is offline   Reply With Quote
Old 05-20-2015, 08:51 AM   #22
Senior Member
 
Tiffin Owners Club
Freightliner Owners Club
Join Date: Aug 2014
Posts: 1,845
Quote:
Originally Posted by maxwell18 View Post
I am the OP, I have tried Toad Charge, if you used it or seen it you could see the connections are mickie mouse. My toad requires to have the key on to tow and draws alot of juice. I already have a CB in line all I wanted was diode in line to protect the expenesive MH circuits, cheap insurance. I know if anying can go wrong, IT WILL. Thanks for all the help and I did learn something.
A diode is a one way switch. It does not protect against voltage spikes.
It is not perfect, so depending on the material, it can have up to .75 volt drop.
When your motorhome is putting out 14v charge voltage your toad will be see less.
13.8v is the normal float charge voltage. About 14.5v is a fast charge voltage.

Inside your motorhome, the charge solenoid actually ties your house and chassis batteries together (no diode).

If you have a Freightliner chassis, the 12v line on the trailer connector is ignition controlled and runs through a relay. So the worst that can happen is if the key was left on, engine off, your toad and chassis batteries would be in parallel.

If you want a well functioning charging circuit, don't use a diode.
If your concerned about draining the toad battery, put a relay in the charge line (if not Freightliner).

As far as protection against voltage spikes, the diode will only block negative spikes from the coach.

You are sacrificing having a fully charged toad for a false sense of protection.

Good luck.

Regards,

Dan
__________________
2014 40QBH Phaeton DP Cummins 380HP ISL, Freightliner XC, 2014 Jeep Trailhawk TOAD
Blue Ox Aventa tow bar, SMI Air Force One -South Orange County Ca.
dpinvidic is offline   Reply With Quote
Old 05-20-2015, 09:06 AM   #23
YC1
Senior Member
 
YC1's Avatar


 
Holiday Rambler Owners Club
Join Date: Jun 2011
Posts: 5,563
I'm a Certified Electronic tech with 40 yrs working on 12 volt systems in every imaginable type of vehicle.

IF the MH only charges with the ignition on then don't wast time, money, and the energy lost on using a diode. You are gaining zero protection.

A diode capable of handling a lot of current is big and not cheap. If you must, then consider buying a small battery isolator that can handle heavy currents and has a heat sink.

Here is an example. You can probably buy one at most automotive stores. You could even jumper the two output post.

http://www.boatersland.com/gue2501.h...FUERHwodp5EAOg
__________________
Myron & Deborah
08 HR Endeavor 40 SKQ
2012 Ford Edge Limited FWD 3.5L
Aluminator tow bar, Demco base plate
YC1 is offline   Reply With Quote
Old 05-21-2015, 07:47 AM   #24
Senior Member
 
Join Date: Sep 2012
Posts: 5,948
You are missing the point of the diode. It is only there to keep the towed battery from discharging through the motor home while keeping the towed battery somewhere near full charge when driving. To do that it does not have to put full float charge on the towed battery though it may. The current is significantly lower than the diode rated maximum current when in float mode. Forward bias lower current will be less than the maximum drops being tossed around. The only reason the current capacity on the diode needs to be high is in case the battery on the towed is low compared to the battery on the coach when everything is hooked up. Then the current can be higher but the drop does not matter because of the differential in voltage. If anything it is a better way to charge as it is not slamming the towed battery with a high charge current. The latter is not a good idea as it can damage the battery or shorten it's service life. That is exactly what a relay will do.
__________________
nothermark is offline   Reply With Quote
Old 05-21-2015, 08:49 AM   #25
Senior Member
 
Tiffin Owners Club
Freightliner Owners Club
Join Date: Aug 2014
Posts: 1,845
Then order one of these from Amazon for $21 and call it a day.

Towed Vehicle Battery Maintainer

Dan
__________________
2014 40QBH Phaeton DP Cummins 380HP ISL, Freightliner XC, 2014 Jeep Trailhawk TOAD
Blue Ox Aventa tow bar, SMI Air Force One -South Orange County Ca.
dpinvidic is offline   Reply With Quote
Old 05-21-2015, 09:02 AM   #26
Senior Member
 
Pigman1's Avatar
 
Join Date: Sep 2011
Posts: 1,938
Quote:
Originally Posted by nothermark View Post
You are missing the point of the diode. It is only there to keep the towed battery from discharging through the motor home while keeping the towed battery somewhere near full charge when driving. To do that it does not have to put full float charge on the towed battery though it may. The current is significantly lower than the diode rated maximum current when in float mode. Forward bias lower current will be less than the maximum drops being tossed around. The only reason the current capacity on the diode needs to be high is in case the battery on the towed is low compared to the battery on the coach when everything is hooked up. Then the current can be higher but the drop does not matter because of the differential in voltage. If anything it is a better way to charge as it is not slamming the towed battery with a high charge current. The latter is not a good idea as it can damage the battery or shorten it's service life. That is exactly what a relay will do.
Huh? Just what do you think the voltage regulator on any vehicle does? Damage a battery and shorten it's life? Since you're bound and determined to spend your money on something that's not needed, go right ahead, but don't try to justify it by claiming some of the manufacturers propaganda is The Gospel.
__________________
Pigman
2013 Tiffin Allegro Bus 43QGP
2011 Chevy Silverado 1500 Toad
Pigman1 is offline   Reply With Quote
Old 05-21-2015, 09:02 AM   #27
Senior Member
 
Join Date: Feb 2010
Posts: 4,492
Many options are provided but before doing anything just get a voltmeter and check the interface to see if you need to do anything at all.

If it is constant hot maybe but if only hot with key on you are set to go.
__________________
Tony & Lori
1989 Country Coach Savannah SE
TQ60 is offline   Reply With Quote
Old 05-23-2015, 11:47 AM   #28
Senior Member
Commercial Member
 
Join Date: Jun 2005
Location: behind the steering wheel
Posts: 992
frys electronics has what you need.
__________________

__________________
azpete is offline   Reply With Quote
Reply



Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
2007 Camelot- I cant find Gravity Fill or Drain JRPA Monaco Owner's Forum 13 07-23-2014 05:17 PM
Where to find RV inspectors Shamrockken iRV2.com General Discussion 11 07-08-2014 08:49 PM
Trying to find walkie talkie replacements Touring Tom Class A Motorhome Discussions 5 07-02-2014 07:53 AM
2005 Kountry Star - where to find the fuse for the LP detector bensharr Newmar Owner's Forum 5 03-22-2014 03:36 PM
Alpine 2004: Dash Warning Buzzer quit working, can't find it! Mike & Mike Alpine Coach Owner's Forum 6 06-23-2013 11:00 PM

» Virginia Campgrounds

Reviews provided by


Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -6. The time now is 03:30 AM.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.