GAC AFR200 Series Specification sheet

E
NGINE
G
OVERNING
S
YSTEMS
AFR200 Series
Air Fuel Ratio Controller
Governors America Corp., 720 Silver Street, Agawam, MA 01001
Tel: [phone], Fax: [phone]
[e-mail]
www.governors-america.com
PRODUCT USER GUIDE

AFR200 Series, Product User Guide
This document is subject to change without notice.
Caution: None of GAC products are flight certified controls including this item
Copyright © 2010, Governors America Corp., All Rights Reserved
2
PUG4144 D

AFR200 Series, Product User Guide
This document is subject to change without notice.
Caution: None of GAC products are flight certified controls including this item
Copyright © 2010, Governors America Corp., All Rights Reserved
3
PUG4144 D
Table of Contents
1Introduction .......................................................................................................................5
1.1 Certifications..............................................................................................................................................5
2Product Variations.............................................................................................................6
2.1 AFR Product Selection Clarification..........................................................................................................6
2.2 Standard Features.....................................................................................................................................6
3Operational Description....................................................................................................8
3.1 Overview ...................................................................................................................................................8
3.2 Air Fuel Ratio (AFR) Controller Feedback Inputs .....................................................................................8
3.2.1 Pre-Catalytic Converter Oxygen (O2) Sensor....................................................................................8
3.2.2 Manifold Absolute Pressure (MAP) sensor.........................................................................................8
3.2.3 Engine Speed Sensor.........................................................................................................................9
3.3 Speed Control and Protection...................................................................................................................9
3.3.1 Auxiliary (AUX) Speed Trim Input.......................................................................................................9
3.4 Fueling States ...........................................................................................................................................9
3.5 Communication & Configuration .............................................................................................................10
3.5.1 SmartVU Configuration Software .....................................................................................................10
3.5.2 Diagnostics .......................................................................................................................................10
3.6 Optional Sensors.....................................................................................................................................10
3.6.1 Post-Catalytic Oxygen (O2) Sensor .................................................................................................10
3.6.2 Engine Oil Pressure (EOP) Sensor ..................................................................................................10
3.6.3 Engine Coolant Temperature (ECT) Sensor ....................................................................................10
3.6.4 Exhaust Gas Temperature (EGT) Sensor........................................................................................11
3.7 Binary Inputs / Outputs............................................................................................................................11
3.7.1 Power Relay Output..........................................................................................................................11
3.7.2 Malfunction Indicator Lamp (MIL) Output.........................................................................................11
3.7.3 Engine Speed Increment / Decrement .............................................................................................11
4System Interconnect Diagram........................................................................................12
5AFR Components and Optional Equipment..................................................................14
5.1 AFR & Related GAC Components Table................................................................................................14
5.2 Component Selection Information...........................................................................................................15
5.2.1 GAC Actuator Throttle Bodies ..........................................................................................................15
5.2.2 Air-Fuel Mixer / Control Valve Assembly..........................................................................................16
5.2.3 Zero Pressure Gas Regulator...........................................................................................................17
5.2.4 Electronic Gas Lockout Valve...........................................................................................................17
5.2.5 Air Filtration.......................................................................................................................................17
5.2.6 Engine Sensors ................................................................................................................................17
5.2.7 Speed Trim Potentiometers..............................................................................................................17
6Component Information & Installation ..........................................................................19
6.1 AFR 200 Series Controller ......................................................................................................................19
6.1.1 Application Considerations...............................................................................................................20
6.1.2 Installation Instructions .....................................................................................................................20
6.2 GAC Actuator Throttle Body (ATB).........................................................................................................21
6.2.1 Application Considerations...............................................................................................................21
6.2.2 Installation Procedure.......................................................................................................................21

