Electrical mysteries

[Crose55]

This weekend was our maiden trip of our class a motor home. We want to go full time in a year. We headed for a state park for our first trip (close to home!). We have a 2011 Coachmen Sportscoach. it was used only 7 times with 7k miles. We plugged into a 50 amp shore lone at the site. For a while all was fine. Over the day, we kept losing power. The air conditioning worked. All GFI outlets worked fine, but no others. The microwave had no power at all. The inventor w
Irked on and off but reported a fault. The overheads lights dimmed to almost out. Then the air worked on and off. We started the generator and nothing helped. There were no tripped breakers. Then we thought we would go home and figure it out later. However the slides and awnings had no power. Roadside service couldn't find anyone to come and help. We went to bed. This morning the air worked. GFI outlets still worked but no others. Refrigerator would not switch to LP so all was wasted there. But, we pulled in all slides although they came in very slowly. Awning retracted too. Home now but we have no idea where to start. When we purchased the rig, our inspector said everything worked great. Clearly this is an ethical issue. Any thoughts on where we should to fix the problem?

[Sbrownstein]

You have 12 volt problems, probably starting with a converter that does not charge your house batteries. The loss of power sounds like you were losing 12 volt capacity. Check the converter, check its breakers...start there. The microwave is the only appliance that you have mentioned that should have worked. The AC still needs 12 volts for the thermostat as does the reefer, slides, etc.

[windsorbill]

Originally Posted by Crose55

This weekend was our maiden trip of our class a motor home. We want to go full time in a year. We headed for a state park for our first trip (close to home!). We have a 2011 Coachmen Sportscoach. it was used only 7 times with 7k miles. We plugged into a 50 amp shore lone at the site. For a while all was fine. Over the day, we kept losing power. The air conditioning worked. All GFI outlets worked fine, but no others. The microwave had no power at all. The inventor w
Irked on and off but reported a fault. The overheads lights dimmed to almost out. Then the air worked on and off. We started the generator and nothing helped. There were no tripped breakers. Then we thought we would go home and figure it out later. However the slides and awnings had no power. Roadside service couldn't find anyone to come and help. We went to bed. This morning the air worked. GFI outlets still worked but no others. Refrigerator would not switch to LP so all was wasted there. But, we pulled in all slides although they came in very slowly. Awning retracted too. Home now but we have no idea where to start. When we purchased the rig, our inspector said everything worked great. Clearly this is an ethical issue. Any thoughts on where we should to fix the problem?

Really sounds like a battery/12 volt issue. Are the batteries charged? If I get even a little corrosion on the battery terminals, things go crazy. Check all your 12 volt connections.

I don't know if you have a battery disconnect switch. They sometimes go bad as well.

[imob]

Wow ok your all over the place on that one. Based on what you are saying I can not determine source. On one hand you are describing depleted battery or 12v issues. Then on the other you are describing 120v issues where there would be no cross over... such as the microwave and AC. So ether the sequence of events are misstated or you have multiple issues.

Start with the 12v system. Check your battery conditions and connections. Clean any corrosion, make sure the house batteries are full of water, charged, and possibly take them to your local parts store to be tested. Next you should voltage test the at the converter. In my personal rig the converter just went out recently. It would power the 12v but not the batteries. I recently added an inverter for the TV's and put in a new power wire for it directly to the batteries. This exploited the lack of the 12v charge from the converter and drained the batteries.

As for the 120v issues, need more information. Based on your description it could be a number of things from the plug to the ATS to the power panel.

As I am typing this I did have an idea... If you are having a 120v input issue, and your batteries are weak/not fully charged, then it could be a cascade effect. You still have multiple issues but the root being the input 120v. Because if there is something flaking going on with an input line and that line has the converter on it then the 12v would be pulling the batteries. With the batteries being weak they would run down quickly.

When the AC went "flaky"... was it on 1 ac unit or both ac units? Did the microwave ever come on? If you look at your circuit breaker box are the things that were going "flaky" all on one side of the block?

[Crose55]

Thank you all so much. Clearly we need to find someone to help test the batteries and electrical systems. The microwave never came on. When the AC started cutting out both units were on. The coffer maker and TV both worked until the inverter fault light came on. That's when the interior light dimmed dramatically. I'm just thankful we were able to get home! Thank you again for sharing your wisdom.

[imob]

Yea this is something that if you are not comfortable working on electrical systems is something best left to a professional.

My guess though is that there is something flaky going on with your cord or transfer switch. The breaker block has 2 independent sides and I am guessing the power coming into one side has an issue.

Best wishes on getting it repaired. Remember independent mobile techs are often better, faster, and cheaper then taking it to a shop

[greenchicken]

All you need to check the batteries is a volt meter ...

Unplug shore power and test voltage on batteries
then plug in shore power and you will be able to tell if they are charging... if not disconnect shore power and start engine and check again... If they charge with engine on and don't charge with shore power it is probably a converter problem

When starting generator or using slides I always have the engine running as it supplies more power... Good luck

[Dark Sky]

Just posting so I can follow the rest of the story more easily. We also have a 2011 Sportscoach. Have only put on 3k miles and we are still learning and discovering. We have had issues and repairs but nothing electrical.

[MisterT]

I think your first check is the house battery VOLTAGE level. When the house batteries are low/depleted, it can cause many other 'issues' in the coach, even with other 120v items that run off of Shore Power.

The Charger sends power to the batteries when you are plugged in, or the generator is running. Make sure it is ON. If you have a Magnum inverter panel, check the setting for SHORE MAX, and make sure it is at least 20 to 40 amps. This lets the charger have enough of the power to recharge the batteries.

