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  #1  
Old 04-27-2013, 08:23 PM
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Flyguytki Flyguytki is offline
 
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Default Capacitive plate issue

During the tank calibration over the course of yesterday and today I think we have concluded that in the right side tank, somewhere the plates are grounded. I am not sure how or when this happened but I have pictures of the volt meter showing that when the tanks were closed everything was working. I'm pretty much at a loss of what to do. Anyone ever encounter this or have an idea of where to troubleshoot or start a fix? Wings are painted and bolted to the fuse.

THanks in advance
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  #2  
Old 04-27-2013, 08:30 PM
rapid_ascent rapid_ascent is offline
 
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Have you confirmed that you have a short between the plates and the skin or are you just not getting the reading you expect?
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  #3  
Old 04-27-2013, 08:36 PM
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Tragically yes it is a short :-(
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  #4  
Old 04-27-2013, 09:42 PM
E. D. Eliot E. D. Eliot is offline
 
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Default Maybe

It could be in your wiring from the tank to the gauge. What reading do you get on the gauge with the tank wires disconnected? Just hoping that this is the answer.
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  #5  
Old 04-27-2013, 09:58 PM
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Flyguytki Flyguytki is offline
 
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Quote:
Originally Posted by E. D. Eliot View Post
It could be in your wiring from the tank to the gauge. What reading do you get on the gauge with the tank wires disconnected? Just hoping that this is the answer.
It shows right at .8 volts or so. The problem is when you touch the inside pin of the BNC on the tank, and the rib of the tank you have continuity.
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  #6  
Old 04-28-2013, 05:43 AM
jarvis jarvis is offline
 
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Quote:
Originally Posted by Flyguytki View Post
It shows right at .8 volts or so. ...you have continuity.
You are reading voltage ---but describing a continuity check. I assume this is inadvertent on your part--or I'm misreading what you're saying. Anyway, be sure that your are indeed reading resistance and not a "ghost voltage".

Secondly, look down the barrel of the BNC with a really good light and be sure a big aluminum chip--or some other conductive material--isn't shorting the pin to the barrel. Once saw a piece of aluminum foil do this. Very hard to see if it's pressed flat in the bottom.

Sincerely hope it's something simple--outside the tank.
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  #7  
Old 04-28-2013, 12:50 PM
flyer174 flyer174 is offline
 
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Also make sure you used the correct spacer washers between the rib and capacatence plate,seems like there was some black ones that came with the kit and vans sent some white ones as a replacement,our builder number is 70815.some conducted electricty was the reason for the change.
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  #8  
Old 04-28-2013, 06:34 PM
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Flyguytki Flyguytki is offline
 
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Problem Solved:

The Bad: The Plates or Wire or Connector are touching the vent line somewhere inside the tank.

The Good: The Anodized fittings are non conductive, The Vent line is housed in plastic bushings throughout the ribs, Therefore the only place which is grounding to the tank itself is the small tab that holds the vent line at the filler cap. All that was needed was to remove the tab that supports the vent line and everything is good to go. The tank was calibrated to 21 gallons with the exact same .4 Volt variation on the skyview from empty to full.

Thanks for all the help,
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