Woodward GECO, Technical Manual, Page: 10 / 90

GECO

Stoichiometric Manual 03554
2 Woodward

Plug-in terminal strip connectors for ease of installation

CSA Listed for Class I, Division 2, Groups A, B, C, and D in Canada and US
*—Modbus is a registered trademark of Schneider Automation Inc.
Definitions of Terms and Abbreviations
atm
°C
catalyst
CLE
closed loop (CL)
duty cycle
ECU
EGO sensor
EGT sensor
equivalence
ratio
°F
GECO
G-lead
HEGO sensor
kPa
kW
kW transducer
Atmosphere (pressure), 14.7 psia
at sea-level (101 kPa, 1.01 bar)
Degree Celsius
Also known as a catalytic
converter, a flow-through chemical
reactor mounted in the exhaust
stream to decrease harmful
emissions; three-way refers to
simultaneous oxidation of carbon
monoxide (CO) and hydrocarbon
(HC) along with reduction of
oxides of nitrogen (NO x ) at fuel
mixtures close to stoichiometry
Closed Loop Enable (switch)
Control using feedback signals
from the controlled parameter
Percent of on time per total on/off
cycle time
Electronic Control Unit
Exhaust Gas Oxygen sensor
Exhaust Gas Temperature sensor
(K-type thermocouple)
Normalized air/fuel ratio used to
compare different fuels relative to
stoichiometry
phi (
φ ) = (A/F)
stoich
/ (A/F)
actual
lambda ( λ ) = 1/phi
Degree Fahrenheit
Gas Engine Control
Ignition pulse output signal (high
voltage) used for engine speed
measurement
Heated Exhaust Gas Oxygen
Sensor
kilopascal (pressure)
kilowatt (power)
A transducer that measures the
output power of the electrical
generator and converts that
measurement to a proportional
4–20 mA signal
lambda ( λ )
lb-ft
lbm/hr/l
LCD
LED
MAP
MAT
Mdot
MPU
N

m
open loop
PC
psi
psia
psig
RPM
RTV
stereo
stoichiometric
TC
W
See equivalence ratio
Pound-feet (torque)
Pounds per hour per liter
(mass flow rate per liter of engine
displacement)
Liquid Crystal Display
Light Emitting Diode
Intake Manifold Absolute
Pressure—an indicator of engine
load
Intake Manifold Absolute
Temperature—used to determine
mixture density
Mass flow rate
Magnetic Pickup speed sensor
Newton-meter (torque)
Control without feedback from any
controlled parameters
Personal Computer
Pounds per square inch (pressure)
psi absolute pressure
psi gauge pressure (over ambient)
Revolutions Per Minute (rotational
speed)
Room Temperature Vulcanizing
(silicone sealers)
Two separate fuel systems for each
bank of cylinders including intake
manifolds, throttles, and carburetors
Chemically balanced mixtures (all
reactants mutually consumed)—in
the case of engine air/fuel mixtures,
just enough air to theoretically burn
all the fuel
Thermocouple (see EGT)
Watt (power)