Alde Control Panel dark, does not work, Alde blows 3.15 Amp fuses, why run a new ground wire?

vhollow

I have owned a Tab 400 for a year now, put 13,000 miles on it, and used it off and on for about two months of total travel.  During that time, I too experienced the control panel ceasing to work, and had to replace the glass fuses on top of the Alde unit—primarily the one on the negative 12V side—four times, until I fixed the problem.

Before elaborating on the fix, I would like to say thank you to Photomom, for this:

Reliable source for Alde fuses

Photomom Posts: 2,001Member
July 2016 in Heating/Plumbing & Winterizing

I used her source and received my 10 hard-to-find 3.15A fuses promptly and inexpensively.

Second, I want to point out the thread started by TerryV6:
Running a ground from the Alde to the battery
discussion by TerryV6 · September 2017 · Battery/Electrical & Solar 

This thread is very useful, and contains advice from Alde Service, and, in the responses, from NuCamp Service too.  Missing though, is the explanation for why the the 3.15A fuses frequently blow.  The reason is that there is too much resistance in the negative wire from the battery to the ground bus bar (strip containing multiple negative 12 V wires) and from the bus bar to the converter (where breakers and fuses are located).  There is too much resistance, because the wire diameter is too small for the length involved from bus bar to battery.  So, when the converter is plugged into 120 AC (shore power), and sends a pulse of 12V DC to the battery to test positive resistance and determine the voltage to supply for charging the battery, the excess, instead of travelling down the negative wire to the battery, seeks a path of lower resistance, and finds one in the negative wires attached to other devices, specifically, in this case, the Alde, and blows the negative-side fuse, although it can also blow the positive side if the surge is big enough.  The systemic solution is to change the negative wire from the battery to the bus bar, and from there to the converter.  I recommend using a 6 AWG thin strand wire, which is the biggest that is practical, and which can be purchased by the foot at Home Depot.  That way, 12 V voltage surges, or pulses, will not look for low resistance in any devices, like the CoolCat, or stereo, in addition to the Alde.  Moreover, if you move the ground wire from the Alde off the negative bus and directly to the battery (I went with 12 AWG, just to have as little resistance as possible), back surges will not have a path to the Alde ground wire, as has been suggested by the service people.  Now, I am not an electrical engineer, just an amateur, and a DIY guy, but I have had no further problems since making these changes. 

I will close by relating an analogous experience with the Tab 400 . When I purchased it last Nov. 2, 2017, it came with a dead battery and a blown fuse protecting the battery.  I replaced the fuse and charged the battery with a trickle charger, then plugged the trailer into 120 AC.  At that point, the fan in the breaker box/ converter came on and stayed on.  I contacted NuCamp warranty, and they sent me 10’ of 8 AWG wire, plus a 40 amp breaker, to replace the existing 10’ of 10 AWG wire with a 30 amp fuse.  They did not include an explanation, but I surmise it is this: The resistance in the 10 AWG/30 Amp fuse arrangement was too high.  Sometimes this resulted in blowing the fuse.  When it didn’t blow the fuse, the converter sensed high resistance on the positive side (which generates heat) and turned on the cooling fan, even when the battery was already fully charged and no high amps were in use.  By switching to a larger copper wire diameter and bigger breaker, resistance on the positive line from battery to converter was lowered and the problem was solved.  Hmmm, what does this say about possible resistance problems with the 10’ of 10 AWG wire on the negative side of the system?  Has NuCamp addressed this in more recent trailers?  Might it be an issue for other models too?  So, in my case, I switched to a larger diameter ground wire, I believe for the same reasons that NuCamp sent me a larger diameter positive battery wire from battery to converter. 

ChanW

Great explanation.

I remembered the mention about the ground deficiency causing the Alde fuse problem, but couldn't remember where the info was!

Thank you.

falcon1970

I do hope nuCamp has sorted this out and are putting the proper wire gauge and fuses in the current models.

ChrisK

Thanks for this info. I read the Alde install manual and they say 16awg from the battery to the unit if the run is less than 65ft. I have a thick wire running to the inverter (for while on solar, not the converter) in my electrical compartment. Might just have to run the ground from the Alde to that. Run would be about 6 feet.

jgram2

Welcome to the forum and thanks for the information you have provided! 

