Accu-Gage Tank Level System- BLACK tank not working.

[lngfish]

Hello,

This is made by Larson Electronics.  My pile of info has not much on it.  All the other tanks work OK. These being LP, GRAY, BATTERY, FRESH BLACK has never worked since I have had it and I never looked into why it has in 12 or so years.
Yesterday I did look.

At BLACK tank I see two wires going into tank area and allot of insulation. From looking at FRESH tank looks like 2 pieces of aluminum foil are taped to outside of tank.  I assume BLACK tank same set up as FRESH but totally covered with insulation. Looks like some sort of capacitance set up.

I found (2) Orange wires in sta-con going to one wire.
This sta-con was crusty so I replaced it.
I filled tank to 98 % visual, and turned SPAN screw FULLY CW and FULLY CCW, no change; reads empty with empty RED LED on.

I have no idea where to check for voltages or grounds as I don't know how this works or capacitance readings if I knew how to take them with a DVOM.

The FRESH thanks has (2) orange wires going to ONE wire as does the BLACK.  So I assume ORANGE goes TANK TO TANK like it is 12VDC or something. [size=78%]NOT SURE.[/size]

Anybody know anything about this system?

Thanks,
Steve

[Rickf1985]

If I were to guess I would say you are right about the orange wire being the supply. I woulds say however that the system probably works on resistance and not capacitance. With a volt meter and the ground wire of the voltmeter on a known good ground check the voltage of the orange wire at both the fresh tank and the black tank and see if the reading is the same. Then check the other wire coming off and see what the readings are on that. I am going to guess that the fresh tank will be less than 12 volts. The black tank is probably zero. Now turn all power off and disconnect one wire or the other on the fresh tank and check the resistance on the Ohms scale across the wires on the tank sensor. you should get a reading, the black tank is probably showing open circuit. I will bet that buried under the insulation the foil has broken or corroded apart. This is all guess work but the tests are free and will not hurt anything and should tell you something.

[DaveVA78Chieftain]

I suspect you use the moda sensors.  See if the moda troubleshooting procedures on this web page help you isolate the issue.

[lngfish]

I will,

Thanks to you both. Going to check link and do that volt check if needed.

Good procedure
BRB,
Steve

[lngfish]

Guys,

Mine doesn't look like any of those.  Mine is prior to 1996, a 1987.  I'm going to do Rick's check and see what I get.

Thanks,
BRB

Steve

[DaveVA78Chieftain]

There are 2 types of tank monitors that I know of
1. The older 5 wire button style (ground, 1/4, 1/2, 3/4, full) used on my rig.  Holes are drilled into the side of the tank that the buttons are glued into.  Ground is bottom button. fLights are lit when the water level reaches the next level button (continuity between ground button and level sensor button).
2. The 2 wire moda sensor that has sensor at each of a foil strip that is glued to the outside of the tank.  No holes are drilled into the tank.  I believe a change in water level changes the capacitance of the circuit which is read by the monitoring unit.

[ClydesdaleKevin]

My old 77 Itasca had a third style system, that I don't know the name of.  A rod dropped down into the tank from the top, with 5 wires coming out of it.  It was actually a plastic tube with varying length metal rods attached to it, completing the circuit depending on the level of the tanks.  Ground, 1/4, 1/2, 3/4, Full.

Kev

[lngfish]

OK Guys,

Mine has go be MODA.  2 huge patches of foil taped to outside of FRESH tank. Assume BLACK same.

My FRESH was working but now it isn't. It stopped working after I snipped one of its wires at tank when I had the PB strapped down at panel where you PUSH to READ, (depressed this button with a jig)  . Ooops.

I was thinking best to have button pushed to take voltage. 
I was trying to get some info VOLTAGES off the working tank, FRESH.
Now BLACK and FRESH read EMPTY.

Going backwards on this fix. lol

Been here before.

[lngfish]

HI,

From reading the systems available on Tankedge site the I-Series looks pretty good.  For about $200 I could update what I have with a crap load of work.

I like you can set in alarms HI/LO
Anybody ever use this I-series with Capacitance sensors?

I wrote them to see if they can assist with what I have now just in case they know something to get me going since most of what I have works.

