Power draw

[TheLooks]

I bought a 4500W generator after checking into starting currents and run currents. My TT has a single AC unit and it ran without a hitch the first time I used it. The second time, just to try out my generator, it ran at first then continually "kicked" out. Until finally catching and running. Last weekend I went to a brand new campground with all new services and since I have a new Power watchdog with an app, I turned on the AC, the refrigerator, and the hot water heater, all electric. After 10 minutes, it blew the breaker on the pole. I restarted it without the hot water heater on, switching to propane, and it blew again. I turned the Ref to propane and tried again. This time it stayed going. At this point I had not remembered the app, so I got it running and tested each device. The AC was 14.8 Amps, the Ref was 2.8 Amps and the Water Heater was 10 Amps. I do not know why the breaker blew with just the 14.8 and 2.8 running.....I could understand it...maybe with all three at 27.6 Amps. What do you guys think?

 

[B52Bombardier1]

You either have an excessively long power cord between the generator and your vehicle or its wire is too small of a thickness (or a little of both) - both cause a voltage drop at your appliances.

Power in watts = volts x amps. Power consumed stays the same and with the voltage drop, the amps required goes up to make this equation balance out on both sides of the "=" sign. Too high of an amps draw pops a circuit breaker.

Is that 4500 watts a constant value or a surge wattage number?

Also please understand that a large inductive motor such as an AC compressor can briefly, for the first few seconds, require as much as 2.5 times its running wattage just to get the spinning mass of the motor up to speed.

Rick

 

[Rich W.]

This sounds like two different questions:

1. What is your “4500w” generator actually capable of (make and model would help).

2. What is the actual draw when your AC cycles on while your electric water heater and fridge are on.

Chances are you would be under 30 amps when your AC, water heater, and fridge are all running, but as B52 pointed out, not when your AC cycles off then tries to start while the water heater and fridge are still drawing their loads.

 

[TheLooks]

Thank you for the responses. I understand the starting current and got a generator to run the AC, but it is 2 questions. My bad. When the generator was not starting the AC, it was just the AC being used. It is a Westinghouse igen 4500/3700. It should have enough power. But it does idle down and may not ramp up quick enough.
When on pole power, I expected to be able to run everything. I do not think the Ref drawing just 2.8 Amps should kick out the breaker when the AC comes on. The wire is factory and the blades fit tight in the receptacle. How would you suggest testing the wire? It does not make sense that the TT has a 30 Amp input plug and won't run everything on a 30 Amp breaker. Or is this normal?

 

[Rich W.]

no it really doesn't make sense, isn’t normal, and I’d suspect the breaker but you said its new and the genny should have plenty of power. I’d also suspect an 11 year old AC unit, but you’ve verified that its only pulling 14 amps. Did you try running the ac plugged in to shore power without the power watchdog?

 

[TheLooks]

I do understand, thank you. I have been involved in construction all my life. Seen lots of stupid things. I don't however remember hearing about people complaining that they could not run their stuff on shore power. But I do understand why. Thank you for spelling it out concisely. Sometimes you just need to bounce things off someone else with a lifetime of work in that area. Seems if the 30 Amp was not sufficient, more campers would come with 50 if that is what they require.

 

[TheLooks]

no it really doesn't make sense, isn’t normal, and I’d suspect the breaker but you said its new and the genny should have plenty of power. I’d also suspect an 11 year old AC unit, but you’ve verified that its only pulling 14 amps. Did you try running the ac plugged in to shore power without the power watchdog?

No I did not try it without the Watchdog......worked fine last fall without it. Good catch!

 

[TheLooks]

If I bought a brand new TT and it would not operate on the service that was built into it, I would be pissed. And 98.5% of the public does not know a watt from an amp to a volt etc. I have the owners manual and all papers....guess I'll look and see what they have to say. But no salesman is going to tell you that you can't run the microwave if the hot water is on or dont start the fridge if the AC is on, etc. I had a house like that once, but it was the power company that was at fault. I had to complain a LOT....and then they apologized after killing my new fridge and stereo and tv........but didn't compensate for them.

 

[Rich W.]

Just like they are conspicuously quiet when it comes to diesel emissions systems. If they told the truth (if they even know it) they’d lose buainess.

 

[TheLooks]

Bob, I have tried to be diplomatic about your curt replies. I find you a bit arrogant...and you proved it with your last post.
First of all, I have extensive experience in a variety of fields from residential to light commercial construction and have rubbed shoulders with many educated and experienced professionals that found my 'common sense" somewhat remarkable. I did not ask for your beatdown. Maybe this is why you got put in timeout in that other forum?

In the last quote of my post, you fail to realize I was talking about the general public, from a general public perception. I know the difference for the 2nd time I have told you. Your comment about the tach and speedometer is way off base. Plus, calling everyone pitiful that YOU think don't have your genius and intellect is well, pitiful.

You like to help but have poor bedside manners. You remind me of the Architect on a large project that got mad when I pointed out that his pretty picture did not work in the real world. Geometry and all got in the way. Come down from your seat on high for a bit.