Garnet 709-RVC NLP Manual page 29

"see" the water will ensure proper level calculation and sender
operation.
2. The signal strength should be in the 50% range for best
performance. If the signal strength is in the 20% range it is
indicative of a high resistance in a connector, a bad ground,
or improper bonding of the sender to the tank (a possible air
gap on one or both sides of the sender).
3. With the console installed you can check the level on each
tank, if you get an indicated level of 10% to 20% and you
know this is too high, reposition the sensor board as follows:
In the case of a convex tank bottom, usually found on large flat
tanks, raising the sender is the best solution to accomplish a
zero reading when the tank is empty. This may result in having
to shorten the sender by an additional segment.
On sloped tanks, which are used to promote complete draining,
one alternative is to measure the end of the tank opposite from
the drain valve. It may be necessary to extend the wire harness
to be able to measure on the optimal side. On the drain valve
side, the best choice is to elevate the sender to avoid reading a
puddle at the drain valve.
4. The close proximity of metal to the sender can be misinterpreted
as water, since they have similar electrical characteristics. Any
metal such as steel, aluminum, copper, or brass can affect
the sender reading if it is closer than about 2" from the face
of the sender. If there are metal frame pieces, brackets,
straps, pipes, ducts, etc. close to the sender you may have
to move the sender away from them. Again, trial positioning
using tape is necessary until the problem disappears. Flexible
pieces of metal can be held away from the sender with rubber
wedged between the sender and the metal. If the metal is off
to the side of the sender, or just butting to the edge then it is
usually not a problem, particularly on the right hand side of
the sender.
5. Make sure that metal doors or covers are far enough away
from the sender as well, once everything is closed up the
positioning may change. The symptoms of exposure to large
metal components are usually a non-zero reading when the
tank is empty, or the level appearing to jump suddenly as the
tank is drained or filled.
6. On fresh tanks there is sometimes a potential to not be able
to use all the water in the tank, we suggest you elevate the
fresh sender 1" off the tank bottom and position the top of
the sender to allow for vent position (if the vent is on the side
of the tank). This way you should see '0' before the pump
starts to suck air. Some tanks have a sump style draw system,
in this case there is no concern with unusable water, just allow
709-RVC NLP Manual
Page 29