AFR200 Series, Product User Guide
This document is subject to change without notice.
Caution: None of GAC products are flight certified controls including this item
Copyright © 2010, Governors America Corp., All Rights Reserved
4
PUG4144 D
6.3 Air-Fuel Mixer & Control Valve Assembly...............................................................................................22
6.3.1 Application Considerations...............................................................................................................24
6.3.2 Installation Instructions .....................................................................................................................25
6.4 Gas Pressure Regulator (Zero Pressure) ...............................................................................................25
6.4.1 Application Considerations...............................................................................................................26
6.4.2 Installation Instructions .....................................................................................................................27
6.5 Electronic Gas Lockout Valve .................................................................................................................28
6.5.1 Application Considerations...............................................................................................................28
6.6 Air Filtration .............................................................................................................................................28
6.6.1 Application Considerations...............................................................................................................29
7Engine Sensor Information & Installation .....................................................................30
7.1 Magnetic Engine Speed Pickup..............................................................................................................30
7.1.1 Application Considerations...............................................................................................................30
7.1.2 Installation Instructions .....................................................................................................................30
7.2 Manifold Absolute Pressure Sensor (MAP).............................................................................................31
7.2.1 Application Considerations...............................................................................................................31
7.2.2 Installation Instructions .....................................................................................................................32
7.3 Exhaust Oxygen Sensor .........................................................................................................................32
7.3.1 Application Considerations...............................................................................................................33
7.3.2 Installation Instructions .....................................................................................................................34
7.4 Engine Coolant Temperature Sensor (ECT)...........................................................................................34
7.4.1 Application Considerations...............................................................................................................34
7.4.2 Installation Instructions .....................................................................................................................35
7.5 Engine Oil Pressure Sensor (EOP).........................................................................................................35
7.5.1 Application Considerations...............................................................................................................35
7.5.2 Installation Instructions .....................................................................................................................36
7.6 Exhaust Gas Temperature Sensor (EGT)...............................................................................................36
7.6.1 Application Considerations...............................................................................................................37
7.6.2 Installation Instructions .....................................................................................................................37
8Electrical Connections....................................................................................................38
8.1 AFR Connector Definitions......................................................................................................................38
8.2 AFR Wiring Diagram ...............................................................................................................................40
8.3 System Interface Information ..................................................................................................................41
8.3.1 System Power...................................................................................................................................41
8.3.2 Power Relay (2A) Low Side Output (LSO) .......................................................................................41
8.3.3 Speed Selection Inputs.....................................................................................................................41
8.3.4 Communications...............................................................................................................................41
8.3.5 Fuel Valve (Stepper Motor) Control Output......................................................................................42
9AFR Configuration & Calibration Procedure.................................................................43
10 System Diagnostics ........................................................................................................43
10.1 AFR Indication LEDs...............................................................................................................................43
10.2 Fault / Warning Blink Codes....................................................................................................................44
10.3 Diagnostic Information.............................................................................................................................44
10.3.1 Timers...............................................................................................................................................44
10.3.2 AFR Diagnostic Trouble Code Information.......................................................................................44
11 Symptom Troubleshooting.............................................................................................46
12 Specifications..................................................................................................................47

AFR200 Series, Product User Guide
This document is subject to change without notice.
Caution: None of GAC products are flight certified controls including this item
Copyright © 2010, Governors America Corp., All Rights Reserved
5
PUG4144 D
1 Introduction
The Air Fuel Ratio (AFR) 200 series controller provides a comprehensive fuel management system for gaseous-
fueled, spark-ignited engines which incorporates:
•Optimal closed loop air-fuel ratio and delivery control
•Actuator throttle body control
•A built-in engine speed governor
•Diagnostic capability
•Engine sensor and data monitoring
•CAN / serial communication
•Many optional sensor and binary inputs
•Easy configuration and customization using GAC’s SmartVU software
The system is applicable to a wide range of gaseous fueled engines ranging from 1L to 13L+. The AFR200 series
controllers when used in conjunction with the ICM200 (Ignition Control Module) series offers a complete Fuel and
Ignition Management Solution (FIMS) referred to as the FIMS500 system. Each of these controllers has the
ability to work independently of the other in the event of a failure.
The AFR200 series controller is ruggedly designed to be used in a wide variety of engine environments. The
connector, harness and cast aluminum case are all environmentally sealed to IP-67. The AFR is designed to be
highly reliable and includes protection against reverse battery voltage, transient voltages, short circuits and a loss
of engine speed sensor signal or battery supply.
A representation of the AFR controller is shown in the following figure. The AFR has one 35-pin connector and
one 14-pin connector although in some variations of the controller the 14-pin connector will be removed. This
information is covered in greater detail in the following sections.
AFR200 Controller Identification
1.1 Certifications
The AFR system is capable of supporting the strict emission regulations of both the US and Europe; standards
which most of the world follow. Once a system has been calibrated for optimal emissions results, the calibration
can be loaded into subsequent engine packages with favorable repeatability.
GAC Part
Identification Sticker

