Inverter problems

[kernr]

Good Morning - I am new to the forum and have been impressed with the tech answers given to the questions asked.

We transitioned from Sail boats to trawlers in 2020 and I have to say these trawlers are a lot more complex when it comes to different systems then any sailboat I have ever had. In Feb 2020 we purchased a Grand Banks 47 Europa in Miami, FL. I have had a few minor problems with her that were not difficult to fix (you know just time & money) but for the most part she made the trip from Miami, FL to Newport, RI without and major problems.

Since our marina has been closed until June 1st we have been sitting at a dock without power and I have been running the generator every third day or so to keep the batteries charged up. Well yesterday after charging and shutting down the generator I placed the Inverter Bypass switch from "AC Main" to "Inverter" and the inverter showed no yellow light indicating that it was available to make AC power - even though there were no AC loads. No matter what I did at the Inverter remote panel I could not get the inverter to change modes and come on. I looked at the inverter itself and the panel was blank. When I cycled the inverter switch to off and then back to on the inverter showed a bar type activity and then eventually goes blank. I thought there is supposed to be a fuse prior to the inverter control switch but I am not sure where it is (possibly in the control box). So never having had an inverter I am ignorant about what is causing the difficulty. I have a call into a recommended marine electrician but this is a tough time of year to get their attention and no response yet. The inverter is original Xantrex inverter/ charger and it performed well coming up from Miami.

Any suggestions of things to look at without getting in over my head would be appreciated. Thanks, Bob

 

[O C Diver]

If you see information on the display before it goes blank, it would seem unlikely that a fuse has blown.

In a similar situation in the past with a different inverter manufacturer, I was advised to power the unit down and disconnect the negative 12 volt power lead, wait 5 minutes, reconnect the lead and power it up. It's like rebooting a computer, and it worked. Something to try anyway.

Ted

 

[Russell Clifton]

What OC Diver said. I too had to reboot my inverter awhile back. Found the procedure in my owners manual.

 

[tiltrider1]

The picture you have supplied shows the inverter has battery power but is not turned on. There should be a “_” under the “on”. Press the green button until the “_” is under “on”.

 

[kernr]

tiltrider 1 - So the picture was taken when there was a read out on the remote for the inverter, however, even at that point in time I could not get the "_" to move anywhere or bring up any of the menus. Now there is nothing on the display.

Possibly I should try to do the reset others are referring to - I will check the manual for this inverter and see if it references a reboot type action.

Thanks,
Bob

 

[porman]

I have had to remove power to reset my Xantrex inverter twice. Left the power off for an hour and it started right back up.

 

[kernr]

porman - Thanks, did you just turn the battery switch off or like was previously stated you disconnected the negative from the inverter? Bob

 

[kernr]

I took a picture of the inverter control panel next to inverter and the name plate on the inverter - see attached. My Xantrex Manual does not reference a power disconnect. Bob

 

[O C Diver]

I took a picture of the inverter control panel next to inverter and the name plate on the inverter - see attached. My Xantrex Manual does not reference a power disconnect. Bob

If that switch disconnects the power from the inverter, that would be fine to use. You will know the power is off as both the display and the remote panel will be blank regardless of what button you press.

Ted

 

[porman]

porman - Thanks, did you just turn the battery switch off or like was previously stated you disconnected the negative from the inverter? Bob

I just turned off the battery switch.

 

[tiltrider1]

I am now concerned that the bypass switch might be faulty. I would start testing for voltage on both sides of the switch.

 

[gsholz]

Check your batteries. Can they carry a load? If you have been charging them with only the generator for a month, it is likely that they were never fully charged and could now be sulfated. If the batteries are flooded lead-acid, it would take 6-8 hours of generator time to get them to 95%. The last 20% are painfully slow.

 

[twistedtree]

If no display on either the remote or the display on the inverter, you probably don't have any DC getting to the inverter.


Pop off the cable end covers and measure the voltage across the two big terminals on the inverter. It should be 12-13V. You probably have none. From there you will need to work your way back from the inverter to the batteries to see where connectivity is being lost. A high-suspect device would be the rotary disconnect switch. There also should be a fuse somewhere near the battery.

 

[kernr]

gsholtz & twistedtree - Thanks for weighing in on this topic - appreciated. I have checked the battery, as well as, the battery cables for tightness and no extra washers etc on terminals - they were good and the 8D battery that is stated to be the inverter battery is showing 12.5 VDC. Which brings up another question in my mind - is there just one 8D that services the inverter or are the two house batteries and the one inverter battery, 3 8D batteries, all in parallel and available to the inverter to make AC? It seems like one 8D wouldn't be enough capacity.

Regardless, back to the inverter, I like the idea of checking back from the inverter to the batteries. I will first check the terminals on the inverter side for DC Voltage. That should tell me with 12.5 at battery and something like 12.5 at the terminals on inverter that it is an inverter problem or a connection / fuse / disconnect problem back to batteries. I'll get on this today and report back what I find.

