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positive ground

smoke

Member
Joined
Oct 21, 2017
Messages
10
Location
greenville, ga
series......does any one know if my samsung excavator is positive ground?....cant i remove wires from solenoid ..small wires i assume are what powers fuse console/key start...and run a dedicated wire to the b terminal on starter switch and that will power the fuse panel....i found the starter relay that looks like mushroom, both large wire terminal post zero voltage...does this tractor have some type of anti-theft system causing this as well
 

Ronsii

Senior Member
Joined
Jun 26, 2011
Messages
3,464
Location
Western Washington
Occupation
s/e Heavy equipment operator
Would be very helpful if you could give us all the information you have regarding your excavator(year,model,type,serial number,etc...) and also what you are trying to accomplish or the issues it has and it's history, many of these machines are very similar in how they are wired and the problems they might have. The problem you mention about zero voltage on the large posts of the relay could be many things... including a blown fusible link in the wiring to not testing them properly... even pictures can shed a lot of light on the issues at hand if you don't know the specs of your machine.
 

Delmer

Senior Member
Joined
Jan 3, 2013
Messages
8,891
Location
WI
I really doubt a Samsung is positive ground, but...
Check on the alternator label if you can see it, it will clearly say 12 or 24V negative/positive ground on nearly every alternator I've ever seen.
 

007

Senior Member
Joined
Dec 28, 2016
Messages
282
Location
Australia
The starter operation is not affected by polarity normally unless very exotic.
Negative ground has become almost universal these days on vehicles and machinery except for marine.
Its your alternator and electronics which are polarity specific.
You can use a multi meter or bulb on your alternator to confirm its polarity if you become totally confused.
 

Mobiltech

Senior Member
Joined
Jan 14, 2014
Messages
1,697
Location
Sask.
Occupation
Self employed Heavy duty mechanic
I have seen some excavators that are negative ground will have a positive disconnect relay between the battery positive cable and the starter. In these machines there is one small positive wire that goes only to the key which then powers the positive disconnect to turn on when the key is in the run position.
 

smoke

Member
Joined
Oct 21, 2017
Messages
10
Location
greenville, ga
my tractor is a samsung SE 280 LC, someone tried to steal it. cut wire in fuse panel and tried to hot wire to start due to not having a key...they spliced wires with different colors. they ran two wires from the starter solenoid to the fuse console, but were not connected, they did look however as if they had been touched to something because of the shorted look.when i connect the battery cables to batteries within 10 min both will be down to 2.3 volts...i disconnected the small hot wire from the starter and the batteries will stay charged...thats why i need a wiring diagram that will show the path from the starter to start/key switch...i also cannot get voltage to the b side of starter key switch..
 

007

Senior Member
Joined
Dec 28, 2016
Messages
282
Location
Australia
You sound like you have a few things to sort out there.
Sounds like one or both of your battery's are dead flat or died and will need a battery charger on them before you get this started.
No Power to the b position on the key could be blown fuseable link.
Chances are they have probably not damaged much apart from the mangled wires at the key.
Worst is discharging your batterys that low would have shortened there life big time if not killed them.
An auto electrician would be able to tidy up those wires for you real quick if you had one handy.
You can burn wires pretty quick with 24v so do a good job of splicing new wires on your key switch.
 

smoke

Member
Joined
Oct 21, 2017
Messages
10
Location
greenville, ga
thanks 007, i have no problem wiring, i dont have a wiring diagram, therefor im taking baby steps because of the 24 vdc. the folks that did this obviously spent a while trying to wire it...all the way to starter and starter solenoid was cut spliced with green wire....most of the wires in the harnesses , the key switch, the fuse panel were cut and the loose wires in the harness was pulled about 2 feet from where they were cut, and had spliced the green wire there as well...when i connect the small hot wire on the starter battiers drain in 10 min to 2.3 volts...i could have only the neg connected at the batteries and pos side cable removed i can put my meter on it to grd and have voltage put back on then 0 volts
 
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