AFR200 Series, Product User Guide
This document is subject to change without notice.
Caution: None of GAC products are flight certified controls including this item
Copyright © 2010, Governors America Corp., All Rights Reserved
6
PUG4144 D
2 Product Variations
There are a variety of different models of the AFR 200 series depending on the features desired as shown in the
following table.Note that only the unique features are shown in the below table since the controllers share
common standard inputs and features which are covered in greater detail in follow sections.
Product Selection Table
Model
Unique Features
AFR200
1 Oxygen Sensor Input
AFR201
2 Oxygen Sensor Inputs
AFR210
1 Oxygen Sensor Input
1 Exhaust Gas Temperature Input; Type K Thermocouple
AFR211
2 Oxygen Sensor Inputs
1 Exhaust Gas Temperature Input; Type K Thermocouple
2.1 AFR Product Selection Clarification
•Number of Oxygen Sensors: The number of oxygen sensors is either selected as one for pre-catalytic
converter (or no converter) or two (pre- and post-catalytic) if additional diagnostic capability is desired for
the catalytic converter itself.
•Exhaust Temperature Input: The AFR has the ability to protect the engine in the event of an over-
temperature condition using a type K thermocouple sensor placed in the exhaust stream.
2.2 Standard Features
•Optimal Closed Loop Air-Fuel Ratio and Delivery Control:
•Actuator Throttle Body or Universal Actuator Control
•Proprietary, Fast Responding, Non-Linear, Air/Fuel Ratio Control
•Variable O2 Lambda Control Strategy; Engine Speed vs. Load Mapping
•Fail-safe Open Loop Control for Initial Tuning Values and Troubleshooting
•Industrial, Highly Accurate Stepper Motor Integrated with Venturi Mixer
•Programmable Stepper Motor Start Position
•Built-in Engine Speed Governor:
•Multi PID Governing EDG™ Designed to Control Engine Speed with Precise Response to Transient
Load Changes
•Three Fixed Speeds & One Variable Speed
•Overspeed Shutdown Protection
•Speed Ramping from Idle to Operation Speed
•Starting Fuel Control for Lower Engine Exhaust Emissions
•Full PID Adjustment Capability

AFR200 Series, Product User Guide
This document is subject to change without notice.
Caution: None of GAC products are flight certified controls including this item
Copyright © 2010, Governors America Corp., All Rights Reserved
7
PUG4144 D
•Engine Sensor Data Monitoring and Diagnostic Capability:
•Pre- and Post-Catalytic Converter Oxygen Sensor
•Manifold Absolute Pressure (MAP) Sensor 1, 2, or 3 Bar (14.5, 29, 43.5 PSI)
•Magnetic Speed Pickup
•Exhaust Gas Temperature Sensor; Type K Thermocouple
•Oil Pressure Sensor
•Coolant Temperature Sensor
•Inputs and Outputs:
•Power Relay Output (2A)
•Malfunction Indicator Lamp (MIL) Output & Status LEDs
•Speed Increment / Decrement +/- 10 RPM Binary Inputs
•Auxiliary Speed Trim Input
•CAN / Serial RS232 Communication:
•Diagnostic Trouble Code (DTC) Support
•J1939 Data Broadcast
•GAC’s SmartVU Software:
•Data Monitoring / Graphing Functionality
•Easy Configuration and Customization
•Import / Export Calibration Capability
•Advanced Troubleshooting Data
•Diagnostic Timers and Logging Windows
•12 and 24VDC Compatible
•High Reliability