Good link, THANKS!
Steve

[lngfish]

Forgot to mention,

I read 12 VOLTs on Aluminum FOILS when PB not down and 7.5 VOLTS on one foil and 6.5V on other FOIL when PB DOWN.

Weird that any voltages on foils but I guess how it works as foils exposed to ambient and could get shorted to ground where FRESH tank is, moving things around I guess.

Strange system for sure.

[lngfish]

Hello,

https://tankedge.com/downloads/Moda_Sensor_Testing_Procedures.pdf

MODA Is 3-WIRE SYSTEM- (DC-Ground-Signal)

that PDF tells me that if mine has sensors, IT MUST, they are under the foil even though mine is old it must have sensors under foil, but all you see is foil.

Seems the MODA system outputs 10VDC (Regulated by Panel), not like mine but newer panels, on RED/BLACK wires to tank.

Then somehow, a BLUE wire feeds back to panel no HIGHER than 5 VDC. (Not my system again)

Putting hand across 2 tapes, makes BLUE voltage spike.

If my FRESH now reads LOW where it worked before I probably wiggled a sensor wire loose and broke it. Things are fragile. Perhaps soldered.

Something to look at. Thanks for great link again. Got to read that PDF today.

Steve

[lngfish]

Tank-edge fellow Mark called me yesterday, very helpful.

He told me these systems work on radio frequency.

The older systems like mine have one MODA signal generator on the control board at panel.

The newer systems have a MODA signal generator at each tank. 3-wire. BLACK RED BLUE.

On an older systems you push the button, the MODA generator on the board, like mine, generates a radio frequency and sends it down one of the wires to one of the foils. The other foil pick up the RF signal. Depending on strength other foil picks up signal indicates level. Older systems have shielded cables. If a wires is snipped you must re-connect the shields. I don't think I did for the FRESH.

He gave me enough information for me to TS and maybe what I have but I decided to upgrade to the new I-Series they sell.

I figure labor about the same to fix or replace and a good area to upgrade. BLACK never worked on mine.

The reason being their system monitor all tanks every so often and you can set in hi and low alarms.

Their systems also has switches for my water pump and HOW Heater, both switches with lights, like I have now.

Switches are $5 each. I'm thinking installed on panel when I get it. Hopefully.

Also, Mark advised, getting a Diode board upgrade option, $25. I think Diodes come in pigtail.  This allows me to somehow get by with less GOOD WIRES to the tanks.  I could STILL have one bad wire to BLACK tank still since I never got to fix it.  WITH new system you don't need shielded signal wires a HUGE PLUS. You can daisy chain 12V, and ground or ground each tank separately or do both.

Each tank has it's own MODA module not just one at Panel.  His panel will sit inside my panel's faceplate  after I cut out my panel front faceplate.  His system if current technology and you can set to monitor thanks every so many minutes.
15min I think.

The I-series monitors coach voltage also and can monitor alarm on it also. LOW

I hate looking in toilet to check level and would hate an overflow if a toilet water valve fill valve leaked.

I like have an alarm on all tanks too, HI and LO.

I will have PROPANE, VOLTAGE, (3) WATER TANKS.

Steve

[lngfish]

Typo:

His system "is" current technology, not "if"

[Rickf1985]

Seems like the right way to go, fixing shielded cable is always a crapshoot.
Now the big question, How much?

[lngfish]

It arrived:

Tech-Edge

326 Series I series Integirty Panel Tank Montoring Kit with 3 sensors, fuse assembly & instructions    $229

Water Pump Switch $5.00

Water Heater Switch $5.00

Diode Modification $25.00

Mark it the tech there. He is helpful on phone. I told him my Black tank never work so he suggested getting the Diode mod so I did. With diode Mod you can tie more than one tank with one power from board and can use less power wires from board. He was thinking I may need this option and I may need it as I can not see that the Black Tank was EVER wired at factory.

But I'm not 100% sure yet.

Yesterday I spent time looking over wires on current panel and got Fresh Tank Level Working, Bad solder at tank and some bad connectors. One of them the was problem. So now ok.

Directions look very good.

