SkyView System Installation Guide - Dynon Avionics

SV-EMS-220/221 Installation and ConfigurationDepending upon existing equipment and engine type, you have a few options for connectingthe tachometer inputs on the SV-EMS-220/221. The following table revisits the SV-EMS-220/221 pins that are compatible with RPM sources.Pin Wire Color Function32 White/Green Standard RPM Input Left (10+ volts)33 White/Blue Standard RPM Input Right (10+ volts)34 Blue Low Voltage RPM Input Left (< 12 volts)35 Green Low Voltage RPM Input Right (< 12 volts)Table 32–SV-EMS-220/221 RPM InputsSee the relevant subsections below for your particular method. You may connect differenttypes of signals to the two different RPM inputs (e.g., p-lead to Standard RPM Left and a 12 volttransducer to Standard RPM Right).SkyView will display RPM from either the RPM Input Left or the RPM Input Right, whichever isnoticed by the SV-EMS-220 first. If the first RPM signal is lost (such as when one ignition sourcefails, or during a routine mag check), then SkyView will display RPM from the remaining RPMsignal. If your engine only provides one RPM signal, connect it to one of the two RPM Input Leftpins.If a standard RPM input is used, do not connect anything to the low voltage inputof the same polarity (i.e., right or left). If a low voltage RPM input is used, do notconnect anything to the corresponding standard RPM input.Tachometer transducerIf you have a dedicated tachometer transducer (usually with a 12 volt output), you may simplyconnect its output to the Standard RPM Left input on the SV-EMS-220/221. Ensure that youfollow all recommendations given in the manual for your individual tachometer transducer.P-lead pickoff (Lycoming andContinental)If you do not have a dedicated tachometerpickoff, you must follow the instructionsbelow.Use the two included 30 kΩ resistors (colorbands: orange, black, brown, red, brown;connect in either direction) to attach leftand right P-leads to the standard RPM Leftand RPM Right inputs on the SV-EMS-220/221. Connect them as shown in Figure 29. It isimportant to connect each resistor as close as possible to the spot where you tap into the P-lead. This minimizes the length of cable carrying high voltage spikes. Six-cylinder Lycomingengines sometimes need more inline resistance to prevent false readings by the SV-EMS-220/221. If you supply your ownFigure 29–Magneto Pick Off7-32 SkyView System Installation Guide - Revision O