Inverter Issue

CarpeDiem · 04-02-2020, 08:34 AM

We have a 2020 Winnebago Sunstar 29VE. Today the CSW 1012 inverter started making a beeping noise. Following the instructions, I found the readout showed E01 for a moment then E05. I plugged in a space heater in this morning and this stared after that. (I’ve used the heated one other time with no issues). I’ve reset the inverter several times and each time the problem persists. Of course,I’ve got very little load on the system and the batteries show to be fully charged. Any suggestions?

powercat_ras · 04-02-2020, 08:51 AM

Beeping indicates low battery warning, inverter will shut down eventually after battery voltage falls further.

E01 is a low battery voltage inverter shutdown alarm, triggered at battery 10.5 volts

E05 is a low battery warning alarm, battery at 11.2 volts.

Likely just batteries needing to be recharged, but you can wiggle all the battery connections on the batteries and inverter and any in-line fuse and tighten if any are loose.

CarpeDiem · 04-02-2020, 09:04 AM

I did read that in the manual, but as the coach is new I didn’t think that would be an issue. I checked the cables and they are all secure. The coach indicates the batteries are fully charged. Anything else I can check? The coach has been plugged into shore power for the last ten days.

Morich · 04-02-2020, 09:11 AM

Don't know the coach and don't know the heater but I might ask if the heater is using more power this time than the other times used. Does it have two settings? A 1500 watt heater draws about 12 amp on full setting and that is quite a lot of power when used full time, so it will work heavy on the batteries.
It is easy to get mislead by a simple battery voltage check as we often get a "surface charge" which does tell the true state of the battery when we want to use it. We can get a "full" reading if we look at the voltage but we need to wait at least an hour or so to get the true reading. It takes something like 70+ hours to actually get to the full point of charge.
It was plugged in for ten days, but what is the history before that? If the batteries were allowed to go totally flat, it is possible they are damaged and one way for that to happen is during storage.

Winterbagoal · 04-02-2020, 09:19 AM

Quote:

Originally Posted by CarpeDiem

I did read that in the manual, but as the coach is new I didn’t think that would be an issue. I checked the cables and they are all secure. The coach indicates the batteries are fully charged. Anything else I can check? The coach has been plugged into shore power for the last ten days.

Is the breaker for the converter/charger enabled? Check the power control center, wherever it's located and verfiy the status of your breakers and fuses. 10 days on shore power should bring the coach batteries up to full. Also, try disconnecting shore power for a while, before you test the batteries. As Morich said your One Place monitor might be reading charging, not resting, voltage.
If you have a multi-meter, check the batteries at the posts. If not, get one.
The inverters don't usually lie. If it says low input voltage, it probably is. You need to figure out why.
After thought: Did you buy off a lot, or order a new build? If the former, the batteries may be suspect. Dealerships don't usually take care of them on the lot.

**creativepart** · 04-02-2020, 10:15 AM

An electric heater is by far the highest inverter load you can put on a battery.

This load is so large that:
1. It will use up battery power in a very very short time, possible minutes.
2. It will likely demand more amps at one time than can be delivered by the batteries.
3. It will trigger low voltage cutoff even before the batteries are drained due to the severe voltage drop as the amp demand is far too high. All batteries have a set discharge rate. They cannot simply put out unlimited amperage instantaneously. Lead acid batteries have lower discharge limits than newer AGM and especially Lithium batteries. But even Lithium batteries do have limits to how many amps can be drawn at any given time.

So, all these are possible with a full battery bank - new coach or old coach, new batteries or old batteries.

Anything with a heating element in it is automatically considered a heavy load for an inverter. Hair dryer, coffee maker, electric griddle, electric water heater and especially an electric space heater, even a small one. Other large draws are microwaves, A/C units and any heavy duty high torque motor driven device.

Lastly, if you are judging battery state of charge (SOC) from your battery voltage meter on board your RV it is highly likely that you are getting false information. Battery voltage meters are totally inaccurate if a) there has been any charge applied to the battery within the past 30 mins, or b) if the battery has any load on it at the time of the reading or immediately after a load is removed.

The only accurate way to know your battery's SOC is to either not use it in any way, either to apply charging or to draw current from it for 30 mins. OR to use a different kind of battery monitor such as a shunt-based Battery Monitor.

