PDA

View Full Version : Learned something about inverters the hard way ....



Ray Davis
08-11-2009, 03:19 PM
I recently had to vacate my hangar where the bus was stored because the owner sold it. We had installed 50A power there, and it was a great place to stay.

Anyway, found an indoor RV storage solution out near Lake Perris at a pretty reasonable cost (for CA standards), and after spending a week in the bus out at Rancho CA, I put the bus in it's new home.

Because it only has a 15A circuit, I dialed down the inverters and left the bus. 4 days later, I decided to go back out to the bus (1 hour drive), to check on a video issue I had seen on my previous trip. I arrived to find the bus dead as a doornail, with the storage sites external circuit breaker tripped.

Evidently the night watchman at this site had been trying to plug in a personal air conditioner in a garage 2-3 down from me, which evidently shared the same 15A circuit. Evidently he popped the breaker a number of times (according to the manager), and they ultimately ran him a long power cord from another unit, but unfortunately, they left the breaker in the "broken" position, and my coach inverted itself to death over the 4 day period. (Refridgerator was on).

I was able to fire up the coach and the generator and start the batteries charging. I understand later, talking to Marathon, it would have been better to not start the bus and hit the batteries with 270A of charging, but anyway, that's another story.

Anyway, on to what I learned about the inverters. I hope this might be instructive to others. (This is on a Trace inverter)

1. There is a charge-only setting on the inverter panel. Rather than selecting "On", select "Chg", which is the far right menu entry. According to the manual what this does is pass A/C through, charges the batteries, but IF the external power goes down, it does not try to invert. It specifically says it's to handle the case where public power goes down.

If I had used this setting, I would have lost the food in the fridgerator, however I wouldn't have damaged my batteries.

2. When I tried to dial both inverters down, and set them into charge mode, the aux inverter kept resetting, on/off. What I finally surmised is that besides setting down the input cord size (amps), you may also need to turn down the amount of amps available to the charger (battery charging menu, #10)

Ultimately what I did was turn the aux inverter off, and set the input amps to 12A. Then I dialed down the battery charging amps to 10A, and this then was safe in bringing my batteries back up.

A couple of other things, based upon previous discussions regarding the charging time setting on batteries. We've had discussions that for many of us who do not boon-dock, we could turn down the bulk charge time from the default of 3 hours to something less.

As it turns out, I don't think this is really necessary. What I discovered after watching the charging voltages and amps very closely over a couple of weeks is that although the inverter will be in bulk charge mode, the actual current charging will be limited by the batteries need. I.e., if your batteries are fully charged (like you just drove 100 miles), then even though the inverters indicator lights will show bulk charge, although they may only be actually trickle charging at that point (on the order of 1-2A).

It is my guess that the bulk charge timer value as set in the battery charging menus is used as a fail-safe, that after the appropriate amount of time, the charge will go to float mode, whether or not the charger was charging at full bulk mode. I think this is a safety to prevent a bad battery from causing bulk level charging to happen over long periods of time.


Obviously our coaches can all be wired in many different ways, but I found that turning off the aux inverter/charger, I was better able to regulate the charging current (because of the darn 15A circuit), and all the batteries were still being charged.

Please note if you do turn off an inverter, when it is turned on, it comes back at default settings, so it's expecting a 50A shore cord, full-rate charging on batteries etc, so you may need to dial them down to fit your particular needs.

For those of us who don't have 30 or 50A power available at a storage site, using the "charge-only" setting may help you from destroying a set of batteries. As we know, it costs somewhere around $3500 to $4500 to replace a full set of coach batteries.

ray

Jon Wehrenberg
08-11-2009, 04:52 PM
If I had to have my coach in a remote location I would definitely set the bus cell phone up with some device to phone and warn of a power outage.

Ray's suggestions about setting the inverters up to stop inverting is an excellent suggestion, but perhaps the best approach of all is to put the entire coach to sleep but killing all power from both chassis and house batteries and visiting the coach as often as required to recharge the batteries. To shut down my coach only involves several shut off switches, and a fully charged set of batteries will last a long time before requiring a fresh charge.

GDeen
08-11-2009, 05:32 PM
Ray, sorry for your troubles, but thanks for the info. I have set one charge limit setting to 30 amps, but need to set the other to the same limit. Has been on my list of things to figure out as when I first go from driving to shore power, the invertors throw massive current to the batteries at the same time I am trying to start cruiseairs. Doesn't last long, but many times it kicks out the 50 amp Marathon aux reset. Didn't know why it was still happening since I had the input set to 30 amps, but you have answered that question.

