halberstadt

Hello "Country Gentleman". I also have a 2003 Safari Cheetah, and do all my own maintenance. As an aside, you don't really have a Cummins engine - it's a Caterpillar. That's not pertinent to the problem, though. Tim had good advice for you. To clear up the "exciter wire" thing, that wire is actually not an exciter wire, but rather a remote voltage sense wire. The alternator will adjust its output voltage such that the voltage wherever that wire is connected will be 14.7 volts. It is supposed to be connected to the positive connection of the chassis batteries (or a point that is itself connected to that). Monaco/Safari ran that wire to the isolator and connected it to the post of the isolator that goes to the chassis batteries. That wire, and the one that feeds the "ALT FAIL" light relay, are often subject to corroding and breaking where they connect to the alternator, either of which would give an "ALT FAIL" light. In your case, the remote sense wire could have broken anywhere, maybe at the isolator. As long as you now have a good connection from the alternator remote sense post to the chassis batteries or isolator, that problem should be fixed. As Tim suggests, the best next step is to identify if there is a current drain from the chassis batteries, and if so, where it is. I use a multimeter that can clamp around a wire to read the current flowing through it. The most common version of this "clamp-on" ammeter reads only AC current, but there are (more expensive) models that also read DC. If you can find someone with one of these, you can identify which wire leading from tube battery is carrying the unwanted current, which should narrow the possible culprits. Someone mentioned the inverter, but your inverter does not connect to your chassis batteries. I would check the isolator. With the engine running and batteries not significantly discharged, you should measure one voltage (around 15.5 volts) at the center connection (the larger one that comes from the alternator, not a smaller voltage sense wire), and about 0.7 volts less at each of the other two connections (chassis and house battery connections). With the engine off, the alternator connection should read zero and the other two should be around 12 volts or so. Bill Halberstadt

In the discussion of 50 A and 30 A extension cables, it should be noted that there is one combination that actually presents a fire hazard and not just a reduced voltage problem. If you have a 50 A coach and a 30 A extension, the pedestal has a 50 A outlet, and you can't reach the pedestal with just your 50 A cable; you might be tempted to use this combination: Your 50 A cable, then a 50 A to 30 A adapter, then your 30 A cable, then a 30 A to 50 A adapter so that you can plug into the pedestal's 50 A outlet. Bad idea! Starting from the pedestal: the 50 A male to 30 A female adapter will connect one of the two 50 A pedestal circuits to the single hot lead of the 30 A cable. The next 30 A male to 50 A female adapter will connect the 30 A cable's single hot lead to both hot leads of the 50 A cable, and thus to the two 50 A circuits in your RV. At your RV, you could attempt to use a total load of up to 100 A (the two 50 A circuits). For any load higher than 50 A, the pedestal's breaker should trip, but anywhere in the load range between 30 A and 50 A, nothing will prevent overloading of the 30 A cable. In this situation make sure you do not use a 50 A male to 30 A female adapter at the pedestal end, and just use the pedestal's 30 A outlet (if available). Or you may just have to get closer to the pedestal. Bill Halberstadt Newark, DE 2003 Safari Cheetah