How to tell when I'm full of *it!

Jul 7, 2004
8,402
Hunter 30T Cheney, KS
I'm wrapping up the installation of my SCAD Solo holding tank monitoring system. It's time to calibrate it. The instructions have a simple procedure to set the firmware's High and Low calibrations. One is done with the tank empty (easy). One is done with the tank full (not so easy). I had planned to flush 18 gallons of water down the toilet to be sure it was full and calibrate since there is no other way to know when it's full. The folks at SCAD say the calibration will be off since water doesn't have the "salinity" (his word) of waste. I still don't understand how the system works, but I'd like to figure out how to get closer to the "dialectic constant" of the fluid I am putting into the tank.
It's a Catch 22. I bought the monitor to be able to know when it's full, but I can't know it's full until it is. Any thoughts on how I might top my aluminum tank off accurately with something close to the real thing? FYI, we only use it for number 1 unless it's a real emergency.

For more than you ever wanted to know, here is some information on the types of technologies used to measure. SCAD uses the Capacitance design.
 
Jan 18, 2016
782
Catalina 387 Dana Point
Add salt to the 18 gallons of water you flush down it? Use gatorade? Invite a local fraternity over for a kegger - it'd get filled up pretty quick.

(I assume a boat in Wichita is not floating in salt water)
 
Jul 7, 2004
8,402
Hunter 30T Cheney, KS
Add salt to the 18 gallons of water you flush down it? Use gatorade? Invite a local fraternity over for a kegger - it'd get filled up pretty quick.

(I assume a boat in Wichita is not floating in salt water)
Funny! I had the same ideas but I wasn't sure. No salt water here, just runoff from nearby farms. We're a watershed reservoir.
 
Jul 29, 2004
406
Hunter 340 Lake Lanier, GA
Use a measured bucket to fill via the pumpout fitting to 95% of its rated capacity. Call that full so you have a little margin.
 
Jul 29, 2004
406
Hunter 340 Lake Lanier, GA
You do know what Peggy says about aluminum holding tanks?
Also on the suggestion above if you're not sure if the tank is really empty, you might want to leave a bigger margin
 
Jul 7, 2004
8,402
Hunter 30T Cheney, KS
I know. I thought long and hard about replacing it while it was exposed, but it looks to be in great shape. I had to go with the internal sensor because it was metal and not plastic. Empty isn't my problem. I want to know when it's getting full. e.g. In prep for last Labor Day weekend I went ahead and pumped it out just in case. Now I have an indicator for E, 1/4, 1/2 and full provided I can calibrate it correctly.
 

JRacer

.
Aug 9, 2011
1,331
Beneteau 310 Cheney KS (Wichita)
Leave it out back of the Afterdeck for the Super Bowl Party and put out of order signs on the heads in the building? :biggrin:
 

Johnb

.
Jan 22, 2008
1,419
Hunter 37-cutter Richmond CA
To get up to the salinity of sea water you would need 35 grams (1.25 oz) per liter of water (66 liters=17.4 gallons). You can easily dilute to half of that to approximate urine and flushing water.
 
Dec 2, 1997
8,708
- - LIttle Rock
I'm wrapping up the installation of my SCAD Solo holding tank monitoring system. It's time to calibrate it... I still don't understand how the system works,
With the kind of help you're getting from SCAD, I wouldn't be able to figure out how the systems works either!
The SCAD systems are actually just their private label brand name for the Profile system made by Ferriello Sales. Profile Tank Monitors Give Dennis Ferriello a call...he'll get you sorted out. 435.656.0042
 
Oct 2, 2008
3,807
Pearson/ 530 Strafford, NH
With our plastic I set a light on the top and I could see the level of materials inside. With it 3/4 full I set my tank gauge to full so I knew when to pump out. Never a problem.

All U Get
 

Gunni

.
Mar 16, 2010
5,937
Beneteau 411 Oceanis Annapolis
The folks at SCAD say the calibration will be off since water doesn't have the "salinity" (his word) of waste.
That is news to me. I purchased mine direct from Dennis Ferriello, installed and wired it ...2 years ago and never calibrated it. Have not used it. Would need to roost on the fuel dock to get the job done. But my plan was just like you, fill the tank freshwater and then calibrate. Report out when you get this sorted. thanks
 
Jul 7, 2004
8,402
Hunter 30T Cheney, KS
Quick update on my tank monitor system. Might give someone an idea to do it the same or better. I installed the indicator panel high up on the head wall above the stool. I used a piece of scrap HDPE to offset the panel to avoid a huge cutout for the circuit board. I just had to made a hole large enough for a few wires to pass thru. The block is attached using sealer.
The subpanel that powers the tank sensor and indicator is in the port laz. Also rewired a 12vdc cockpit outlet that was hotwired to the battery over to the subpanel.
I just need to get her in the water now and calibrate the Full setting.