I need to look over wiring at Grey and Black Locally when it stops raining.

The switches new panel have LEDs and it looks like they are compatable with what I have.

System looks well thought out.

[lngfish]

Turns out the shields are not connected at tank end only at board end on old system. I tried a few combos.

[lngfish]

The 3 tank means 3 Liquid Tanks, ie Plastic tanks.

The system also has provisions for LPG Tank Level and Battery Voltage Level.

So 4 Tanks Plus Voltage Monitoring all with alarms.

[lngfish]

I found this article today, a good read I thought:

http://www.sanidumps.com/product-testing-tanksystemsmonitor.php

As far as my I-Series I have the Water Pump, and Water Heater SWITHES/LEDS so far switched over.

Quit a mess with 2 panels hanging at door. Got to go slow and go wire by wire however.

Just can't slam door on the mess.

Fresh Level next, inside, then when rain stop I'll get under and do Black and Grey Tanks.

I do like the way Brighter LEDs on new panel over sort of dim light bulbs on old panel.

I'm past the point of no return now.

[lngfish]

I'm pretty sure Black Tank never worked since I can not see where wires were ever run to panel. Weird.

[lngfish]

Powered up panel yesterday before really getting the water tanks done. I taped ends. I wanted to see how it looked. Sure looks nice and no smoke yet, a good sign.

Actually, I did it to make sure the Water Heater Switch and Water Pump Switches worked properly and they do and I wanted to see action on display, something happening. New LED's on both switches wicked bright.

I used the original LARGE U-mounting panel but knew the  new I-series insert (FACE) wasn't as wide as the older panel (FACE) and left a 2" or 2" hole or so,  so I took about 2-3 inches of Old Panel Face , on left, that has HR Symbol, to cover this hole to the left of the new panel face.

"This looks sort of like" the new I-series panel is OEM, in my mind anyway, and jogs new panel slightly to the right but not too much and eliminated me making a full panel insert in old panel face. Short-cut and looks more finished with less of a mod look.

This does not affect using the old PB Face, doubt I would, but it is a good spare for another functioning system, as it is ONLY face plate with HR symbol where there are no buttons or electronics behind this HR symbol.

[lngfish]

Update:

Finally got under to check wiring at Black and Grey tanks.

These 2 tanks wired slightly differently than Fresh Tank.

Fresh Tank uses BOTH Blue Cords.

Under RV the Black and Grey Tanks SHARE and Grey Cord.

So BLACK tank was factory wired.

It appears old systems ALL TANKS HAVE ORANGE wire on one Aluminum Foil and the other Foil Takes Back the Signal to the board for the respective tank.

Looks like the Orange side Foil Signal is perhaps constant signal on all tanks since it appears this wire is common to all of these tanks.

IE:I see (2) ORANGE at Fresh Tank, (2) at Black Tank and (1) at Grey Tank.

So Fresh Tank 1st in series and Grey is last, Black in middle.

Anyway old wiring pretty sad at Black Tank and Grey tank under RV.

Since each old signal wire had inner copper and a shield copper and aluminum foil over both it looks like each side of each cord has 2 good conductors both approximately 18g. Super fine copper hair wire.

So where new board goes and is now mounted, I just set aside (PULLED OUT) these BLUE and GREY CORDS and DUCK TAPED the to wall and numbered them.

Now I need to decide to put new sensors where old ones were or put in a new location.

hummmm

I'm thinking new location, less work.

[lngfish]

Darn Typo:

Grey and Black TANKS share the GREY CORD.

This Grey Cord has (2) insulated conductors, looks like what you would see running to an old lamp but lil FATTER , "FLAT"- bonded together easily ,  but each one is a (2) conductor shielded conductor.

[lngfish]

Too much rain here can't do much under RV so put Foils on Fresh Tank, did Empty and Full Calibration as per manual, fairly easy, and checked accuracy and set alarm, LOW, at 25%.

Read out is 0-100%.- back lit looks nice in blue.

I was able to run foil to very top and very bottom of tank, a plus.  FRESH TANK

Book says if u can't bring back 1/2".