AFR200 Series, Product User Guide
This document is subject to change without notice.
Caution: None of GAC products are flight certified controls including this item
Copyright © 2010, Governors America Corp., All Rights Reserved
8
PUG4144 D
3 Operational Description
3.1 Overview
The AFR’s fuel control algorithm maintains a stoichiometric air-fuel ratio for optimized emissions and engine
performance. Engine speed can be governed in either isochronous or droop modes using GAC’s proprietary
Electronic Digital Governor (EDG) algorithm.
The AFR control operates the closed loop fuel system with five major components:
•Digital precise stepper motor fuel control valve to adjust the flow of fuel into the system
•Static venturi mixer to combine fuel and air to the appropriate mixture
•Electrically controlled throttle body valve or universal actuator to control the amount of air mixture that
enters the engines intake manifold based on engine speed input
•Oxygen sensor to monitor exhaust to determine whether the engine is running lean or rich
•Manifold Air Pressure (MAP) sensor to measure intake manifold pressure (or vacuum)
For added control and engine protection, the AFR can also sense the following optional sensors:
•Second (post-catalytic) oxygen sensor
•Engine Oil Pressure (EOP) sensor
•Engine Coolant Temperature (ECT) sensor
•Exhaust Gas Temperature (EGT) sensor; Type K thermocouple
3.2 Air Fuel Ratio (AFR) Controller Feedback Inputs
The following sensors are mandatory and used by the AFR for closed-loop control of the air fuel ratio and engine
speed governing.
3.2.1 Pre-Catalytic Converter Oxygen (O2) Sensor
The AFR uses a narrow-band oxygen sensor, located after the merge point in the exhaust manifold / plumbing
and before any exhaust conditioners. This sensor output is between 0 and 1V based on the oxygen concentration
in the exhaust gas. The closed loop feedback is accomplished by varying fueling based on engine speed and load
in addition to the oxygen sensor output.
When no signal is received from the O2 sensor, the sensor fails, or the sensor is not at operating temperature
(must be greater than 600°F) as is the case when a cold engine is first started, the AFR orders a fixed
(unchanging) rich fuel mixture. This is referred to as "open loop" operation because no input is used from the O2
sensor to regulate the fuel mixture.
Adaptation is further carried out by a feedback / predictive algorithm which uses customizable PIDs. The
predefined table values are then changed real-time to ensure the desired oxygen sensor voltage set point
(lambda value) is constantly maintained. The air fuel mixture is constantly adjusted which results in a switching
from lean to rich and vice versa in order to operate at peak efficiency and minimize emissions.
Voltages near 0.9V indicate that the fuel mixture is rich and there is little unburned oxygen in the exhaust whereas
voltages closer to 0.1V indicate the mixture is lean. At 0.5V the engine is operating at stoichiometry.
3.2.2 Manifold Absolute Pressure (MAP) sensor
A pressure sensitive electronic circuit inside the MAP sensor monitors the movement of the internal diaphragm
and generates a voltage signal that changes in proportion to intake manifold pressure. This produces an analog
voltage signal that typically ranges from 0.5 to 4.5 volts. The output voltage usually increases when the throttle is

AFR200 Series, Product User Guide
This document is subject to change without notice.
Caution: None of GAC products are flight certified controls including this item
Copyright © 2010, Governors America Corp., All Rights Reserved
9
PUG4144 D
opened and vacuum drops. The Manifold Absolute Pressure (MAP) sensor is a key sensor because it is used to
determine engine load. It is optional if none of the multi-PID functionality is desired.
3.2.3 Engine Speed Sensor
Engine speed information for the speed governing algorithm is usually received from a magnetic speed sensor.
The speed sensor is typically mounted in close proximity to an engine driven ferrous gear, usually the engine
flywheel ring gear. As the teeth of the gear pass the magnetic sensor, a signal is generated which is proportional
to engine speed.
Other speed sensing devices may be used, provided the generated frequency is proportional to the engine speed
and meets the voltage and frequency range specification. The AFR will begin to govern the engine once the RPM
reaches the crank termination set point.
3.3 Speed Control and Protection
The proprietary multiple PID governor control system provides fast and accurate control (+/- 0.25%) of the
engines speed to any dynamic load changes in isochronous or droop operation. When connected to a throttle
body actuator and supplied with a magnetic speed sensor signal the governor portion will direct the engine to the
desired speed setting.
The governor has several built in configurable features: three fixed and variable speed with correlating droop
settings; engine overspeed shutdown protection; speed ramping from idle to operation speed; and starting fuel
control for lower engine exhaust emissions. The three fixed governed speeds and one variable governed speed
are all selectable through two discrete inputs. An additional accessory input is available for connecting to GAC
load sharing modules (generator set option).
The AFR will protect the engine by shutting it down in the event of an engine overspeed, low oil pressure, high
coolant temperature, or high exhaust temperature. These thresholds are all customizable using SmartVU.
Additionally the controller is designed to withstand reverse polarity connections, transient voltage spikes, and
engine speed data loss in the event of a failure.
3.3.1 Auxiliary (AUX) Speed Trim Input
The auxiliary input signal is intended to provide a speed trim input for the engine to synchronize with another
power source / generator. The aux input range is 0-10 volts with a nominal value of 5 VDC. When enabled, the
input tells the governor what speed to set the engine to.
The AFR is configured for a negative slope meaning that a value of 10V will be the lowest engine speed and 0V
will be the highest engine speed. The default window for engine speed adjustment is + / - 10% from the fixed
speed setting.
3.4 Fueling States
During the engine cranking cycle, starting fuel can be adjusted from an almost closed, to a nearly full fuel position.
Once the engine has started, the speed control point is determined by the idle speed set point and the speed
ramping algorithm. The speed ramping functions adjust the engines speed acceleration and deceleration and is
fully customizable by SmartVU.
After engine speed ramping has been completed, the engine will be at its governed operating speed. When at the
desired governed engine speed, the actuator will be energized with sufficient current to maintain the desired
engine speed in a closed loop speed control, independent of engine load (isochronous operation).