vhollow

Well, I have to somewhat sheepishly amend my long-winded explanation, with another long-winded explanation. Changing the wire diameter from the DC converter to the negative side of the battery may or may not be necessary. I did that, and moved the negative wire from the Alde 3010 off the negative bus bar and directly on to the battery negative terminal.  This did indeed solve the issue of back surge when the trailer was plugged in or unplugged from 120 AC. I should clarify as well, that I always had the Alde turned off for all location moves or power changes, so that was never the issue.  However, I continued to blow the negative fuse on the Alde 12V ground wire when I would unplug from the towing vehicle (TV). Sometimes, the fuse would form a little globule on it, and still work connected to the TV, but not when unplugged from the TV.  Why?  The explanation is that the negative side of the battery itself is insufficient to prevent back surge.  My Tab 400, built in Aug. 2017, has a floating ground system.  That means that the 12V battery is not itself grounded to something else.  When it is fully charged, there is not much space in it to draw negative electrons (the resistance is too high).  It is like trying to pour water down a pipe into a full cup.  My TV is a truck, with its battery strapped to a truck frame, which provides a large reservoir of low resistance ground.  When the trailer is plugged into the TV with the 7 pin connector, it shares that ground.  The Alde control panel, the stereo system and the carbon monoxide alarm all use a little power even when "off," and the refrigerator uses more when on while I travel.  The discharged electrons flow from these sources to the truck ground, because it is "better" than the Alde floating set up. Unplug the TV and back surge happens as the systemic current looks for a new ground, goes up the negative wire of the Alde, even connected to the negative battery terminal, and burns the fuse.  The solution is to ground the trailer battery to the trailer chassis, and connect the Alde ground wire to the same chassis ground terminal.  That way, any negative electrons not accepted by the fully charged battery flow into the chassis, instead of traveling up the Alde ground wire to the fuse. It only took me ten fuses to arrive at this point! Phew! I think I read that the Alde 3020 does not have a ground wire fuse, so maybe that upgrade provided a different solution.  Also, my Tab 400 chassis is constructed of pre-painted C channel and bracing, all riveted together. I did not test to see if it formed a unified ground, although, in retrospect, I should have, since I doubted it would. An electrical engineer could calculate if one side piece of chassis was enough additional ground, not welded to the rest. My response, maybe excessively cautious and DIY, was to bond the chassis pieces myself into a unified ground.

Michigan_Mike

Good information and it makes sense.  And unfortunately the weak link to all of this is the fuse at the Alde.  The circuit voltage imbalance is the culprit and I think that anyone who has owned a T@B equipped with the Alde sysytem has at one time or another experienced this phonomonon.  

I deal with with it in a simpler method by leaving the Alde off,  hooking the trailer up to shore power or the tow vehicle, etc. and having everything in place before turning the Alde system on.   If you don’t do this and are running the Alde prior to plugging the trailer in to shore power you risk blowing a fuse.  On the flip side before breaking down camp we turn the system off first, then unhook from shore power to eliminate the same scenario and also as a means of not blowing a fuse at the next campsite.  

I’ve always made it a practice to ensure that the campground pedestal circuit breaker is in the off position when hooking up my trailer to eliminate the potential for any current flow to the trailer.  Once things are fully connected I then flip the breaker on and when breaking down camp this is done in reverse.  Bottom line here, the Alde is always our focal point, we pay attention to it and make sure it is turned off before unhooking from shore power and procedurally make sure it is shut down properly when breaking camp to eliminate blowing the fuse at the next set up if someone were to forget turning it off.  To date this process has performed flawlessly and I’ve had no fusing issues.  

BrianZ

We do the same as @Michigan_Mike and have never used any of our many spare Alde fuses in the 1-1/2 yrs we've had our T@B.
However, I can see how the wire gauges might be inadequate in some situations.  
As far as explaining current flow in those situations in terms of "electron flow", it can get confusing, because conventional current flow in DC circuits is normally from positive to negative, while electron flow is normally negative to positive.

vhollow

I follow the same routine as Mike, above, which makes good sense! In my case, it wasn’t enough. That might be a problem only for a subset of early 400s pulled by trucks. And Brian is correct about the electron confusion. The heart of the issue is having a good enough ground system to avoid back surge blowing the 3.15 amp fuse on the Alde 3010 ground wire.

vhollow

I should add that plugging into shore power, or unplugging from it shouldn’t affect the Alde control panel circuit, which gets its 12 V DC either from the converter, the battery, or the solar, assuming the Alde is off for all changes, but it did for me, as did unplugging from the TV, until I grounded to the chassis.

Ratkity

I'm not sure why, but some people have issues with the fusing. I never had one, but had those fuses on hand. Used the same procedure as M_Mich, but others using it have had issues. Gremlins, I tell you!!!! Gremlins!!! *regains control* 

While the battery is supposed to be a big buffer and have always said as such, alas, I've been corrected by my motorcycle mechanic friend who said that's not always the case and he doesn't know why. *GREMLINS!!*

I wish all who are having trouble that the fix suggested works. The back surge issue made sense because my sister's TV went out the 2nd day of operation. She had the old analog Alde panel (2015), yet never had another problem until she sold it. Why??? Only the gremlins know.

Best to all who are having this issue.