Dynalco AF-900PC User Manual

AF900PC

Air/Fuel Ratio Control System

Installation and Operating Guide

(c) Copyright 2003, Dynalco Controls

All Rights Reserved.

Revision E 01/30/2012

Specifications and information herin are subject to change without notice. Dynalco
reserves the right to make changes to the equipment described herin to improve
function or design. Although the information contained in this manual has been
carefully reviewed and is believed to be reliable, Dynalco does not assume any
liability for special, indirect, incidental, or consequential damages arising out of the
application or use of the equipment described herein. Warranty is limited and
cannot exceed the price paid for the product upon which the warranty is based.

Trademarks

AF900PC, Dynahost, Dynatrend and Dynalink are trademarks of Dynalco.
Windows and Windows XP are registered trademarks of Microsoft Corporation.

Dynalco
5450 N.W. 33
Fort Lauderdale, FL 33309 U.S.A.
Phone [phone]
Fax [phone]
www.dynalco.com

P/N 145F-11993
Rev. E
Dated: January 30, 2012

rd

Avenue, Suite 104

1

CONTENTS

1. Introduction to the AF900PC Pg. 3

2. Theory of Operation Pg. 3

3. System Diagram Pg. 4

4. Specifications Pg. 5

5. Components/Installation Summary Pg. 6

5.1 System Components Pg. 6

5.2 Installation Summary Pg. 6

6. Installation Details Pg. 7

6.1 Mounting the AF900PC Controller Pg. 7

6.2 Mounting the Heated Oxygen Sensor(s) Pg. 8

6.3 Installation of the K type thermocouple Pg. 8

6.4 Installation of M201 Magnetic Pickup for Speed Sensing Pg. 8

6.5 Installation of full-authority fuel valves Pg. 9

7. Wiring the AF900PC Controller Pg. 9

8. Electrical Connections Pg. 9

9. Front Panel Display User Interface Pg. 12

9.1 Front Panel Configuration Scree ns Pg. 12

9.2 FPD Keypad Pg. 13

9.3 FPD Screens Pg. 14

9.4 Navigational Map of RUN Screens Pg. 15

9.5 Navigational Map of SETUP Mode Screens Pg. 16

9.6 FPD SETUP Mode Pg. 17

10. Computer Interface using DynaHost Software Pg. 19

10.1 Control Panel Specifications Pg. 19

10.2 Screen Navigation Pg. 20

10.3 Main Screen Specifications Pg. 23

10.4 Communication Settings Dialogue Pg. 37

11. Computer Interface using Configuration File Pg. 38

11.1 Downloading a Configuration File Pg. 39

11.2 Uploading Configuration to an .spc file Pg. 40

12. Software Operation Pg. 41

12.1 AUTO Mode Pg. 41

12.2 MANUAL Mode Pg. 42

13. Control Software Pg. 42

14. Manifold Air Pressure (MAP) Load Compensation Pg. 43

15. Catalytic Converter Delta Temperature Pg. 45

16. Data Logging Pg. 45

17. Setup Pg. 46

18. Transfer Pg. 47

19. Start Up Procedure Pg. 49

20. Diagnostics Pg. 50

21. Appendix A. - Example of a Configuration File Pg 52

22. Modbus Addresses Pg. 104

2

1. Introduction to the AF900PC

The AF-900PC is a state-of-the-art air/fuel ratio control system for single/dual bank,
spark-ignited, natural gas fueled carbureted engines. The AF-900PC incorporates
an extensive suite of advanced features that intelligently compensate for real-world
sensor and engine conditions.

This sophisticated system maintains the percentage of oxygen (O2) in the engine’s
exhaust gas stream by adjusting the amount of fuel to the carburetor(s). Fuel
valves mounted between the regulator and carburetor adjust the fuel pressure
applied to the carburetor to maintain the desired air/fuel ratio. The AF900PC is
designed to work with rich-burn engine systems using 3-way or NSCR type
catalytic converters.

In these applications it is very important to maintain air/fuel ratio to avoid damage
to the converter, prevent engine damage when fuel BTU content variations cause
the engine to run very rich or lean, and ultimately enable the engine to reduce
emissions.

2. Theory of Operation

Utilizing heated O2 sensor(s) in the exhaust stream (one per bank), the AF-900PC
provides PWM outputs to full-authority fuel valves in order to accurately control
air/fuel ratio over a wide load range. The O2 sensor operates best slightly rich or
lean of a point called stoichiometric, which is an A/F ratio of 16.09:1 for natural gas.
Engines with catalytic converters should be run slightly rich of stoichiometric for
lowest emissions.

The AF900PC implements compensation through an intelligent closed-loop
algorithm which provides smooth control behavior that is adaptable to changing
engine load, speed, fuel quality, ambient temperature and catalytic converter
conditions.

In addition, the AF900PC offers optional intake manifold pressure sensor(s)
capability for further adjustment of the post-catalytic setpoints, allowing the catalytic
converter to maintain emissions over an even wider range of engine loads and
operating conditions.

The AF900PC system monitors the proper operation of all sensor inputs and
controller outputs, flagging errors and changing its operating mode when a fault is
detected.

Equipped with a powerful onboard data logging feature and real-time clock, the
AF900PC has the ability to log controller conditions at either pre-determined times
of day or on a time interval basis. This allows users to automatically capture and
store diagnostic errors and overall system performance internally over any given
period of time. It also aids in troubleshooting hard to catch intermittent system
problems.

The MODBUS communications capability allows remote monitoring of system
performance and status.