AFR200 Series, Product User Guide
This document is subject to change without notice.
Caution: None of GAC products are flight certified controls including this item
Copyright © 2010, Governors America Corp., All Rights Reserved
10
PUG4144 D
3.5 Communication & Configuration
The controller has both RS232 and CANbus communication capability. Communication with SmartVU is done
over RS232 using a serial port or USB to serial converter. The CANbus is typically used to communicate with
other devices such as J1939 capable display devices, and data readers.
3.5.1 SmartVU Configuration Software
The AFR is programmed and calibrated using GAC’s SmartVU configuration software. The SmartVU interface
allows the user the ability to customize engine performance real-time, monitor data, view diagnostic information,
and store configurations. This information is covered in greater detail in later sections.
3.5.2 Diagnostics
The AFR has the ability to diagnose and indicate numerous failure conditions as well as store an extensive fault
history. This information is readily indicated by the Malfunction Indicator Lamp (MIL) output or by the status
indication LEDs on the AFR itself. For more detailed diagnostics the SmartVU diagnostic interface provides a
host of information including engine data, speed vs. load mapping and OBDII P-codes and GAC G-codes. This
information is covered in greater detail in later sections.
3.6 Optional Sensors
The following section covers the optional sensors which are available for interface with the AFR. Note that the
post-catalytic oxygen and the exhaust gas temperature sensor capability are only available with certain variations
of the AFR whereas the engine oil pressure and coolant temperature sensor inputs are available with all
variations.
3.6.1 Post-Catalytic Oxygen (O2) Sensor
An additional narrow-band stoichiometric oxygen sensor can be mounted in or behind the catalytic converter to
monitor converter efficiency. These are referred to as the downstream O2 sensors. A downstream oxygen sensor
works exactly the same as an upstream O2 sensor in the exhaust manifold. If the converter is doing its job and is
reducing the pollutants in the exhaust, the downstream oxygen sensor should show little activity (few lean-to-rich
transitions, which are also called "cross-counts"). The sensor's voltage reading should also be fairly steady (not
changing up or down), and average 0.45 volts or higher. If the signal from the downstream oxygen sensor starts
to mirror that from the upstream oxygen sensor(s), it means converter efficiency has dropped off and the
converter isn't cleaning up the pollutants in the exhaust.
3.6.2 Engine Oil Pressure (EOP) Sensor
The engine oil pressure sensor is used by the AFR in order to diagnose and determine whether or not a low oil
pressure condition exists during engine operation. The setpoint is entered via SmartVU and the AFR will then
shutdown the engine in the event of a failure.
3.6.3 Engine Coolant Temperature (ECT) Sensor
The engine coolant temperature sensor is used by the AFR to gauge engine temperature and alert the operator or
shutdown the engine in the event of an over temperature condition. The GAC offered coolant temperature sensor
is a thermistor where the sensors resistance varies inversely to temperature changes. This number can be
displayed on a scan tool, and may also be used by the instrument panel cluster or driver information center to
display the temperature reading of the coolant.

AFR200 Series, Product User Guide
This document is subject to change without notice.
Caution: None of GAC products are flight certified controls including this item
Copyright © 2010, Governors America Corp., All Rights Reserved
11
PUG4144 D
3.6.4 Exhaust Gas Temperature (EGT) Sensor
The AFR has the ability to monitor a type K thermocouple to determine engine exhaust gas temperature. If the
high temperature threshold is exceeded during operation, the AFR will impose a de-rate in throttle % and will
allow the system to recover once the temperature has returned to the normal operating region. If the temperature
does not decrease over a set time interval the AFR will shut the engine down. These limits and thresholds can be
calibrated within the AFR controller using SmartVU.
3.7 Binary Inputs / Outputs
The following section covers the various low-side (close to ground) outputs and inputs the AFR includes.
3.7.1 Power Relay Output
The AFR includes a 2A low-side binary output for control of the power relay. The power relay is used to provide
power to the oxygen sensor heaters as well as control the shutdown of the engine. This information is detailed
greater in following sections.
3.7.2 Malfunction Indicator Lamp (MIL) Output
The AFR provides an optional Malfunction Indicator Lamp (MIL) output which can be wired to an external fault
lamp or buzzer in order to indicate engine, sensor, or controller malfunctions. This output is triggered to match
the Fault LED on the AFR itself. The max current is 2A and the output is a 12V or 24V high side output. The
blink patterns and fault indication is covered in greater detail in the diagnostics section.
3.7.3 Engine Speed Increment / Decrement
The AFR has two active low binary inputs used to control variable speed increment and decrement. When tied to
ground momentarily each of these inputs will either increment or decrement engine speed by 10 RPM while in
variable speed mode.
Take extreme caution when using this feature since it will allow adjustment through the full range of engine RPM
up to the overspeed setpoint if the limits have not been calibrated.