CarpeDiem · 04-02-2020, 10:35 AM

This started at about 9am this morning. The issue is ongoing, all other electric including the a/c is working fine. I haven’t tried unplugging from shore power yet. I don’t currently have a tester, obviously that’s my next purchase but trying to stay put as much as possible. Thanks for the advice.

**creativepart** · 04-02-2020, 10:50 AM

If you are plugged into shore power then your converter/charger is busy charging your overdrawn batteries. Probably working very hard at that. If you are also running AC and other large loads your converter/charger may take a very long time to recharge the batteries - as in 24 hours or even longer.

Most stock converter/chargers don't offer very high levels of charging and your RV's electrical distribution system will attempt to moderate charging to accommodate the demand for A/C usage. If your water heater is on electric that can increase your charging time dramatically as well.

If the inverter is still beeping, simply turn it off completely. The next problem will be how to know when your batteries are fully recharged. As I pointed out previously, you can't rely on ANY voltage meter unless you unplug from shore power, turn off EVERYTHING like you are putting the RV in storage and waiting between 20 and 30 mins before taking a reading.

Assuming they were discharged below 12v they can realistically take more than 24 hours of continuous charging to be returned to full 12.6v - 12.7v.

Your converter charger will charge your batteries in 3-stages. First, it will apply high voltage/amperage BULK charging. But generally not for a very long time because it isn't capable of it and neither are your batteries. Next it will go into a very long phase of ABSORPTION. This is the part that needs a very long period of time. Then once your batteries reach 80% of full charge your charger will enter FLOAT stage and it can and will take days of Float charging to finish that final 20% to reach a full charge.

CarpeDiem · 04-02-2020, 10:58 AM

I appreciate the words of wisdom. Actually, that is much better news than, “OMG, get to a repair shop ASAP”

**creativepart** · 04-02-2020, 11:07 AM

I'm assuming your newer RV came with AGM batteries. If it did not and you have flooded batteries (with caps that are removable, that require you to add water) you can test the battery cells individually with a hydrometer without worry of getting a false reading.

AGM or Maintenance Free Sealed batteries can't be tested this way.

Here is a GREAT resource for learning all this battery stuff quickly:

The 12volt Side of Life (Part 1)

powercat_ras · 04-02-2020, 12:17 PM

If you are plugged in TURN OFF THE INVERTER ! There is likely a cut thru transfer switch and the outlet will still be hot even with the inverter turned off. If not then plug the heater into another outlet that is powered when the rig is plugged in.

If you have a electric heater plugged into an inverter fed outlet, the inverter is drawing more DC amps when the heater is running (50-90 amps) than your AC powered battery converter charger can put out (35-45 amps DC). You will slowly run down the batteries even when plugged in IF you try to power your heater off the DC to AC inverter rather than directly off of AC power.

Morich · 04-02-2020, 12:49 PM

I see the inverter on one serial number of your RV as being 1000 watt, so if the heater is using 1500 watt, that is one obvious problem. There should be some indication in the manual or in other info of which outlets are from the inverter and which are straight from the shore power/load center.
If this outlet is the only one in the area you want heated, a second alternative is turning the heater down to a lower wattage. If it is the type I think of there are two settings, one 750 and high as 1500.
When on shore power, I would have "assumed" there would be a form of transfer switch in the inverter to allow using straight shore power at all outlets, even though which work through the inverter when not on shore power.
New units do not have wiring diagrams listed which are good enough to actually see how it is wired, so some guessing/checking is needed to find out what they actually do.

**creativepart** · 04-02-2020, 01:39 PM

The overriding advice we all can provide is to understand your batteries, your inverter, your converter/charger and your whole electrical system.

We don't know if your coach is 30 amp or 50 amp. We don't know if you have an RV Fridge or a Residential Fridge. We don't know if you have 2 house batteries or 4 house batteries. We don't know if they are Flooded Lead Acid or AGM. We don't know if you're plugged in to a 15a, 30a or 50a shore power outlet, either.

If we knew all of these things it would help us help you even more.

We do know you have a 1000w inverter. So, we know that there are many limits to what that device and do for you. It's vital that you find those limits as well.