I also learned what you have surmised about the bulk charge mode. The current to the batteries goes down as they charge even though it is still in bulk mode. So the time doesnt' really matter before it switches to float as they take whatever they need to charge anyway. By limiting max charge input to 30 amps or so, I can avoid the peak demand shown when first switching over, and won't worry about the 3 hr bulk charge setting. (please let me know if I am missing something).

The problem I have with letting the coach sleep is that it is 105 degrees outside and the bus storage is not much cooler. I am fortunate enough to have 50 amp service so I can run a couple of the cruiseairs at 82 or so to keep the interior from getting too hot. Have worried about the breakers kicking out and the batteries going down quickly in that situation. Sounds like the "charge only" option you discovered is a good solution to save the batteries.

Ray Davis
08-11-2009, 05:49 PM
Hey Gordon,

Yeah, as you've noticed, you have to generally lower the charging settings on both inverters. IN the case of 50A, you should actually have 2x50A (50 on each leg), so setting each inverter to 30A should be fine. You could probably set it lower without much issue, as I assume you are like I am in that you don't generally boondock and need to charge at 60A total.

In the case of a 30, 20 or 15A plug, that's all you got, shared on both legs, so both inverters need to be cut to half of that. Plus, as Jon has mentioned (I believe) in the past, you really only want to use about 80% of a rated circuit, so when I set mine recently, I limited to 12A on a 15A circuit, with the second inverter turned off.

Jon, I have been trying to think of a way that I could easily get status reports from the bus. It would be great if there is some device that would send an email or text page when power went out? I don't know of such a device, but it seems like a useful gadget. Unfortunately, that seems to indicate it would need to either have a cellphone internally, or access to a wifi to send message? Generally hard to come by at a remote location.

Ray

GDeen
08-11-2009, 06:09 PM
Hey Ray,

I turned down the input amount to both inverters, but need to also limit the charge amount in menu 10 as you said. With only that one limit set, they are still throwing max current to the batteries.

Jon Wehrenberg
08-11-2009, 07:29 PM
Ray, As most have figured out by now I usually do not embrace technology.

However there are alarm monitoring services that have devices to report power outages. Our bus has a cell phone hard wired into the coach. With battery backup for standby power anytime the power in the storage building was shut off the cell phone could automatically dial a preset number and electronically report the outage.

I don't know how it functions or where to find the devices, but I know it can be done. A monthly phone service charge is chump change compared to a set of batteries that need to be replaced prematurely.

JIM CHALOUPKA
08-11-2009, 07:50 PM
Hey guys, used an X 10 product some 20 years ago to turn on heat at our weekend farm house prior to our arrival.
Maybe you can think of a way to hook one up for your purpose.
Back then they were found at some Radio Shack stores too.
Here is a link to them with many ideas and variations.

http://www.thehomeautomationstore.com/?GG042508x10gener4&gclid=CPnR48fknJwCFYZM5QodWyjGew

My use required an old fashioned land line phone.

Hope this helps

JIM

truk4u
08-11-2009, 08:11 PM
Just to add some caution, when only on 30 amp service, if you leave both Trace Inverter/Chargers on, you have to set them on 15 amp each, not 30 each. I learned that lesson when trying to use 15 amp once and quickly found that each had to be set to 7.5.

Ray Davis
08-11-2009, 08:21 PM
Exactly. On some of the Trace inverters there is a setting in menu one for "shore cord size", which you set in amps. I was under the assumption if I set this to let's say 10A, then the charger would not try to charge at more than 10A. I'm not 100% sure that this works all the time, and I found it best to manually set the inverter charger down (menu 10) in addition to setting shore cord size.

Some inverters do not have the "shore cord" menu option, and instead you have to set AC Grid Size in menu 11.