This may sound a bit complicated but in the calibration mode, not the what you see mode you get a Empty and a Raw and a Full Number. THREE NMBERS

It gives you this based on I guess the amount of tape, etc, signal received back.

Anyway, my Empty number was 42, and my Full number was 160 and RAW varies.

RAW is level in tank.

So 120 difference between the two (160-40).

This is in calibration mode, not view mode.

Anyway, in this calibration mode I could see the 160 number drop slowly digit by digit as I drained it.

This pretty accurate to say the least.

Roughly a third of a gallon per digit in Cal Mode.

Anyway on the view mode, which is 0-100% is would be almost as accurate.

I set alarm at 25%.

I let tank run to 0%, while running pump.

The pump ran dry after a min or two after the 0% came up on panel.

Black and Grey Next.

Steve

[lngfish]

There are 2 Orange wires in the old level system of this 1987 Holiday Rambler, Alumilite 30 Footer, and might be same as others.

One if for the Propane tank and it is at the Level board on old system and it connect right up on new system.

Directions good for this. Easy to connect up . No calibration needed.

The other Orange wires are in the back of the RV.

There is one at the Fresh Tank, 2 at the Black Tank and One at the Grey Tank.

They run in the harness back there. I rang out the wires to make sense of them.

These are not used for the NEW SYSTEM Power or Bringing the signal back on the new I-series system I am installing.

Also, "they do not come all the way back" to the panel EITEHR but they can be used to bring back the Common (-) to the panel.

Each tank needs a (-)

This is how I did it on mine.

The Fresh Tanks has Physically 2 Blue Cables- 4 Conductors. You only need 2 and a (-) per TANK.

On mine there were 2 Conductors not used on the Fresh Tank. "One Cable"

*****This is one Blue Cable out of two Blue Cables******

One Blue Cable will be used- 2-Conductors for the FRESH TANK.

Each Blue Cable has an inner stranded fine copper wire and an outer stranded copper wire and on top  of these two is a shield.

The shield is not a conductor to be used, just a shield. It does not need to be connected for new system so just get it out of the way neatly. It comes off in a circular motion or scape it off with back of blade.

At what ever tank you have an extra cable, in my case Fresh Tank, you can use ONE Conductor of the Spare Cable to carry the (-) back to the panel.

And I did not want to Ground Locally as not a good connection in most cases underneath.

The Orange wires in the OLD system were common powers somehow. I never sketched it out but each tank had one Orange on one FOIL per tank but only one tank was fed this COMMON POWER and it was daisy chained around. Parallel.

Reverse this thinking and use the COMMON Orange again and use it to bring (-) back to Panel using the spare Conductor at Fresh Tank since it HAS  a spare cable going back to panel from it's location and also an Orange wire like other 2 tanks, (Black and Grey)

In my situation I used a Blue Butt Connector at Black Tank, fed the 2 Orange Wires in one side of Butt Connector, out other side of the Blue Butt Connector WITH (-) to Black Tank, and (-) to Grey Tank. Doing this puts these 3 tanks in parallel and common to Fresh Tank and you don't have to mess with wires or add any or even look into the looms.

Then at Fresh Tank connect it's Orange wire to a spare Blue Cable wire that in turn goes back to panel.

At Panel connect it to Common (-).

NOTE: On these cables to make sense of them to me I did like this in my mind.

I'd say: Examples ( Inner insulation is either Red or Clear) ( outer insulation is either Blue or Grey)

BLUE-RED-CENTER 
BLUE-RED-OUTER

Blue-CLEAR-CENTER
BLUE-CLEAR-OUTER

GREY-RED-CENTER
GREY-RED-OUTER

GREY=CLEAR-CENTER
GREY-CLEAR-OUTER

Top Line: Means Blue Cable, Red Inner insulation wire , as it could be Clear instead.
2nd Line: Means Blue Cable, Red inner wire but the conductor around the inner one.

The other 4 same thinking.

So on and so forth.
Steve

[lngfish]

Wired up Grey Tank and did calibration on it.  Extremely accurate and repeats on a dime.  Full and Empty Calibration.

Easiest method.

Wish my Grey Tank was bigger!

Not sure how big it is but is does not hold much water and fill up after a few showers.

Darn!