20 amp breaker on Cummins Onan 5500 generator trips frequently

[David-and-Cheryl]

We have a Cummins Onan 5500 series generator with one 30 amp and one 20 amp breaker. The 20 amp breaker trips frequently when more than one appliance (e.g., the microwave and the coffee maker, or the coffee maker and the 120v water heater) are on, even when there's nothing else drawing current. And oddly, it doesn't trip when the second appliance starts up, but usually a couple of minutes afterward.

I have a Progressive EMS with a remote display, and it shows far less than 20 amps on either leg of the AC at any given time when this happens - usually 11 to 15 amps.

Does this sound like a faulty 20 amp breaker, or some other problem?

I'm inclined to replace that 20 amp breaker with a 30 amp, as others have pointed out in this forum that the generator is also made in a 30/30 model.

 

[danemayer]

David,

The water heater is definitely controlled by a thermostat and the coffee maker could be. So at any given moment, you could see current draw from 0, 1, or 2 devices, each pulling between 10 and 15 amps. In addition, there are hidden loads. The Power Converter is running all the time and can easily draw 8 amps at certain times. I've also been told that there times where the Power Converter can pull >15 amps momentarily, which is why it's got a 20 amp plug and outlet.

My guess would be that you're simply pulling more than 20 amps on that leg once in a while, tripping the breaker. A 30 amp breaker might alleviate that.

Another approach would be to switch the water heater to propane operation in the morning when the coffee pot is on.

 

[richheck]

Best to follow what Jerrod did, replacing the 20 with a 30.

Project-LM-365 #73

Link to to his project : https://heartlandowners.org/showthread.php/54076-Project-LM-365?p=481847&viewfull=1#post481847

 

[David-and-Cheryl]

David,

The water heater is definitely controlled by a thermostat and the coffee maker could be. So at any given moment, you could see current draw from 0, 1, or 2 devices, each pulling between 10 and 15 amps. In addition, there are hidden loads. The Power Converter is running all the time and can easily draw 8 amps at certain times. I've also been told that there times where the Power Converter can pull >15 amps momentarily, which is why it's got a 20 amp plug and outlet.

My guess would be that you're simply pulling more than 20 amps on that leg once in a while, tripping the breaker. A 30 amp breaker might alleviate that.

Another approach would be to switch the water heater to propane operation in the morning when the coffee pot is on.

Thanks Dan, that's what I'm going to do. (And I did figure out to switch the water heater to propane when making coffee...hard to do that much thinking pre-coffee, however!

- - - Updated - - -

Best to follow what Jerrod did, replacing the 20 with a 30.

Project-LM-365 #73

Link to to his project : https://heartlandowners.org/showthread.php/54076-Project-LM-365?p=481847&viewfull=1#post481847

Thanks, that's helpful. I just ordered the part - should have it next week.

 

[Jesstruckn/Jesstalkn]

Mine came fast and it was easy to replace. Good luck and hope that solves your problems. I really haven't put mine through the test yet. Be sure to let use know the results.