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Topic: Possible "Chassis Ground" Connections (Read 346 times) previous topic - next topic

Possible "Chassis Ground" Connections

Before I get to cutting, crimping and shrink wrapping a ground wire for my solar charge controller, I need to clear up my understanding (or misunderstanding) of what a "chassis ground" is.
I have heard that anything connected to a negative bus bar which shares a connection to the negative post of the starting battery (and starter) eventually grounds to the chassis and is suitable for a chassis ground.
If this is not correct, is the center post in this picture (my #2 choice) a suitable chassis ground?
If neither of those choices are suitable, what would someone familiar with a Foretravel U225 recommend?
 


1993 U225 Build #: 4285
500 Watts Solar
Honda CRV AWD
Former 1981 Foretravel Travco
Retired, Full Time Off Grid Snowbird

Re: Possible "Chassis Ground" Connections

Reply #1 –
That can thing is a solenoid, relay. The center connection is to provide the trigger power to energize the coil to activate the relay. The can grounds the coil. Many coils of this style will have 2 posts for the coil, power and ground. These are often used for circuits that may requires controls on both sides or are switched on the ground side.

As you are learning things electrical, grounds are important for many reasons, but for DC circuits, the ground, or negative is really the source. In a battery where the chemical reaction takes place electrons flow form the positive to negative plates. As the battery is part of the big picture series circuit, outside, the electrons are flowing from the negative terminal back to the positive terminal. 
Dennis Haynes
Bohemia NY
2008 Nimbus 342 SE Carlyle
Build #6475
Motorcade #19148

Re: Possible "Chassis Ground" Connections

Reply #2 –
That's great Dennis. Thank you. I see the amps going through the red wire and back in the black wires with my amp meter. Meanwhile, since my solar power has been disrupted, I have learned that my house battery is not being charged by the converter even though I am connected to shore power. 
1993 U225 Build #: 4285
500 Watts Solar
Honda CRV AWD
Former 1981 Foretravel Travco
Retired, Full Time Off Grid Snowbird

Re: Possible "Chassis Ground" Connections

Reply #3 –
Foretravel has the chassis and the house all grounded together.  Most time there will be posts with a number of green wires connected to it. 

In your picture it is hard to tell,  but it looks like there is a stud in the bottom left of picture that has a number of wires connected to it . It is possible that is a ground. You can verify by taking a test light or volt meter and go to that terminal and one side or the other of the solenoid that is in your picture.  I am not sure what the solenoid is used for but there should be a hot all the  time on at least one side of it.
2014 ih45  (4th Foretravel owned)
 1997 36' U295 Sold in 2020, owned for 19 years
  U240 36' Sold to insurance company after melting in garage fire
    33' Foretravel on Dodge Chassis  Sold very long time ago

Re: Possible "Chassis Ground" Connections

Reply #4 –
I found this explanation ...

Chassis and frame describe the same thing. We use the word chassis to distinguish it from the house. The factory buys a bare chassis with a motor in it the build a MH. Battery negative goes to the chassis/frame. Doesn't matter how many wires you use.
__________________
2011 Keystone Sprinter 323 BHS. Port Charlotte Fl/Hinsdale MA. Retired Master Electrician. All Motor homes are RV's. All RV's are not Motor homes.
1993 U225 Build #: 4285
500 Watts Solar
Honda CRV AWD
Former 1981 Foretravel Travco
Retired, Full Time Off Grid Snowbird

Re: Possible "Chassis Ground" Connections

Reply #5 –
Quote from: turbojack –
Foretravel has the chassis and the house all grounded together.  Most time there will be posts with a number of green wires connected to it. 

In your picture it is hard to tell,  but it looks like there is a stud in the bottom left of picture that has a number of wires connected to it . It is possible that is a ground. You can verify by taking a test light or volt meter and go to that terminal and one side or the other of the solenoid that is in your picture.  I am not sure what the solenoid is used for but there should be a hot all the  time on at least one side of it.
Thanks Jack. That stud is a ground. The voltage on one side of the solenoid shows the same as the house battery and the voltage on the other side is the start battery.
1993 U225 Build #: 4285
500 Watts Solar
Honda CRV AWD
Former 1981 Foretravel Travco
Retired, Full Time Off Grid Snowbird

Re: Possible "Chassis Ground" Connections

Reply #6 –
Quote from: Dakota Slim –
Thanks Jack. That stud is a ground. The voltage on one side of the solenoid shows the same as the house battery and the voltage on the other side is the start battery.


Then that solenoid is your boost solenoid.
2014 ih45  (4th Foretravel owned)
 1997 36' U295 Sold in 2020, owned for 19 years
  U240 36' Sold to insurance company after melting in garage fire
    33' Foretravel on Dodge Chassis  Sold very long time ago

Re: Possible "Chassis Ground" Connections

Reply #7 –
By the way, probably not a good place to place a claw hammer! Jim.
Jim and Dona
2002 U295 36'
Lily, blue healer. Our fury person
Manx mid travel Ecotec turbo
2022 Bronco badlands Sasquatch
Trail 90 and 110cc

Re: Possible "Chassis Ground" Connections

Reply #8 –
Quote from: fourdayoff –
By the way, probably not a good place to place a claw hammer! Jim.
Good eye! I have a lot of tools that I'm moving around for this project. If OSHA came by they'd have a fit.
1993 U225 Build #: 4285
500 Watts Solar
Honda CRV AWD
Former 1981 Foretravel Travco
Retired, Full Time Off Grid Snowbird
 

Re: Possible "Chassis Ground" Connections

Reply #9 –
Yea, OSHA is a pain but burning my coach to the ground would be a bad day. Jim.
Jim and Dona
2002 U295 36'
Lily, blue healer. Our fury person
Manx mid travel Ecotec turbo
2022 Bronco badlands Sasquatch
Trail 90 and 110cc