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toskeysam · 07-18-2014, 07:21 AM

Fuses fuses fuses..... while rooting around in the power box under the couch. I have replacement fuses for all of the blade fuses in the RV, or so I thought. I saw the two bolt-down fuses in the box and figured it would not hurt to have replacements for those as well. There does not appear to be consistant information on these guys. The fuses are 200 amp fuses, one of the part numbers is for a 125 amp fuse, the wiring diagram calls out a 125 amp fuse in both locations. Anyone else see this as well? Fuses are cheap, but if they stepped it up to avoid spurious blown fuses, it would be nice to update documents (and labels) also. Did I miss something?

lewster · 07-18-2014, 09:10 AM

If you are talking about the barrel shaped fuses in the bolt-down metal holders, they are called class 'T' fuses and are generally used for inverter installations. Some OEMs use a flat style 'ANL fuse, but the class T fuse is instantaneous and will handle a surge of 10KA.

These are not easy to find, but I do stock them in sizes ranging from 120A thru 400A.

Drop me a PM if you can't find them locally.

toskeysam · 07-24-2014, 04:20 PM

Interesting things happening with new battery monitor. I did the reset as directed by Magnum. Everything zeroed out....then I watched as my amphrs I/O kept growing in the positive direction. That was with the shore power disconnected, solar showing ZERO input, and the refrigerator running!!!! WTF!!!!!! I give up!!!!!!!!!!!!

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lewster · 07-24-2014, 07:57 PM

Quote:

Originally Posted by toskeysam

Interesting things happening with new battery monitor. I did the reset as directed by Magnum. Everything zeroed out....then I watched as my amphrs I/O kept growing in the positive direction. That was with the shore power disconnected, solar showing ZERO input, and the refrigerator running!!!! WTF!!!!!! I give up!!!!!!!!!!!!

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Was it in "think'n" mode?

toskeysam · 07-24-2014, 08:04 PM

Lewster...it has never made it out of Think'N mode. I guess I should give it time to "reconsider" now that I did successfully get a reset. One good thing I can say.....those brand new Lifeline batteries HOLD A CHARGE very well. Granted, that was not part of this thread....I just had to tell someone

lewster · 07-24-2014, 11:29 PM

Quote:

Originally Posted by toskeysam

Lewster...it has never made it out of Think'N mode. I guess I should give it time to "reconsider" now that I did successfully get a reset. One good thing I can say.....those brand new Lifeline batteries HOLD A CHARGE very well. Granted, that was not part of this thread....I just had to tell someone

Thanks! Your secret's safe with me!

As you (and most folks around here) know, I'm a big fan of Lifeline AGM batteries. A couple of years ago, I was moving my storage area and came across a couple of whits Lifeline battery boxes. I regularly use the empties for storage, as they are very durable, double wall cardboard....great for very heavy items.

So I move a bunch of stuff and see these 2 boxes where they shouldn't be and I am wondering just what I stored in them? I go to move one and it's really heavy....sort of what a battery weighs. But of course, it couldn't be a battery, as it would have been in storage for over 8 months!

On opening the box, I found a brandy new Lifeline GPL-6CT 300 amp/hour golf cart battery, and also found it's twin in the next box. EUREKA, I have found treasure!!!!! Over $800 worth of batteries just sitting there forgotten. But of course, they won't be much good as they have been sitting on the shelf for over 8 months....they must surely be discharged by now!

After removing them from the boxes and adding a series connection for 12VDC, I test the batteries and guess what? They read 12.8 VDC on my Fluke meter.....100% charged!!

They now reside in my service van, getting their full charge from the 500 watts of GS-100 panels that I have on my roof.

They surely DO hold their charge well!!!!

73shark · 07-25-2014, 12:14 PM

Sounds like a positive example of you get what you pay for.

lewster · 07-25-2014, 01:37 PM

Glad the comment had no negative connotations. :-))

Lew Farber
RVIA/RVDA Nationally Certified Master Tech
Master Tech Energy Systems, Inc.
AM Solar Certified Installation Center
Lifeline Batteries**Magnum Inverters
541-490-6357

toskeysam · 07-29-2014, 07:14 AM

Hmmmm....Still no joy with the battery monitor. Crawling around the back of the van I spotted what may also be a problem. Even if the monitor stopped "Thinkn" it would not see any the loads across the shunt....except through the inverter. It looks like all the 12v loads are parallel to the shunt...instead of THROUGH the shunt as shown in the hookup instructions. The only loads the shunt would see are those coming through the inverter. I am no electrical engineer (actually mechanical engr) but it sure looks like a screw up to me. (on the part of my installer-not Airstream) I don't know.....so I am going to be "Thinkn" about this myself for a bit. All systems functioning, except monitor, so it can wait until I get back home in Oct.

