Lancair Columbia 400 Information Manual page 216

Section 7
Description of the Airplane and Systems Columbia 400 (LC41-550FG)
The ammeter is selectable to show either the condition of the batteries or the alternators. When
power is first applied, the indicator defaults to the "BATT" indicator. When the button on the
lower left side of the instrument is pressed, the indicator switches to the "ALT" indicator.
Pressing the button will toggle between each indication. When the battery mode is selected, a
white light illuminates "BATT". When the alternator mode is selected, a white light illuminates
"ALT".
The range of the indications run from a + 60 amps to – 100 amps in 30 amp increments. While
there is no placarded operating range, under most conditions the instrument should indicate a
positive charging state. The master switches for the left and right bus systems must be on for the
ammeter to operate.
Tachometer – The tachometer is in the engine instrument panel in the center-right position.
Changes in RPM settings are displayed on the tachometer in increments of 100 RPM with the red
line at 2600 RPM. A green arc indicates the range for normal operations, 2000 to 2500 RPM, and
a white arc permitting limited time operation (during climb) from 2500 to 2600 RPM. A red
radial is located above 2600 RPM. The gauge is electronically operated and translates the rotor
speed of the right magneto into an equivalent engine RPM reading. Since the tachometer is
electrically powered, it will not display a reading with the master switches turned off.
Oil Temperature – The oil temperature gauge is in the engine instrument panel in the bottom-
left position. The instrument is a dual presentation gauge with the oil temperature gauge on the
left and oil pressure gauge on the right. The gauge measures oil temperature in degrees
Fahrenheit (°F) in 20°F increments. The normal operating limits (Green Arc) displayed on the
gauge range from 170°F to 220°F with a red radial upper limit of 240°F. The thermal bulb,
which is the source point for measurement of oil temperature, is located near the oil cooler.
Power for the temperature gauge is supplied by the airplane's electrical system, and the oil
temperature gauge will not operate with the master switches turned off.
Oil Pressure – The oil pressure gauge is in the engine instrument panel in the bottom-left
position. The instrument is a dual presentation gauge with the oil temperature gauge on the left
and oil pressure gauge on the right. The gauge measures oil pressure in pounds per square inch
(psi) in increments of 10 psi. The normal operating limits (Green Arc) displayed on the gauge
range from 30 psi to 60 psi. There is a red radial located at 10 and 100 psi. An electrical
transducer mounted to the oil cooler converts pressure changes into electrical voltages. Power for
the transducer is supplied by the airplane's electrical system, and the oil pressure gauge will not
operate with the master switches turned off.
Cylinder Head Temperature (CHT) – The CHT gauge is in the engine instrument panel in the
bottom-right position. The instrument is a dual presentation gauge with the turbine inlet
temperature (TIT) gauge on the left and CHT readings on the right. The CHT gauge displays
cylinder head temperature in degrees Fahrenheit (°F). The green arc or normal operating limits,
range from 240°F to 420°F. The yellow arc ranges from 420°F to 460°F with a red line above
460°F. The source of the temperature reading is a direct measurement from a bayonet probe in
the No. 2 cylinder, which is normally the hottest cylinder. While the CHT is a voltage-generating
temperature indicator, commonly referred to as a thermocouple, the transmitting unit uses the
electrical system of the airplane, and the gauge will not operate if electrical power is lost or the
master switches are turned off.
RC050002 Initial Issue of Manual: November 10, 2004
7-24 Latest Revision Level/Date: -/11-10-2004