Any thoughts about the "Inverter Bypass switch at lower helm - can that be causing some of this problem.

Thanks again for your thoughts and assist!!

Bob

 

[Kapn]

Those inverters that I’ve seen should charge when they see AC power from shore or generator and then immediately invert when there’s no AC from shore/gen. The AC always goes through the inverter to the AC panel.
The bypass switch’s are usually there to keep AC from going through when there’s a issue.

 

[gsholz]

The bypass switch just allows you to connect the outlets downstream from the inverter to shore or generator power should the inverter die. It does not impact the DC side. First step is to measure voltage on the DC input terminals of the inverter.

One caution is that digital voltmeters are very high impedance meaning they do not put a load on the circuit. This means sometimes you measure "phantom" voltages. Better DVMs have a low-Z mode (low impedance) to prevent that. Or you can just use a 12V bulb to put a load on the circuit.

 

[twistedtree]

Humm, depending on how that bypass switch is wired, having it set to "SHORE" may remove shore power AC input to the inverter, and hence defeat it's charging capabilities. It makes me wonder if you haven't inadvertently completely discharged your inverter battery(ies). It would explain a lot, if not everything you are seeing.


BTW, you "Blue Book" that came with the boat has wiring diagrams in it that might help. I owned 47EU #76 and it had the bypass originally wired to only switch the inverter output, but I re-wired it to switch the input as well so the inverter would be de-powered when bypassed. Kapan is correct that the bypass switch should seldom if ever be used.

 

[tiltrider1]

The Xantrex inverter is actually a rebadged Trace SW2512. A truly ahead of its time inverter charger. Normally both the generator and the shore power would be wired straight to the inverter AC1 and AC2. I have seen bypass switches before but they were set up to bypass the inverter if the inverter failed. However the inverter would be unable to charge a battery if it was bypassed. I’m not sure what the bypass switch is really intended for in this application. I was rushing when I made my last post and it didn’t come out correctly. As Twisted mentioned above I was wondering if there is confusion on what the bypass switch is doing.

First I would check the battery voltage and then follow it to the inverter. If the inverter has 12.5v at its terminals and still no screen info then we know it’s an inverter issue. At this point I am less likely to suspect the inverter as they have a great reputation. My old boat has the SW2512 in it that was installed 25 years ago and is still running problem free.

 

[kernr]

Hi everyone - So I guess we have the great Inverter Bypass Switch question as to what it does and how to properly use the switch in accordance with the design. i have to admit that since the boat is fairly new to us I wasn't sure so I asked two different Marine electricians. They both stated that the switch should be in the Inverter position when the external source for AC power (SP or Generator) are not present and when you have a SP or Generator AC source then the Bypass switch should be in the AC Main position. That being said I will tell you that a charge to the batteries is taking place when in the AC Main position and Generator and / or shore power are hooked up. DC voltage on all of my batteries (Engine Start Bat, House Bat, and Generator Batteries are all at 13.8 or 14.0 Volts when an AC source and Bypass SW in the AC Main position.

As I said before the inverter Bat and inverter terminals are reading within a hundredth of a volt of each other - so I don't suspect the battery or connections to the Inverter Input. I do have to go back and check the Inverter input DC voltage because of what gsholz stated about digital multi meters.

Today the Inverter control panel switch was in the off position for 4 hours and when I turned it back on I got a few spurious blinking lights on the inverter but no display there or on the remote inverter station at lower helm.

Not really sure where to go next but I am willing to keep trying things while waiting for a Marine electrician to call me back.

Thanks everyone,
Bob

 

[O C Diver]

Bob,
How about a picture of the main AC breaker panel. Would like to confirm that there are breakers for both shore power and the generator at the panel.

Next are all outlets fed through the inverter, or are some only accessible with the generator or shore power? Is there a separate panel for inverter circuits or are the inverter circuits marked on the main AC panel?

From what I've read, the inverter bank is holding its charge. Is that bank charged with the battery charger built into the inverter (battery charger is working) or is there another source to keep that battery charged?

Do you know if the inverter automatically switches from inverting to battery charger when shore power or the generator are sensed?

Ted

 

[kernr]

O C Diver - Ted you have asked some could questions.

I have attached a picture of the electric panel. When the inverter was operating if I turned on the switches below the inverter switch (with the exception of battery charger) - Cook Top, Washer/Dryer, and Water Maker no light would come on and I assumed that meant the power draw was too much for the inverter to handle and we needed either the generator or SP. Also the items in middle column - A/C (3), Fuel Polisher, and Water Heater I never tried to turn on while just the inverter was running but I suspect they too might be too much load. On the left side of the AC panel are two SP breakers for the forward and aft connection and at the bottom is the Generator. In this photo she was connected to SP from aft.