AFR200 Series, Product User Guide
This document is subject to change without notice.
Caution: None of GAC products are flight certified controls including this item
Copyright © 2010, Governors America Corp., All Rights Reserved
12
PUG4144 D
4 System Interconnect Diagram

AFR200 Series, Product User Guide
This document is subject to change without notice.
Caution: None of GAC products are flight certified controls including this item
Copyright © 2010, Governors America Corp., All Rights Reserved
13
PUG4144 D

AFR200 Series, Product User Guide
This document is subject to change without notice.
Caution: None of GAC products are flight certified controls including this item
Copyright © 2010, Governors America Corp., All Rights Reserved
14
PUG4144 D
5 AFR Components and Optional Equipment
5.1 AFR & Related GAC Components Table
Component GAC Part Number Description
Air Fuel Ratio Controller (AFR)
AFR200 1 x O2Sensor Capable
AFR201 2 x O2Sensor Capable
AFR210 1 x O2Sensor, EGT Capable
AFR211 2 x O2Sensor, EGT Capable
AFR Mating Connectors
EC1501 Connector J1 (35 - PIN)
EC1502 Connector J2 (14 – PIN) *Note this connector is not used on the AFR200
and 210.
Actuator Throttle Bodies
(ATBs) Numerous See information provided in following section.
Connector Included
Air-Fuel Mixer / Control Valves
MXSB20,22,24,26,
28,30-STM
Size 20,22,24,26,28,30 w/ integrated stepper motor
control valve
MXMB40,42,44,46,
48,50 -STM
Size 40,42,44,46,48,50 w/ integrated stepper motor
control valve
Stepper Motor Mating Connector EC1507 4-pin Delphi Mating Connector for Fuel Control
Valve Stepper Motor
Zero Pressure Gas Regulators RPR101 With 3/4" NPT Fittings
RPR102
With 1" NPT Fittings
Oxygen Sensors
SOX102
Heated Narrow-Band 02 Sensor; 12V
SOX103
Narrow-Band, O2 Sensor, 24V
Oxygen Sensor Mating Connector
EC1508
4-pin O2 Sensor Mating Connector; SOX102
EC1520
2-pin O2 Sensor Mating Connector; SOX103
Manifold Absolute Pressure (MAP)
Sensors
SPM200-1B MAP - 1 Bar (14.5 PSI)
SPM201-2B MAP - 2 Bar (29 PSI)
SPM202-3B MAP - 3 Bar (43.5 PSI)
Manifold Absolute Pressure (MAP)
Mating Connector
EC1509 Mating Connector MAP - 1 Bar
EC1510
Mating Connector MAP - 2 Bar
EC1511
Mating Connector MAP - 3 Bar
Engine Oil Pressure Sensor (EOP) SPO100
10 Bar (150 PSI) w/ Knurled Nut, Ring #10 Posts,
1/8-27 NPTF
Engine Coolant Temperature
Sensor (ETC)
STC101
250°F (120°C) w/ Two Male 1/4” Quick Connect
Terminals, 3/8-18 NPT
Exhaust Gas Temperature Sensor
(EGT) STE101
Type K Thermocouple w/ Mini-TC Connector &
Mate, 1/4 NPT
Magnetic Speed Sensors Numerous
See information provided under Engine Sensor
Installation & Information