IN either case, as Tom indicates, on a 30A or 15A circuit you must divide the power settings between both inverters to total no more than the circuit will allow.

jello_jeep
08-12-2009, 12:15 AM
If one so chose, you could put in a small alarm panel at your storage unit, and hook up a cellemtry unit to it.
As long as you plugged in the transformer into a receptacle that shared the same circuit as the bus, you can program the panel to send a signal when the ac is out for whatever time period you program the panel to look for.
The panel could have whatever size battery in it you want, common size would be 7AH.
If there is a phone line available (POTS) you could hook onto that, or use the cell device in the absence of a regular line.
You can also hook up any other device to it that will open or close a circuit, (normally open or closed switches) be it for a door, a water sensor, Co2 sensor, temperature sensors etc.
When the signal is sent to the monitoring station they would do whatever you wanted with the signal, namely call you or whoever you have on your list and report the condition in question.
I would guess most alarm places would charge about 20-25 bucks a month to monitor it if you have a pots line, more if you require cellemetry too (as it requires two accounts). Most companies would require a contract of 2 years (ballpark) to set it up too, so it could be costly if you are not sure you are going to stay there.
Bigger places (ADT, Brinks etc) wouldn't even do it if you didn't own the building (best of my knowledge) you would have to find a smaller mom/pop local place and explain to them what you are trying to do.
Radio Krak used to make a dialer you could record a message on to make calls when a set of contacts were closed or opened, I don't know if they still make it but then you would only have the cost of the pots line as far as mothly fees.
It would be impossible to make it work with a cell phone to the best of my knowledge.

MangoMike
08-12-2009, 08:27 AM
Although I have not tried this unit.

$71.99 Needs telephone line.


http://www.diycontrols.com/product_info.php?cPath=75_148&products_id=494&osCsid=bf83a188cc53f9753b5a0c634ae462ee

Automatically Calls up to Three Phone Numbers when Freezing Temperatures and/or Power Failures Threaten Your Home or Cabin.

5248

GDeen
08-12-2009, 09:19 AM
Would love to see a seminar by Trace on the inverters and what customization options are available given different situations....

Ray Davis
08-12-2009, 11:53 AM
Mike,

That unit looks interesting. Now, if I only had a phone line there. I'll have to talk to the owners and see what might be possible.

gmcbuffalo
08-12-2009, 07:49 PM
Ray if you are sharing a 15amp circuit with out units you maybe in for more problems down the road.

Have you thought about having a second powerline installed with 50amps and billed to you?

GregM

Ray Davis
08-12-2009, 09:06 PM
Yes, the management is looking into the cost and will let me know. I'd be happy with a 30A service, but 50 would be ideal.

That handles "some" of the issues. It turns out the entire region had a 9 hour power outage around the same time. Plus, my surge protector gadget has recorded at least one low voltage event since this all happened.

Sheesh!

Jeff Bayley
08-28-2009, 05:12 PM
I haven't thought this through all the way, but what about putting a lap top (you probabley have a spare sitting around) and if the storeage has reception to Wi-Fi that they would let you access, you might be able to put Magic Jack for $20 a year that could be configured to dial you if the lap top lost power. ???? (maybe someone who writes code at Pixel could make a short custom code to do the trick ?) Maybe Mango's recommended device would parlay and cooperate with it to make the call over the lap top through the Magic Jack. Again, I haven't thought it all the way through but food for thought maybe. The magic jack needs to plug into a router I think (I have Vonage, not Magic Jack and it goes into the router). If you could pick up a Wi-Fi signal and get them to give you the Web Key, it might work. If not, a Verizon or equivilent wireless card could work maybe but don't know if the band width would work for VOIP. I think T-Mobile used to have a wireless service for $30 a month. My Verizon is close to $70 I think. Wait, if you use a Verizon card anyway then it won't matter if you leave it on the bus when your not traveling as regars needing to buy a dedicated card and seperate service. Koo Koo.

truk4u
08-28-2009, 09:02 PM
Jeff,

I tried Magic Jack and it sucked. I tried it through my laptop while on Wi-Fi and the delay in speaking/receiving was terrible. It might work fine when hooked direct to a computer or router.

Jeff Bayley
08-29-2009, 02:14 PM
Tom- I don't plan on getting one right now but I did speak to a friend just the other day from his home computer and broadband that had the Magic Jack and it was perfect. But with practically everyone using a cell phone with nationwide calling I don't see the what the draw is for free long distance. It's good if you need to call internationally seems to me. With Vonage, I have a local number for Mexico that allows them to call me without long distance to them. Magic Jack doesn't offer that.

Ray- I got another product for you to look into and see if it could work for your no power alert challenge your trying to solve.

Found here: http://www.victronenergy.com/chargers/skylla-24v-48v
Battery Alarm- An excessively high or low battery voltage is indicated by an audible and visual alarm, and a relay for remote signalling
(end description)
I don't know details on the remote signalling (wired ? Wireless alarm?) . Let me know by email what you find out about it. I tried doing some more searches to get details for a few minutes and you'll have to dig deeper as I could not find anything. Maybe it has a short range wireless alarm that would work for those of us that keep the busses at the house.

