Dynon Avionics SkyView System Installation Guide - Manual (Page 146)

SV-EMS-220/221 Installation and Configuration
7-34 SkyView System Installation Guide - Revision S
Engine Sensor and Transducer Installation
This section explains the steps required to install and connect all sensors and transducers
supplied by Dynon Avionics. Additionally, connection instructions are given for some sensors
and transducers that Dynon Avionics does not sell, like the tachometer, fuel level, flaps, trim,
and contacts.
All sensors and transducers must be properly defined, mapped, and configured as
described in the EMS Sensor Definitions, Mapping, and Settings Section of this
guide.
Remember to configure the measurement units for your Engine Page as described
in the How to Configure Displayed Units Section.
Engine Sensor Accuracy and Grounding
It is vitally important that all engine sensors, your Dynon SkyView display, your SV-EMS-
220/221 module, and electrical system all share the same ground, and that there is virtually no
measurable voltage between these grounds.
Large currents flow between your alternator and the rest of your aircraft. The ground for these
currents is shared with your sensors. Because of the large currents involved, resistance in
grounds that cannot be seen with a simple multimeter can still lead to significant voltage
offsets. This can lead to errors in sensor readings.
These large currents exist in other places in the aircraft as well, such as between the battery
ground cable and its connection to the airframe, and along the grounding points for the
avionics bus. It is important that all of these ground paths be appropriately sized for the loads
involved, and that the connections be clean, solid, and devoid of contamination.
In particular, be sure to connect a ground wire between your engine block or avionics ground
block and any of the SV-EMS-220/221’s ground pins.
Please note that running a ground wire from the EMS to the engine block may not entirely solve
grounding issue, as this adds just a small wire in parallel with another much larger wire, and the
load will get transferred to this smaller wire, which itself is resistive due to its small size, and
thus no real effect will be seen.
Though dealing with grounding issues can be time consuming and frustrating, errors that are
seen on your Dynon Engine Monitor are caused by points in the aircraft where there is
insufficient grounding. This can lead to weak starting, hot wires, and corrosion. Fixing the
Engine Monitor readings by having a good ground will also lead to a healthier aircraft electrical
system overall.
Tools and Equipment Required
The following list contains commonly used tools and equipment, however some of the tools or
equipment listed below may not apply to your installation.