What now....I hate electrical problems !!!!

[Dick1142]

I hate it when things (especially electrical) all of a sudden start working differently.

CONDITIONS: My 50 amp system is plugged into a 30 amp power source in my garage. Problem described below is the same if my generator is the power source. Problem is also the same whether or not the Xantrex 458 charger/inverter is on or off.

PREVIOUS (and desired) SITUATION: Whenever operating appliances I could watch my load meter, and when I got to 30 amps the system would start to automatically "load shed", and I had no problems staying within the 30 amp limit.

CURRENT SITUATION: All of a sudden (?) I am tripping the "leg 2" 20 amp breaker on the Xantrex as soon as I get to 20 amps...the "load shed" feature never comes into play. This severly limits my ability to operate heaters, water heater, or anything else simultaneously.

PROBLEM AND SOLUTION: Wish I knew. Any ideas from anyone would be appreciated.

Dick

[Rex]

Disconnect from shore power and leave the generator turned off. Turn off the battery disconnect switches, and the Inverter. Now open the inverter wiring panel and make sure all the terminals are tight.

Next make sure all GFI's are reset. Don't forget the one in your basement if you have one there.

If that does not do it, you may have a bad Inverter. When on generator or shore power, it's internal transfer switch closes both Legs of the 50-amp circuit through the inverter to the coach even if the inverter is turned off. Sounds like only one Leg of the circuit is being transferred. Same would br true for 30-amps through an adaptor to your 50-amp coach input cable.

[bullydogs1]

Suspect inverter board on its way out..but I would try a reset to the intellitec board (think you unplug power cable to it and then back in to do that)...

[DP01]

Dick:
Just a thought that may or may not help. Is your home 30A supply 120/240V (2 live conductors and 1 neutral)? This is the correct configuration for a 50A RV connection. That will cause your load shedding feature to be inoperative. The Intellitech display will show your supply source, 50A – 30A or Genset. If it reads 50A you have a 120/240 supply, but, only at 30A which may not support your connected loads.
The standard 30A RV connection is 120V (the 2 live conductors are interconnected plus 1 neutral).
Dennis

[Robi.1014]

"I am tripping the "leg 2" 20 amp breaker on the Xantrex as soon as I get to 20 amps...the "load shed" feature never comes into play."

Dick:
Good and bad news here. Good news: everything is working as it should. Bad news: RV-owner is overloading the AC current draw that is available from/through the Xantrex.

If your inverter and its AC-outputs are wired similar to mine, one 20A Xantrex breaker powers the microwave and the other Xantrex 20A breaker powers MOST of the AC receptacles throughout the RV. So when demand currents (TVs, plug-in heaters, significant-other's hair-curling iron, computers, refer's ice-maker, etc.) add up to almost 20 amps, you will trip the 20-A breaker ON the Xantrex. Your power-shed logic-box cannot help you here because it is monitoring (and adding / shedding) devices "up stream" of the Xantrex and its two, 20A breakers.

The power-shed device first kills power to things like roof A/C units, on-board washer/dryer, and the 115VAC function of the hot water heater. My guess is that the shedder never "sheds" power to (and thus through) the Xantrex.

[ShapeShifter]

Quote:

Originally Posted by Dick1142 CURRENT SITUATION: All of a sudden (?) I am tripping the "leg 2" 20 amp breaker on the Xantrex as soon as I get to 20 amps...the "load shed" feature never comes into play. This severly limits my ability to operate heaters, water heater, or anything else simultaneously.

I'm going to guess that everything is working as it is designed.



When you talk about "load shed" I assume you're talking about an Intellitec EMS that's integrated with the breaker panel? if so, there are only a limited number of circuits that it will shed. On my rig, they are (in order)

1. Water Heater
2. Rear Air Conditioner
3. Washer/Dryer
4. Front Air Conditioner

When the total load in the rig is above the 20 or 30 amp threshold (no loads are shed at 50 amp or on generator power) then it will first turn off the water heater, then the rear air conditioner, etc. until the load is below the threshold.

On the other hand, you mention that it's the 20 amp breaker on the output of the Xantrex that is tripping. The Intellitec box knows nothing about this breaker, and will not shed loads to try to keep the load under 20 amps. It's not designed to do this.

I'm going to go out on a limb and guess that you have two or more electric heaters plugged into the outlets in your rig, and all of those outlets are on the same 20 amp output breaker of your Xantrex inverter. That simply won't work, as they will draw too much power.

You need to find outlets that are on a different breaker, and split up the heaters. Plug one heater into one circuit controlled by one breaker, and plug the other heater into a circuit controlled by another breaker.

In my rig, the microwave is plugged into a a circuit fed by a 15 amp breaker on the inverter. All of the other outlets in the rig, except for a few in the back bedroom, are fed from a 20 amp breaking on the inverter. When I want to run two electric heaters, I plug one into a regular outlet in front (which is fed from the 20 amp breaker.) Then I need to plug the other into the microwave outlet or one of the outlets in the bedroom that's on a different circuit. If I plug them both into regular outlets in front, I'll trip the breaker every time.

Does this sound like your situation?



Edit: Looks like Robi.1014 and I were typing at the same time, and are saying exactly the same thing!