The Inverter changes 12v battery power to 120v power for you plug in type items, including the Microwave. While the inverter mostly passes thru Shore Power directly to the 120v items when you are plugged in, it could be under stress if the battery levels are too low and not getting recharged. When the inverter 'fault' light is shown, it means the batteries are too low for it to continue - causing your 120v items to shut off.
Note: The AC units might still operate since they are designed to only be used directly from Shore Power or the Generator, and do not run thru the inverter.

Also, check the LBCO setting, if you have one within the Inverter panel settings, and make sure that it is between 11 and 11.5 volts. This LBCO(LowBatteryCutOff) is designed to cut off your Inverter when your batteries fall below this setting, to preserve your ability to crank the generator when the batteries are low.

Check your AGS(AutomaticGeneratorStarter) setting, if you have one. Make sure that you have it 'ENABLED' and set to come on and start the generator when the battery VOLTAGE is low. Change the 'Voltage' setting to around 12.0 volts. This will kick on the generator if the batteries fall below this level for more than several minutes.
This is your back up power - even when you think you have Shore Power, losing shore power may not always be evident - the inverter is designed to immediately continue powering everything. Sometimes you may not even realize it until your hear the generator start up. That's a very good sign that your batteries needed charging, even if you were reading in bed, with a fan running, and the TV on, and didn't even know anything was 'wrong'!

[imob]

Everybody keeps concentrating on the 12v systems and ignoring the statements about the 120v systems. There is something flaking out on the 120v side. With out solid 120v power the 12v systems will run down.. period. Now some have a cross over from the drive engine that can top off/assist the charge of the house batteries, but if you do not apply 120v the system will run down. I am sticking with my assessment that there is an issue on the 120 side that caused a cascade run down on the 12 side.

Mircowaves are rarely on an inverter. The power spike is too high and ether needs a very large one or its own. This is typically only something you see on very large coaches.

[Dark Sky]

Upon reflection I can maybe contribute here:

-If you haven't done so, I suggest you contact Coachmen and request wiring and other technical details. I did this and received a substantial amount of information. You can call Tonya Kopsick at 574-825-8663. You will need your VIN of course.

-The quality of the park power supply could have been an issue. I would certainly complete the battery maintenance and testing and other checks being suggested, but also consider buying something to test incoming voltage at a minimum, plus some surge protection and/or low voltage protection. There is lots of information and advice available on this topic here if you aren't already knowledgeable.

Best of luck on finding the root cause and making any needed corrections!

[TeJay]

Crose55,

Poster #7 gave you good advice. No matter what you are doing or where you are going with the RV here's how to look at it. The KISS principle:Keep It Simple Stupid.

You need 12-V to run only 12 V things and 120 V to run 120 V things. An INVERTER changes 12 DC to 120 Volts AC. A CONVERTER just charges your hours batteries to run your 12 volt stuff. Some 120 volts things need 12-volts to operate the circuits.

A Digital Volt Ohm Meter or DVOM is used to check 12-volts and 120 volts and you need to learn how to use one. Your time as an RV owner will be much better if you do.

Check the Chassis battery. The chassis battery cranks the engine and there is only one.

Engine off it should read 12.6 V. If it a little less (12.3 or 12.4) that may be OK. If it's below 12 V your battery may not being charged.

Engine running the chassis battery it should be at least 13.6 V. If it's not 13.6 or higher then your alternator is not charging at all. Ours typically runs at 14.2 volts when cruising.

Engine OFF!! Now check the COACH batteries. There's usually 2 of them. Engine off and RV not plugged in to shore power (SP). Look for the same readings. Fully charged 12.6 V. If below 12 V no charging.

Now plug into SP and check the voltage. It should read 13.6 V or more. If it does then it is charging (or trying to charge) the coach batteries. If not then the CONVERTER is not charging the coach batteries.

The CONVERTER probably uses the engines running alternator to recharge the coach batteries through the converter when driving. This I'm not to sure about but it makes sense that it does. When we get to a campground we have never had low or dead coach batteries and we used 12-V while traveling.

That's really where you have to start to determine your next step. To do anything else is not following normal troubleshooting steps. You first have to determine where the problem is before you start anything else. Don't remove anything don't replace anything or you're wasting your time and may or will make a mistake and replace something that may be OK.

With some RV's the Converter will charge both the chassis (cranking) and the coach batteries. Ours is a 2014 WBGO product and unless I'm driving the chassis is not being charged. If I'm plugged into SP the converter charges only the coach battery and not the chassis batteries.

If your converter is not providing a good charging voltage of at least 13.6 volts then it must be fixed or replaced. Yes your coach batteries may be defective but that is separate from knowing if the converter is even trying to charge those two batteries. If the coach batteries have not been charged because the converter is bad that's why they may be bad now. It's not because they were not good at one time. They may have been discharged for a year or more a, not being recharged by the converter and now they are bad. First things first.

Sorry if I repeated what has been posted since I started my response (right after I read #7's response and then three others posted just before mine.

[imob]

Originally Posted by Dark Sky

Upon reflection I can maybe contribute here:

-The quality of the park power supply could have been an issue. I would certainly complete the battery maintenance and testing and other checks being suggested, but also consider buying something to test incoming voltage at a minimum, plus some surge protection and/or low voltage protection. There is lots of information and advice available on this topic here if you aren't already knowledgeable.

That is actually a VERY good point. If you have the rig plugged in at home and did not see any of these issues then it was probably an issue with the park power! On the other hand if you still see these flaky issues at home then there IS something at hand.

I do not think you mentioned if you tried it on pure gen power or not.

Sometimes the most obvious are the easiest to overlook! Good one Dark Sky