Your next question I am not sure I know the correct answer to about battery chargers. This Xantrex inverter is an inverter/charger. In addition there is a separate battery charger. However I do not know how the separate battery charger and the inverter charger interact with each other. More to learn!!

Also I don't know the answer to you last question. Because of what the marine electricians told me I have been switching the Inverter Bypass switch to AC Main whenever the Generator or SP are connected.

Bob

 

[O C Diver]

Do you have the manual for the inverter?

In addition to fuses for the 12 VDC input (which aren't part of the inverter), there should be an output circuit breaker in the event of an overload. This breaker is often a push to reset button located on the same side of the unit as the 12 VDC power input cables or 120 VAC output cables. Locate the breaker and try to reset it. If you don't find it, check the manual for its location. If the breaker is tripped, the unit may not switch to inverting as it doesn't see a load.

Ted

 

[kernr]

Ted - Yep, I have a thick manual for the inverter.

I did not know there was a breaker on the inverter for the AC output. As the inverter picture I posted shows the DC side to the right and the AC side to the left and quite a reach around the AC units. That is okay though - I am an ex submariner and very used to crowded equipment spaces and hard to reach equipment. This breaker is just around the corner and I will give it a push.

Bob

 

[sunchaser]

Kernr
On older inverter systems switches and operation can be devious as different electricians, owners and time have come and gone. Have you queried the previous owner as to your questions? Also, did the inverter work OK initially and now has a hiccup or just a puzzle since day one?

 

[twistedtree]

At this point I think you have verified DC power at the inverter terminals, yet both the local and remote displays go blank when you try to turn on the inverter. Is that correct?

At this point I can think of two more things to try.

1) Try turning on the inverter while you have your meter on the inverter DC terminals, and while watching the meter. Earlier someone mentioned how voltage readings can look fine until you actually apply a load. See if the input holds at 12V while the inverter is trying to power up. That should tell you if you have solid DC input.

2) turn off the rotary DC switch for the inverter, leave it off for maybe a full minute. Verify that the DC voltage at the inverter goes to zero when the switch is off. Turn the DC switch back on and try to start the inverter.

3) OK, make that three things. Try unplugging the cable for the remote at the inverter. Cycle DC power, then try to get it running. Maybe the remote has gone bad.

If none of this helps then I think you just have a dead inverter. They do go bad, and yours is pretty old.

 

[kernr]

Sunday Status

Okay -

Well I am now as confused as the next guy. I walked on the boat this morning and the yellow Inverting light was on and the display readout returned and you could change settings on the remote. it is almost like PFM and I didn't want to touch anything on the inverter. i did find the reset button on the AC output side of the box but did not press it due to thinking my inverter returned. Not quite sure what to think at this point. Maybe I should just enjoy the moment.

Any thoughts? Attached are the schematics that came with boat - both AC & DC

Bob

PS I do not know what the box below the inverter is and difficult to see through plexi-glass. I certainly have more questions than answers but I am learning.

 

[STB]

Bob,

I just caught up with this thread....but my bet is that your batteries were below inverter threshhold. I'd recommend checking water and keeping an eye on them to understand charging.

 

[kernr]

You could be correct on the batteries. it seems that they get from 12.8 VDC to 12.2 to 12.3 VDC in about two days. i recently asked the owner what the battery age was and he claimed not to know and no receipts. So my guess it the three 8Ds that are house / inverter batteries may be near end of life. I looked for a date punch on the batteries and there was nothing on the top. i might have to give them a full charge and see how fast each of them drop off in voltage. The inverter came on the day after running engines and generator for about 1 1/2 hours yesterday afternoon. Can I look up the inverter threshold on one of the inverter menus because it must be set - correct? i'll check it out - I wouldn't be surprised if it was set at 12.3 VDC.

I really appreciate everyone helping me out in these discussions - it really helps me learn the boat and there is a lot of experience on the forum. I will keep updating this thread until I feel we know root cause (5 whys)

Thanks,
Bob

 

[tiltrider1]

That inverter is completely programmable. The menu has 8 or 9 items. Then if you push two buttons at the same time you get a secret menu. This menu allows you to program the drop out values.

I haven’t studied your schematics yet but I am thinking that you weren’t given full details on how the inverter needs to be used.

 

[O C Diver]

Okay -

Well I am now as confused as the next guy. I walked on the boat this morning and the yellow Inverting light was on and the display readout returned and you could change settings on the remote. it is almost like PFM and I didn't want to touch anything on the inverter. i did find the reset button on the AC output side of the box but did not press it due to thinking my inverter returned. Not quite sure what to think at this point. Maybe I should just enjoy the moment.

Any thoughts? Attached are the schematics that came with boat - both AC & DC

Bob

PS I do not know what the box below the inverter is and difficult to see through plexi-glass. I certainly have more questions than answers but I am learning.

You owe me a beer.

I sent your inverter a telepathic reboot code because you seem a decent person and were trying real hard.

I can only do that once, so study and understand the manual and associated parts of your system.

Ted