Anybody have some experience with the on a cat 730 , that 120 amp fuse of the aternator keep tripping out? Any common issues where to check?
Post a serial number - the wrenches on the board will need one to help diagnose the problem.
serial 3T303196
As long as the engine stays idle every thing is ok. Meter showing 25v or 26 volts. on 27 volts it trips off. I checked for lose wire connection, battery terminals cleaned . nothing showing on the board no code . I am just thinking the breaker itself is getting tired.
@Nige is the one to help with this situation.
Voltage is not what will be tripping the breaker, amperage is. It is rated at 120 amperes nominal, so it should take somewhat more current than that to trip it. My first suggestion would be an amp clamp over the power supply wire as it comes into the breaker and measure what current it is carrying. If the breaker trips at way below the rated 120A then, as you say, it is tired and should be replaced. Part Number is 216-4970.
Thanks Nige, i have no amp clamp, so i got to look for one
Measuring the current in that wire is really the only way of determining at what amperage the breaker is tripping.
Uni-T has a reasonably priced one, or they did before this year. Make sure to read up on the operating manual to run it correctly.
There is of course the possibility that a defective alternator regulator is allowing it to produce too much current. That’s why I suggested measuring what is flowing to the breaker as a first step.
The current reaches 48- 53 amps , I bridged the the 2 terminals of the breaker to check what amps it reaching, 61 amps with the ac on and all lights
Even 61 amps should not cause a 120-amp rated breaker to trip.
That charging voltage seems quite low. 26 volts is barely enough to maintain batteries, assuming it's a 24 volt system.
Yess thats true, i already ordered a new one
Nige can you also help with the 4 number passcode of the display of a cat m318f. i got called in for a service, now a i have to reset the counter .
Try 9992 or FFF2. One or other should work.
Yes but you note that the OP said the breaker always tripped when the system voltage reached 27V rising. So the maximum voltage when the system is charging could well be higher than that, but until the breaker will stay in nobody knows.
If one of the connections on the breaker are loose, that would cause heating that would affect the trip point of the breaker. A visual inspection looking for signs of heating or corrosion followed by a screw tightening wouldn’t hurt.
Hi Nige, i changed a new breaker, and it works ok. It was the breaker it self