Here's another possible: http://www.firemountainsolar.com/meters.html

For anyone needing a converter for the air TV antenna to pick up digital now here's a sale on one with a coupon code or something. A post I read on another forum said they walked into Radio Shack with the coupon and got it for $45 bucks somehow. Might want to phone RShack first.

On that subject, I'm about to put a new sattalite dish and when I do I'm going to put a digital antenna instead of converter. Anyone checked out what the best one for our buses is. Prefer one that doesn't have to retract.

Ray Davis
08-29-2009, 05:48 PM
Thanks Jeff,

I think my simple solution will be that I am going to have 50A dedicated service installed. At least then, I should only lose power if the power in the whole area goes down. It will also allow me to keep my fridge running when stored etc.

Ray

Jeff Bayley
08-31-2009, 06:58 AM
One final comment on the power managment and then a question on my own. Hope Ray doesn't mind me jumping in here to keep from cluttering up the forum with a new thread since it's inverter related.

For Ray and you may knw this already: If you set the inverter (that's not on the fridge) to "off", if will draw less of a load on a 15 amp cord if that's all you have I believe. Even if your not running circuit that is tied to that inverter, the inverter itself is drawing power by virtue of being in the "on" posistion I have learned. Is there anything wrong with just letting one inverter keep your batteries up on trickle and leave the other one off ? I don't think there is.

My inverter questions which is about beat and time for a pro. I'm still figuring out my one inverter that is out but today I'm hoping to drive it to an RV Electrician to get help finally. But yesterday, I went out and tried one last thing. I disconnected the serial port connector that runs to the remote from the inverter for a minute to see if this would somehow reset the inverter remote. Power to the remote went out as I thought, but no fix. What did happen was that the display on the remote (Trace, new style) was now mucked up. Only the first of two information lines was doing anything and the bottom 2nd line was bland on all 1-10 modes. The first line was still legiable but had lines through it (best I can describe). I disconnnected again from the inverter and left it disconnected not knowing if it could b bad to leave it like that. That inverter hasn't been doing anything for weeks now anyway except the "inverting" light is on but it's not invererting. None of the circuits on that inverter are operating. I failed to press the reset button. It's 6am and dark out so I'll go out there later and try the little red reset button on the inverter remote. I'm also going to try putting a new J class 350 amp fuse which I should have done a long time ago. It was ohming out ok but I'm going to change it just to double check.

Further question; are there any connections at all behind the inverter on the rear ? I don't want to go removing them to see what might be back there for wiring / connections if there is nothing there.

I need to get the installatin and/or owners manual for the RV Electricians tech's reference if possible. If anyone has this in PDF and can email it tome at jeff@skincarepro.com much appreciated. I checked Xantrex's site and no luck. Over the phone, he said he thoght the internal transfer switch on the inverter itself might be bad. Didn't even know there was one inside the inverter.

Here's a couple photos of what I have including the model number. I checked the connections at the juntion box you see open and they felt solid although I didn't unscrew and reset them. Notice the unlit red LED in the top of the open panel: I've asked a few times about this light not being on but no answer however I think the short answer is that it means no power going into the inverter (or maybe a component out inside the inverter): Here's the details and quote I posted prior as it relates to the light:

On the Trace 2,500 watt inverters (the inverters/chargers themselves, not the remotes), there is a small, removable panel on the front upper right hand side. Behind that panel is a small factory installed jumper with an LED light next to it. It is labeled "Utility line TC test. Remove to disconnect A/C1 In relay. LED simulates relay operation". If there is an A/C1 relay somewhere I don't know where it located. Could be referring to the automatic transfer switch which appears to be working however the symptoms on both gen and shore power remain constant so if it's the relay in the transfer switch it would have to mean that both the gen side and the shore side of the transfer switch are both deffective on the 110 leg going to that inverter which is possible but unlikley. I checked this light a week ago and it was in fact illuminated along with the AC1 IN Good light on the remote being illuminated. Now they are off. Symptoms from before and now unchanged however.

>>>>>>>>> I don't know how I could have over looked the obvious yesterday to check these input and output terminals on the block with a multi meter but it's light out now so that's exactley what I'll go do now.