AFR200 Series, Product User Guide
This document is subject to change without notice.
Caution: None of GAC products are flight certified controls including this item
Copyright © 2010, Governors America Corp., All Rights Reserved
15
PUG4144 D
Speed Trim Potentiometers Numerous
See information provided under Component
Selection Information
Power Control Relay
RLY02-1009
Power Relay Kit, 12V only, 1-pole, N.O.
RLY02-1011
Power Relay Kit, 24V only, 1-pole, N.O.
EC1506
Relay Mating Connector
RS232 PC Interface
EC1516
DB-9 Female Connector & Backshell
EAM204
USB to RS232 Adapter
Fuse Mating Connector Kit
EC1505
Fuse Holder Assembly – ATC
5.2 Component Selection Information
The following sections provide detail on sizing or choosing the various components offered from GAC for the
AFR200 series controller.
5.2.1 GAC Actuator Throttle Bodies
GAC has developed a matrix to help identify the correct bore size for a throttle body. The information needed to
determine the sizing is the engine displacement as well as the operating RPM. When selecting the bore size
ensure that the choice made offers some leeway both upward and downward to provide margin.
For GAC provided actuator throttle bodies refer to the following link to the ATB Application Matrix to select the
correct bore size:
•http://www.governors-america.com/public_file/file/86/Application_Matrix.jpg?1243535515
•Since this information is based on ideal situations the bore selection may need to be changed once
tested in actual application.
For GAC actuator throttle body variations refer to the following link for product information:
•http://www.governors-america.com/throttle_body_actuators.html
•The AFR is only capable of driving a universal actuator or GAC actuator throttle body up to 6A of
continuous current draw. This limits the selection to the T1 and T2 actuator throttle body families
which are available in the following bore sizes:
•T1: 25, 30, 35, 40mm
•T2: 45, 55, 65mm
•AFR installations DO NOT require the feedback version of the ATB which incorporates a position
sensor for accurate control.
•Due to high intake manifold pressure certain applications require internal sealing as well as high
temperature capability.
•GAC offers both 12V and 24V versions of the ATBs so ensure the correct version is selected.

AFR200 Series, Product User Guide
This document is subject to change without notice.
Caution: None of GAC products are flight certified controls including this item
Copyright © 2010, Governors America Corp., All Rights Reserved
16
PUG4144 D
5.2.2 Air-Fuel Mixer / Control Valve Assembly
The following table is used to determine the appropriate air-fuel mixer selection (MX) as cross-referenced to the
ATB bore size for optimal engine performance.
MXSB & T1 ATB / Mixer Compatibility Matrix*
Mixer Type
T1 ATB Size
Mixer P/N Throat Size
(inch)
Throat Size
(mm)
25mm 30mm 35mm 40mm
MXSB20
0.625
15.88
X
MXSB22 0.6875 17.46
X
MXSB24
0.75
19.05
X
X
MXSB26 0.8125 20.64
X
X
MXSB28
0.875
22.23
X
X
X
MXSB30 0.9375 23.81 X
X
T2 ATB / Mixer Compatibility Matrix*
Mixer Type
T2 ATB Size
Mixer P/N Throat Size
(inch) Throat Size (mm) 45mm 55mm 65mm
MXMB40
1.25
31.75
X
MXMB42 1.3125 33.34 X X
MXMB44
1.375
34.93
X
X
MXMB46 1.4375 36.51
X
X
MXMB48
1.5
38.10
X
X
MXMB50 1.5625 39.69
X
*Important Note: The information provided is the recommended pairings of ATB’s and air-fuel mixers with the
most common combination emphasized in bold. The actual application may dictate a different pairing. In some
cases, there are more than one possible choice of mixer for a given throttle body. Contact your GAC
representative for confirmation on mixer sizing prior to ordering.
5.2.2.1 Mixer Nomenclature Clarification
The mixer part numbers are provided as MXSB## and MXMB## with the SB designating Small-Bore and the MB
designating Medium-Bore.
•The MXSB series bolts directly to the T1 GAC ATB family (available up to 40mm)
•The MXMB series bolts directly to the T2 GAC ATB family (available up to 65mm)
Important Note: The ## is provided in 32nds of an inch at the venturi mixer throat. For example, the MXSB20 is
20/32 in. throat diameter.