lewster · 07-29-2014, 08:36 AM

Definitely an 'AH HA!' moment. There are several grounding bus bars and negative frame mounts in the AI, which makes it difficult to get all of the negative loads running thru the shunt. Try using a binding post on the output side of the shunt (non battery side) to attach cables to any bus bars or other grounds that you can find. You can also slide the batteries out of the box and 'insert' the shunt between the battery negative and the original negative cables, add the inverter negative and you should be ready to go. Hopefully that will solve your problem.

PS: Was this the first BMK that the installer did?

toskeysam · 07-29-2014, 08:56 AM

Lewster...thanks for the suggestions. The battery box looks most promising to me. Seems it would be a simpler hookup. (For some reason, the Magnum instructions say not to put the shunt in the battery box, but worth a call to them to find out why, or a re-read on the manual/instructions)
The installer seems to know his stuff and has been spot-on with other questions and instructions. I will give him the benefit of a doubt this time, and lump it up to the spring rush.....2 techs working a 10 bay RV shop. We ARE going to discuss it when I get back.

toskeysam · 07-29-2014, 09:40 AM

Lewster....here is what Magnum has to say about the shunt.

Info: Shunts should be mounted in an area where freely circulating

air is available. For continuous operation, it is recommended that

shunts are not used at more than 2/3 of their rated current. If this

is not possible, adequate forced ventilation should be provided to

keep the shunt operating temperature below 60°C.
Guess its going to be a little more complicated afterall.

lewster · 07-29-2014, 02:03 PM

Since all negative loads start at the battery negative terminal, the easiest thing to do is place the shunt between those cable(s) and the battery negative. Add another cable of proper size between the shunt and battery negative and then add the inverter negative to the load side.

That should cover all the bases.

Lew Farber
RVIA/RVDA Nationally Certified Master Tech
Master Tech Energy Systems, Inc.
AM Solar Certified Installation Center
Lifeline Batteries**Magnum Inverters
541-490-6357

toskeysam · 07-30-2014, 10:34 AM

Lew, Many thanks for your insight and advice. I hope to get this mess straightened out. There are going to be 2 stages to this fix. First to get the tie-in points correct to see all of the loads. Second to verify that the sensor module wasn't fried by a bad installation step. Magnum indicated the sensor may be faulty considering the strange readings I am still getting after the hard reset. ( 128. amps DC and the AMPHR I/O just keeps rising...even under a load with no power into batteries) It still says "Thinkn", but I think it really means to say "I GIVE UP"....just not coded into the display that way. Fortunately, none of this is a show/trip stopper so it can wait until I am home.

lewster · 07-30-2014, 09:26 PM

Keep me posted!

pebbrb05 · 07-03-2015, 06:28 PM

Need help. Returned from trip and found 110 power to Interstate had tripped and batteries were dead. Reset 110 GFI and Magnum monitor registered fault no comm. Checked Magnum manual for fix. Removed monitor, unplugged telephone wire for 5 seconds, and replugged. Got brief flash of green but returned to red no comm fault. Repeated several times with same results. What's my next step.

NOLA_russ · 07-03-2015, 08:05 PM

I just encountered the same fault after killing my house batteries. I started the engine and for some reason that cleared it. Good luck.

lewster · 07-03-2015, 08:55 PM

Quote:

Originally Posted by pebbrb05

Need help. Returned from trip and found 110 power to Interstate had tripped and batteries were dead. Reset 110 GFI and Magnum monitor registered fault no comm. Checked Magnum manual for fix. Removed monitor, unplugged telephone wire for 5 seconds, and replugged. Got brief flash of green but returned to red no comm fault. Repeated several times with same results. What's my next step.

Try a 'hard re-set'. Remove the positive power feed to the Magnum (since you don't have a disconnect switch, which I always include in my installations) by removing the inverter fuse from the line. Also remove the telephone style cable at the inverter that leads to the remote monitor and be sure that there is no 120VDC going into the unit. Wait 15 minutes and attach everything in reverse.

If that doesn't re-set your problem, you might have a bad board internally and need to contact a factory authorized Magnum service center for service.

pebbrb05 · 07-04-2015, 05:52 AM

NOLA russ and lewster - Thanks for your prompt help. Tried NOLA russ suggestion first and it worked. All is well. Will keep lewster's direction on file for future trouble shooting.