Question What does the inverter actually power, and when?

[Neal]

Thanks, folks.

Here's a photo of my electrical cabinet. I think the MADP may be different than the DSDP and VTDP; we have two separate breaker panels side-by-side, as shown.

View attachment 2593

We were incorrect in saying that the microwave does not work off the inverter; it does. I just dropped the park power to confirm that. LadyDi was sure it didn't. We do have the all-electric option in our coach with 3K watt Xantrex inverter and 8 AGM batteries.

Since the breakers in the smaller black panel are labeled for the three slides, "reefer" and microwave, I think that is the inverter side. The larger gray panel at the right is labeled for things like the block heater, washer, dryer, Oasis electric heater elements, inverter, etc. This would be the AC breaker panel.

And, the "pass-through" explanation offered by @Chuggs on how the inverter powers things makes sense. Apparently, the inverter senses the presence of 120VAC and passes it through. When no AC is sensed, it substitutes power produced from the batteries. That's kind of what I was trying to say when I called it a "bypass."

Thanks, folks for helping me sort this all out and get a handle on it. One tiny grain of sand chipped off the granite block that rests on my shoulders.

TJ

Yes, yours is very different being separate. On first thought I figured that's nice, then I realized you have no way to add things to the inverter circuit such as several of us have put the option to drive the front AC off of inverter (solar backed). I guess you would have to replace the panel but moot as I know that's not something you would do, just my analysis of the difference in what I have vs. the MADP.

 

[TJ&LadyDi]

Yes, yours is very different being separate. On first thought I figured that's nice, then I realized you have no way to add things to the inverter circuit such as several of us have put the option to drive the front AC off of inverter (solar backed). I guess you would have to replace the panel but moot as I know that's not something you would do, just my analysis of the difference in what I have vs. the MADP.

Actually, it looks like there is room for one more double breaker if you cut out the front panel. That assumes that the buss bar goes all the way across. Otherwise, changing out the box for one that would take the fifth set of double breakers would not be a big deal; 20 minutes work at most.

TJ

 

[J&JD]

What am I missing here? If TJ was hooked to shore power, and the inverter is passing through that 120v power source, why would the breaker on the inverter pop? Shouldn’t all the load be absorbed by shore power leaving the inverter in a “passive pass through mode”. Probably a simple answer Out there for a befuddled guy??.

 

[TJ&LadyDi]

I have the same question! And, I didn't get an answer from the Newmar tech when I asked. Anyone?

Dr. Chuggs, please report to the forum!

TJ

 

[Just George]

Well I'm not Dr. Chuggs but here's my explanation based on my understanding of typical inverter operation. When an inverter is in "standby" or pass through mode it is passing the input AC voltage through to the inverter AC output. The wiring and components (transfer relay etc.) within the inverter cannot handle an unlimited amount of current so there is at least one circuit breaker in line to protect the inverter. Most if not all will have a circuit breaker on the AC input, some may also have circuit breakers on the AC output. In addition to the circuit breaker protection some inverters have built in overload protection that will shut down the inverter in the event of an overload condition. The inverter can then be restarted once the overload condition is addressed.

 

[TJ&LadyDi]

Well I'm not Dr. Chuggs but here's my explanation based on my understanding of typical inverter operation. When an inverter is in "standby" or pass through mode it is passing the input AC voltage through to the inverter AC output. The wiring and components (transfer relay etc.) within the inverter cannot handle an unlimited amount of current so there is at least one circuit breaker in line to protect the inverter. Most if not all will have a circuit breaker on the AC input, some may also have circuit breakers on the AC output. In addition to the circuit breaker protection some inverters have built in overload protection that will shut down the inverter in the event of an overload condition. The inverter can then be restarted once the overload condition is addressed.

Thanks for that explanation. I suspect that we had an "overload" and tripped the inverter breaker, thus disabling all operation, including pass through. Too many fashion-conscious ladies aboard. "Did I say that?"

TJ

 

[J&JD]

Thanks for that explanation. I suspect that we had an "overload" and tripped the inverter breaker, thus disabling all operation, including pass through. Too many fashion-conscious ladies aboard. "Did I say that?"

TJ

Well I'm not Dr. Chuggs but here's my explanation based on my understanding of typical inverter operation. When an inverter is in "standby" or pass through mode it is passing the input AC voltage through to the inverter AC output. The wiring and components (transfer relay etc.) within the inverter cannot handle an unlimited amount of current so there is at least one circuit breaker in line to protect the inverter. Most if not all will have a circuit breaker on the AC input, some may also have circuit breakers on the AC output. In addition to the circuit breaker protection some inverters have built in overload protection that will shut down the inverter in the event of an overload condition. The inverter can then be restarted once the overload condition is addressed.

Well I'm not Dr. Chuggs but here's my explanation based on my understanding of typical inverter operation. When an inverter is in "standby" or pass through mode it is passing the input AC voltage through to the inverter AC output. The wiring and components (transfer relay etc.) within the inverter cannot handle an unlimited amount of current so there is at least one circuit breaker in line to protect the inverter. Most if not all will have a circuit breaker on the AC input, some may also have circuit breakers on the AC output. In addition to the circuit breaker protection some inverters have built in overload protection that will shut down the inverter in the event of an overload condition. The inverter can then be restarted once the overload condition is addressed.

So you’re saying it was TJ’s curling iron that was to blame?

 

[TJ&LadyDi]

So you’re saying it was TJ’s curling iron that was to blame?

TJ would be happy to find something on his ol' noggin to curl! Now, TJ's daughter and granddaughter are a different story. Rest assured, we will be having a family conference on RV etiquette in the near future.

TJ

 

[Joe Hogan]

Luckily Newmar does a decent job of labeling electrical circuits. Newmar does NOT maintain a wiring diagram for your coach. I have tried and tried to get a diagram to no avail.
However, when at Newmar Service center, ask one of their electrical techs, they can tell you immediately where a factory install wire or circuit is located.
This year at Newmar Service Center I discussed a short in the basement lights (caused by Solar installer it turns out) that we had been chasing for 8 months ( two techs at various times during the year were unable to find the fault,).
The Newmar tech looked at the RV, hooked up fault finder, and knew right where to look. Found and fixed the issues within 45 minutes. That included removing and reinstalling the fireplace.

 

[RandyB]

Clip from Magnum MS Series manual: