Installation guide

SV-EMS-220/221 Installation and Configuration
SkyView System Installation Guide - Revision R 7-37
Pin
Wire Color
Function
34
Blue
Low Voltage RPM Input Left (< 12 volts)
35
Green
Low Voltage RPM Input Right (< 12 volts)
Table 34–SV-EMS-220/221 RPM Inputs
See the relevant subsections below for your particular method. You may connect different
types of signals to the two different RPM inputs (e.g., p-lead to Standard RPM Left and a 12 volt
transducer to Standard RPM Right).
SkyView will display RPM from either the RPM Input Left or the RPM Input Right, whichever is
noticed by the SV-EMS-220 first. If the first RPM signal is lost (such as when one ignition source
fails, or during a routine mag check), then SkyView will display RPM from the remaining RPM
signal. If your engine only provides one RPM signal, connect it to one of the two RPM Input Left
pins.
Pin 32 and 34 are both LEFT RPM input. Use one, or the other, but not both.
Pin 33 and 35 are both RIGHT RPM input. Use one, or the other, but not both.
Tachometer transducer
If you have a dedicated tachometer transducer (usually with a 12 volt output), you may simply
connect its output to the Standard RPM Left input on the SV-EMS-220/221. Ensure that you
follow all recommendations given in the manual for your individual tachometer transducer.
P-lead pickoff (Lycoming and Continental)
If you do not have a dedicated tachometer
pickoff, you must follow the instructions
below.
Use the two included 30 kΩ resistors (color
bands: orange, black, brown, red, brown;
connect in either direction) to attach left
and right P-leads to the standard RPM Left
and RPM Right inputs on the SV-EMS-
220/221. Connect them as shown in Figure
31. It is important 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
Lycoming engines sometimes need more inline resistance to prevent false readings by the SV-
EMS-220/221. If you supply your own resistors, they need not be exactly 30 kΩ. Additionally,
both 1/4W and 1/2W resistors are acceptable to use.
Figure 31–Magneto Pick Off