SV-EMS-220 Installation and Configuration
SkyView System Installation Guide - Revision K 7-37
wizards (SETUP MENU > HARDWARE CALIBRATION > EMS CALIBRATION).
Once a capacitive fuel level sensing system is calibrated for a certain type fuel, only
that fuel should be used and the aircraft should be placarded for such. For example,
ethanol has a dielectric constant much different than 100LL or Auto Fuel. If
calibrated for 100LL, then by using Auto 10% Ethanol in the tanks the indications
could off by 50%.
It is important to understand that fuel level measurements are subject to the
physical limitations of the sensor. Depending on your fuel tank and sensor
geometry, there may be some immeasurable fuel at either or both ends of the fuel
level sensors’ range. SkyView’s fuel calibration process is designed with this in
mind, and always takes the conservative approach to ensure that it does not report
erroneous fuel readings that might indicate that there is more fuel on board than
there actually is. The end result is that you may experience fuel readings at “full”
that are numerically less than the physical capacity of the tanks, and in this case
you may also see no apparent change in fuel level readings when the sensor is
maxed out on the full side. Similarly, on the empty side, you may see a zero
quantity indication before the tank is truly empty if the sensor has reached the
bottom of its travel or measuring capability when the tank still in fact has fuel in it.
Resistive fuel level sensor
You may connect as many resistive fuel level sensors to the SV-EMS-220 as open general
purpose inputs will allow. We recommend that pins 20 and 21 of the SV-EMS-220 D37 are used
before other general purpose inputs.
Capacitive fuel level sensor
Capacitive fuel level sensors are only supported on pins 8, 22, and 31 on the SV-EMS-220 D37.
Capacitive sensors need to output a variable voltage within the ranges of 0-5 volts DC.
First, supply the sensor with power according to the manufacturer’s instructions. If the sensor
manufacturer requires a sensor calibration, perform that calibration first. Be sure to configure
the firmware to recognize the capacitive fuel level sensor on the enhanced general purpose
inputs.
If you are installing Dynon’s Capacitance-to-Voltage Converter (most commonly used with the
capacitive plates in some RVs), please read the Capacitance-to-Voltage Converter installation
instructions.
Note that SkyView displays are typically preconfigured to use resistive probes. Using capacitive
sensors instead of resistive probes requires that you change EMS settings in a few places. First,
change the pins used for fuel quantity via the SETUP MENU > EMS SETUP > PIN SENSOR INPUT
MAPPING… menu. Then, delete the default fuel quantity widgets from each screen layout
under SETUP MENU > EMS SETUP > SCREEN LAYOUT EDITOR. Finally add, the new fuel quantity
widget(s) that will be available for the capacitive probes.
To Next Page
Loading...