[nodine]

Quote:

Originally Posted by Dick1142 I hate it when things (especially electrical) all of a sudden start working differently. CONDITIONS: My 50 amp system is plugged into a 30 amp power source in my garage. Problem described below is the same if my generator is the power source. Problem is also the same whether or not the Xantrex 458 charger/inverter is on or off. PREVIOUS (and desired) SITUATION: Whenever operating appliances I could watch my load meter, and when I got to 30 amps the system would start to automatically "load shed", and I had no problems staying within the 30 amp limit. CURRENT SITUATION: All of a sudden (?) I am tripping the "leg 2" 20 amp breaker on the Xantrex as soon as I get to 20 amps...the "load shed" feature never comes into play. This severly limits my ability to operate heaters, water heater, or anything else simultaneously. PROBLEM AND SOLUTION: Wish I knew. Any ideas from anyone would be appreciated. Dick

Try reseting the Intellitec EMS by removing the panel that covers the 110VAC circuit breakers. Locate the DC power fuse for the EMS and remove it for a short time and then plug it back in. Then check again if the EMS sheds loads as it should. I have had trouble with the EMS and had to reset it in this manner.

Bob

[Radarman]

Wow--Great explanations by Robi and Shapeshifter. My coach works exactly as described by them, and it makes sense. I found out the hard way about the inverter breakers when the DW got out her hair dryer---look out.

[Dick1142]

I will try what Robi and Shapeshifter said, BUT, as I said, it didn't work like this two weeks ago. Under no circumstances can I get the "load shed" or EMS or whatever to operate as before. It seems to me that the entire electrical load is going thru the Xantrex, even when I am plugged in. That leads me to think the power transfer switch may not be operating, and is not diverting the incoming power to the EMS vs the inverter. Does that make sense?? Does anyone know where the auto transfer switch is located? Thanks for all the info, but the perplexing thing is that it didn't operate this way two weeks ago under identical circumstances and loads. Dick

[Robi.1014]

"Under no circumstances can I get the "load shed" or EMS or whatever to operate as before. It seems to me that the entire electrical load is going thru the Xantrex, even when I am plugged in. That leads me to think the power transfer switch may not be operating, and is not diverting the incoming power to the EMS vs the inverter."
Dick, the ATS (switching to shore power or to genset power sources) sends all its "juice" to a circuit-breaker panel ... probably located in your bedroom. It is also in this vicinity that the EMS "sheds" circuits (HWH, A/C, Washer/Dryer) if overloading of the source (30A or 20A shore power, for example) is about to occur. What I'm saying is that your thought that all circuits are somehow being routed through the Xantrex is just not possible...unless some previous owner re-wired stuff. Bob (above) mentions a way to re-boot the EMS. Just for your satisfaction, you might try that after the tests I propose (below).

"Does anyone know where the auto transfer switch is located?"
It's most commonly in the same bay as the main power cord (50A). The test of the ATS is pretty straight forward: if shore power or genset power is being delivered into the RV, then the ATS is doing it's job.

Test of your EMS:
Hook up to 20 or 30A shore power and minimize the amount of load being serviced in your RV (turn-off TVs, HWH, A/C units). The amperage you read on the EMS should be that of what the Xantrex is using to charge the house batteries. Once this value falls to, say, under 5A, now turn on the 120VAC feed to the HWH (which uses around 10A). Are you reading 15A now? BTW, the additional 10A that the EMS is now showing is not going through the Xantrex because the HWH is directly wired to that circuit-breaker panel I mentioned above.

Now to test if the EMS shedding is working:
Plug in a space heater somewhere in the front of the RV (uses about 12A). I say "front of the RV" because that's the best chance that the space heater will be drawing its power through the Xantrex. The 15A reading that was on the EMS (above) will jump up IF you are on a 30A shorepower circuit, but should not jump up if on a 20A circuit (recall: you have a button on the EMS where you tell the EMS that the max value is 20 or 30A). In a 20A-shore-power example, the EMS will shed (turn off) the HWH during this test. If all this happens, the EMS is doing its job.

Sometimes, there are AC-outlets in the RV that are not fed by the Xantrex. If you know of such an outlet, perform your shedding test (per above) by placing the space-heater into this outlet. The EMS indication of power-draw and subsequent shedding should work in this test just like in the test above.

Let us know what you find.

[McDuff]

Just a thought; when things worked before, did you possibly have the space heater(s) set on low power setting? If they were now on high, this would trip the breaker.

[Dick1142]

Quote:

Originally Posted by McDuff Just a thought; when things worked before, did you possibly have the space heater(s) set on low power setting? If they were now on high, this would trip the breaker.

no, it is on low. I will try some of the tested noted above today. dick

[Dick1142]

All is well that ends well....except for my red face. I did the tests suggested by Robi and everything is working fine. I guess my biggest problem (among many) was not realizing that the EMS shows total load, and not necessairly circuit load. Like my wife says, sometimes I get too focused on one thing.

Some things I learned in the process include: the xantrex circuit 1 (20 amp) powers only the microwave; Circuit 2 powers all of the other outlets; the W/D, charger, and HWH are not powered thru the xantrex (and I suspect the A/C units...I didn't check them).

I greatly appreciate the interest and help of everyone, and hope you have a great Christmas (or whatever) and New Year.

Thanks again. Dick

[Robi.1014]

Good query by McDuff asking if the space heater was on low or high. FWIW, I've successfully run a 1500W space heater on high setting (thus it's drawing about 13 amps) while watching the front TV (which implies that the DirecTV receiver was also ON), and the wife was using her laptop. In my case, the 20A breaker on my inverter "hung in there". All this was done while attached to shore-power ... which is to say that I wouldn't punish my house batteries with this kind of load.

And as he rode out of sight, merry Christmas to all, and to all, a good night.