magnum ME 2012

[terryflt]

Hi
Can any of you good people tell me the difference between the
ME 2012 and the ME 2012-20B.
My unit is fried and I want to replace it but do not want to buy the wrong one.

Thanks
Terry

[2oldman]

GordonThree wrote:
The shore power cable..snip..is protected by the breaker inside shore power subpanel (panel), where the plug is. That breaker is only to protect the shore power cable, not any of the circuits inside the RV.

Ok, that makes sense.

But I'm not sure I understand "where the plug is." It sounds like you have a separate 'subpanel' for that breaker -or you would have said 'the main panel,' where the 30a main breaker is.

Question: When inverting, one 'must' size a breaker to protect the wire coming from the inverter's 120v output? By my calcs, that would be a maximum of a 16a breaker. (2000w/125v), which isn't much of a wire. What about surge.. which can be double that, or 32a?

(No wonder I installed whole house. I just don't overload the inverter.)

[GordonThree]

2oldman wrote:
Then this implies that the circuits in your RV are unsafe to begin with, because a 30a shore hookup is very capable of delivering 2000w.

Maybe I'm a little slow today... this doesn't yet make sense.

The shore power cable doesn't go directly to the microwave / air conditioner, it goes through a subpanel full of circuit breakers first, inside your RV.

The shore power cable is designed to carry its maximum load of 30 (or 50) amps, and is protected by the breaker inside shore power subpanel, where the plug is. That breaker is only to protect the shore power cable, not any of the circuits inside the RV.

[pianotuna]

Hi,

So, plug the shore power cord into the 2012 when you want power. No sub panel required.

[2oldman]

Yep, that's what it says.

[OnaQuest]

2oldman wrote:
Then this implies that the circuits in your RV are unsafe to begin with, because a 30a shore hookup is very capable of delivering 2000w.

Maybe I'm a little slow today... this doesn't yet make sense.

Simply put, the 2012 is designed with a single output, designed to feed a subpanel. The subpanel should have a main breaker with branch circuit breakers.

The 2012 20B is designed with two 15/20 amp outputs that already have branch circuit breakers installed in the Inverter to directly feed outlets or appliances.

[diveman52]

2oldman wrote:
Then this implies that the circuits in your RV are unsafe to begin with, because a 30a shore hookup is very capable of delivering 2000w.

Maybe I'm a little slow today... this doesn't yet make sense.

That's what the circuit breakers are for in the panel.
As for a 2000 watt inverter overloading a 15 amp circuit.I seriously dought that 1.6 amp over will hurt. I have seen lots of overloaded circuit in my time in the trade. It's amazing what 14, 12 or 10 gauge wire will really handle. There's a pretty good margin of safety built into the amp rating of wire.
If you look at the NEC tables it actually says #14 is good for 20 amp but to never put it on anything larger than a 15 amp circuit breaker.

[2oldman]

Then this implies that the circuits in your RV are unsafe to begin with, because a 30a shore hookup is very capable of delivering 2000w.

Maybe I'm a little slow today... this doesn't yet make sense.

[jhilley]

2oldman wrote:

GordonThree wrote:
With 2000 watt output, the inverter could overload a circuit wired with 14 gauge wire (15 amp max), without overloading itself, creating a fire danger.

I understand, but what does that have to do with a subpanel? Does that mean you're supposed to inspect your circuits, and if they're 14awg, put 15a breakers in the subpanel?

Yes that is correct, however there is a little more to it than that.

[2oldman]

GordonThree wrote:
With 2000 watt output, the inverter could overload a circuit wired with 14 gauge wire (15 amp max), without overloading itself, creating a fire danger.

I understand, but what does that have to do with a subpanel? Does that mean you're supposed to inspect your circuits, and if they're 14awg, put 15a breakers in the subpanel?

[GordonThree]

The breakers are to protect the wiring, not the inverter.

With 2000 watt output, the inverter could overload a circuit wired with 14 gauge wire (15 amp max), without overloading itself, creating a fire danger.

[2oldman]

GordonThree wrote:
Without those on board breakers, a subpanel would be required to provide the over-current protection.

What's wrong with the breakers in a main panel? Any decent inverter will cut out if it can't handle the load.

[wolfe10]

2oldman wrote:
In unyalli's post it says 'without requiring an inverter subpanel.' What's that about?

With the two circuit breakers built into that inverter, they serve as the "sub-panel". So hots and neutrals for those circuits would be connected to the inverter output.

[GordonThree]

2oldman wrote:
In unyalli's post it says 'without requiring an inverter subpanel.' What's that about?

Since there are two 15/20 amp circuit breakers on board the inverter, you can wire it directly to outlets, or an appliance. Without those on board breakers, a subpanel would be required to provide the over-current protection.

[2oldman]

In unyalli's post it says 'without requiring an inverter subpanel.' What's that about?