Ray Davis
08-31-2009, 01:36 PM
Jeff, Off would indeed work, if I didn't want to keep my batteries charged. At several thousand dollars for a set of coach batteries, I don't want these puppies going down, and I'm not close enough to monitor closely.

Ray

Jon Wehrenberg
08-31-2009, 02:38 PM
If I had to park my bus in a remote location for extended periods I would put the whole thing to "sleep".

I would fully charge the batteries and then turn everything off inlcuding the batteries, going so far as to disconnect cables if necessary.

I would support the chassis on stands and at the very least dump the air in the air bags so only the weight of the axle is on the tires. I would open all the doors in cabinets and refrigerator, open the roof vents, crack some windows, and make sure the water and waste tanks are empty, and water pressure is zero.

Then, until I knew for sure I would check battery voltages daily, then weekly just to know I won't return to dead batteries. Once I was confident the batteries would hold voltages OK, then once a month would likely be sufficient to check up on things.

I would not run the engine until I was ready to drive somewhere, but I would run the generator to recharge the batteries and bring them up to full charge each month. I would treat the fuel with a stabilizer for fuel in storage.

Bottom line however is having a bus close at hand and always hooked up to 50 amps is priceless and I would do whatever it takes to do that. There is too much value, both real and emotional to keep a bus at a remote location.

Ray Davis
08-31-2009, 03:29 PM
Unfortunately, there are reasons that won't work in my specific case, or at least some of the suggestions won't work well.

Nearby indoor storage is impossible. It basically is almost non-existent anywhere near by me. The one site that does have indoor storage is completely full and want's on the order of $600 per month for that storage. Other semi-close storage options (within 30-45 miles) are valet only.

I was lucky to find individual RV storage garages out in Lake Perris, which is exactly a one hour drive for me at $300 per month.

The power is an issue, but they have agreed to let me pay for 50A power to be installed, but they will not charge me more for it's use.

I did try the generator one time. Within 10 seconds the CO2 alarm was screaming etc. These garages are only 14 foot wide, and the ceiling is probably only 10 foot overhead, if that much)

So, for me the best solution, at least for now, is get 50A individual power circuit installed, so I am not worried about a shared 15A plug. I do try to get out about every two weeks, max. About every month to 6 weeks, if I haven't been out on a trip, I take the bus out and drive it.

I guess another suggestion might be to shut the bus down completely, but get a couple external tender/trickle chargers, one for the coach, and one for the chassis. At least, if they power goes down, I won't have things trying to invert itself into oblivion. The seems effectively what I've done now anyway, as in the Charge position, if power goes out, it will simply stop charging, and not discharge the batteries.

Ray

Jeff Bayley
08-31-2009, 03:51 PM
Jeff, Off would indeed work, if I didn't want to keep my batteries charged. At several thousand dollars for a set of coach batteries, I don't want these puppies going down, and I'm not close enough to monitor closely.

Ray

Ray- I just meant to turn off ONE of the inverter/chargers and leave the other one on 5 amps or so. That way you reduce the overall draw on the 15 amp circuit in case the other bone head puts a heavier draw on it at least your part would be lower overall. You batteries can float with just one inverter on.

Ray Davis
08-31-2009, 04:12 PM
Sorry Jeff, I misunderstood. Indeed, that's what I did to get the batteries back up and charged.

They are both back on in the charge mode now, but limited so that things cannot overcharge, thus blowing the circuit.

Ray

Jeff Bayley
09-01-2009, 07:24 AM
Ok, but I still think turning one to the off position and leaving only one on the charge or on position (the one running the fridge if you care to leave that on), makes less load. I found out when I was using my 3,500 watt aux generator for over night dry camping as many of you know I use to sleep w/o fear of a generator fire. No matter what I did to adjust the inverters down it kept tripping the fuse on the small generator until I finally turned one of the inverters to "off". That lightened the overall load sufficient to make it hold and work.

Jeff Bayley
09-03-2009, 01:31 PM
I'm throwing this up here so POG'ers have two chances to see what could have been an electrical fire in case the other thread I started calling for Roayle help get's glossed over: I don't think there's anything we can do to avoid this particular wire fry but wanted to share it none the less. Since I can't provide a wealth of difficult technical answers, I'm limited to contributing what bafoon stuff I can in an effort to try and pull my weight.

Here's the link to see the pictures and explanation: http://forum.prevostownersgroup.com/showthread.php?p=53392&posted=1#post53392