AFR200 Series, Product User Guide
This document is subject to change without notice.
Caution: None of GAC products are flight certified controls including this item
Copyright © 2010, Governors America Corp., All Rights Reserved
17
PUG4144 D
5.2.3 Zero Pressure Gas Regulator
There are two varieties of Maxitrol Zero Pressure Gas Regulators offered by GAC. These are:
•RPR101 – Maxitrol R500Z – 3/4” NPT Fitting
•RPR102 - Maxitrol R600Z – 1” NPT Fitting
In most cases you can simply select the correct version of the regulator by choosing the size fitting you prefer and
ensuring that the pressure drop is within the allowable range using the provided data.
Important Note: The venturi mixer & fuel control valve assembly may have a different size fitting, select
interconnect plumbing accordingly.
Zero Pressure Gas Regulator Capacities
5.2.4 Electronic Gas Lockout Valve
This is a non-GAC provided item. Refer to the application / installation information in the Component Information
and Installation section for further information on selecting the correct electronic gas lockout valve.
5.2.5 Air Filtration
This is a non-GAC provided item. Refer to the application / installation information in the Component Information
and Installation section for further information on selecting the correct air filtration system.
5.2.6 Engine Sensors
Although each of the sensors offered by GAC has been fully validated and approved for use with the AFR system
there is always the option of using an alternate supplier as long as the sensor is equivalent in electrical
characteristics. The application and installation information provided in following sections provide greater detail
on selecting the appropriate sensors.
5.2.7 Speed Trim Potentiometers
The following information details the various variable speed trim potentiometers available for purchase from GAC.
The following table shows the various part numbers and a brief description of these components. Note that the
greater the resistance and the higher number of turns will provide the greatest precision over speed control.

AFR200 Series, Product User Guide
This document is subject to change without notice.
Caution: None of GAC products are flight certified controls including this item
Copyright © 2010, Governors America Corp., All Rights Reserved
18
PUG4144 D
Speed Trim Potentiometers
GAC Part Number Turns
Resistance
(Ω)
Features
TP510
10
1k
--
TP501
1
5k
Knob Included
TP502
10
5k
Knob Included
TP503
10
5k
Locking Shaft
TP511
10
10k
--
TP509
10
20k
Knob Included
TP508
10
20k
Locking Shaft

AFR200 Series, Product User Guide
This document is subject to change without notice.
Caution: None of GAC products are flight certified controls including this item
Copyright © 2010, Governors America Corp., All Rights Reserved
19
PUG4144 D
6 Component Information & Installation
6.1 AFR 200 Series Controller
The AFR 200 is environmentally sealed and has a wide operating temperature range allowing it to be mounted
directly to the engine on a flat plate in an area that does not exceed the unit’s environmental specifications.A
picture of the controller is provided in the following figure. The AFR200 and 210 will only have the 35-pin
connector (J1) where as the other variations will have both connectors.
AFR200 Series Controller Identification
AFR Dimensions
Dimensions shown as in. [mm]
AFR Status LEDs
GAC Part
Identification Sticker
Connector J1: 35-pin
Connector J2: 14-pin

AFR200 Series, Product User Guide
This document is subject to change without notice.
Caution: None of GAC products are flight certified controls including this item
Copyright © 2010, Governors America Corp., All Rights Reserved
20
PUG4144 D
6.1.1 Application Considerations
•Do not select a mounting location on or near areas of high temperature components such as exhaust
systems and turbochargers.
•The max ambient operating temperature of the controller is 185° F [85° C].
•If the AFR is not mounted to a bulkhead ensure the mounting bracket is designed to withstand vibration
using vibration isolators, dampers, standoffs or multi-point mounting as needed.
•The AFR has been tested to 7G’s @ 20 – 2000 Hz but excessive vibration can cause damage to
harnessing due to chafing and other factors.
•Select a bracket material and geometry that supports the AFR securely without flexing due to
vibration.
•Allow a minimum of 3 in. [76.2mm] in front of the controller to for harness connection and serviceability.
•When selecting a mounting location ensure the AFR status indication LEDs are clearly visible for
diagnostic and troubleshooting purposes.
•Mount the AFR so that the connectors are not facing upward in order to avoid possible water intrusion.
•Select a flat surface or bracket for mounting the AFR to avoid flexing the controller packaging during
installation.
•Mount the AFR in a location clear from walkways and steps so that the controller will not be damaged
during routine maintenance and operation.
•Choose mounting hardware using the dimensions shown (i.e. Diameter < 0.202 in. [5.1mm]).
6.1.2 Installation Instructions
1. Clean the mounting area from any debris prior to mounting the AFR.
2. Mount the AFR to the selected location using a bracket or a direct to bulkhead mounting scheme using
the dimensions and application information provided.
•If stand-offs or vibration isolators are required, make sure these are in place prior to proceeding.
3. Insert the mounting hardware selected into the four holes on the AFR.
•Pre-drill and tap the locations as required prior to installation.
4. Using standard values, torque the selected mounting hardware down to a maximum of 3-6 lb. in. [0.34-
0.68 N•m] without applying excessive force to avoid damaging the mounting tabs or flexing the controller.
•Ensure that each of the mounting bolts / screws is torqued evenly and gradually.