3. System Diagram

AF900PC

Engine Diagram

4

4. Specifications

Inputs

Controller
Outputs

Relay
Outputs

Input Power

Sensor Power Out

Display

Data Logging

Communications

Connections
Operating Temperature

Range
Certification

Left Bank O2 Sensor (heated)
Right Bank O
RPM Input (Magnetic Pickup)
RPM Status (Contact Closure)
Left Bank Output (PWM)
Right Bank Output (PWM)
3 Relays, SPDT, rated @ 5A/24VDC, 1A/120VAC, and

0.5A/220VAC
10 – 30 VDC @ 70 Watts Input Power to AF900PC controller

+ 8 VDC Active Magnetic Pickup Sensor Power

Backlit, 4 Line x 20 Character Alphanumeric Display with large

0.36” Characters

Internal 64M Flash Memory and Windows Based DynaTrend
Software to transfer the data to a laptop for viewing and graphing

Hardware: RS-232 / RS-485
Software: DynaHost Laptop Configuration
Modbus
All Two-Part Terminal Blocks

- 30 to + 80 Deg C

CSA Class I, Division 2, Groups A, B, C, D

Sensor (heated)

2

5

5. Components/Installation Summary

5.1 System Components

Included

Single Bank Dual Bank

AF-900PC-3F Air/Fuel Ratio Controller (1) (1)
400A-12959 Pre-Cat O2 Sensor Cable Ass’y (50 ft) (1) (2)
400A-12064 Post-Cat O2 Sensor Cable Ass’y (100 ft) (1) (1)

External Components (purchase separately)
Heated Pre-Cat Oxygen Sensor (Bosch p/n 15718) (1) (2)

Full-Authority Fuel Valve (1) (2)

Optional External Components (purchase separately)

M201 Magnetic Pickup for speed sensing (1) (1)
C101-XX Pickup Cable for M201 (1) (1)
Heated Post-Cat Oxygen Sensor (Bosch p/n 15718) (1) (1)
K type thermocouples (ungrounded) (2) (2)

5.2 Installation Summary

1. Mount AF900PC Controller

2. Install Oxygen Sensor(s) in each engine exhaust bank

3. Run cables for Oxygen Sensors to controller (conduit must be used for Division 2
certification).

4. Install full-authority fuel valve(s)

5. Wire power to controller (10-30 VDC)

6. Install pickup for engine run signal and wire to controller. (Note: A contact closure run
signal may be used instead of the magnetic pickup).

7. Wire controller Alarm, Shutdown, and Auxiliary relay outputs to engine panel
shutdown and warning devices as required.

6

6. Installation Details

6.1 Mounting the AF900PC Controller

The AF900PC Controller (Fig. 1) should be mounted at “eye level” in an accessible
location for easy display and keypad interface. The controller must be mounted in
surroundings where vibration is minimal and the ambient temperature does not
exceed 80 Deg C. A typical mounting location is on the side of the engine control
panel. A shock mount kit should always be used while mounting. All wiring enters
the controller through the bottom of the enclosure. There are three holes for ½”
conduit entry. All wiring is connected to the main board using removable terminal
blocks for ease of wiring and controller replacement.

NOTE: Installation requires four mounting holes.

8.0

13.5

10.25

12.25

12.8

Front View Inside View

Air/Fuel Ratio Control System

AF900PC

Fig. 1

7

6.2 Mounting the Heated Oxygen Sensor(s)

The heated oxygen sensor(s) should be mounted in the exhaust pipe as close to
the engine exhaust manifold as possible. A single bank engine requires only one
sensor. For dual bank “V” engines, the left and right bank sensors should be
mounted as close to the engine exhaust manifold as possible to eliminate cross
talk between the two banks.

CAUTION: The sensor(s) must be mounted where the temperature on the
outer shell does not exceed 400O F (204O C).

Above 400oF, sensor life will deteriorate rapidly and output voltage will be affected.
The sensor(s) should be mounted on a horizontal plane or above horizontal to keep
water from accumulating on the sensor tip. The sensor(s) should also be mounted
where they are accessible as sensor replacement is recommended every 2000
hours. It is recommended a fitting with 18mm x 1 ½ internal threads be welded into
the exhaust pipe for each sensor to be mounted. This will provide a flat mounting
surface for the sensor to avoid exhaust leaks. Sensors should be mounted with an
anti-seize compound on the threads.

NOTE: Recommended torque for mounting the sensors is 28 – 38 ft-lbs.
The conduit for the oxygen sensor should be routed to avoid close proximity to high

tensions ignition cables and coils to minimize potential EMI interference. Ignition,
flow control valve, and power wiring must not be placed in the same conduit with
oxygen sensor wiring. The conduit should also be routed where temperature does
not exceed 200oF.

6.3 Mounting the K type thermocouples (ungrounded must be used)

Optional thermocouples may be installed in the exhaust pipe to monitor pre and
post catalyst temperatures. The AF900PC will also calculate the differential (or
delta) temperature to help ensure proper catalyst operation. An NPT tap should be
used to tap the hole for the thermocouple. An adjustable fitting on most
thermocouple probes will allow proper insertion depth into the exhaust stream. The
thermocouples should be connected to the AF900PC terminal block using
thermocouple extension wire to eliminate erroneous readings.

6.4 Installation of M-201 Magnetic Pickup for Speed Sensing

The M201 magnetic pickup detects engine speed by sensing flywheel gear teeth as
they pass by. The pickup must be mounted on a bracket or flywheel cover so that it
is perpendicular to the face of the flywheel teeth it is sensing. The M201 requires a
5/8-18 UNF thread for mounting. The gap between the pickup pole piece and the
gear teeth should be set to 0.020” to 0.030”. Once the gap has been set, the pickup
should be secured with the lock nut. The M201 should be connected to the
AF900PC with a C101 pickup cable/connector.

8

6.5 Installation of the full-authority fuel valves (one per bank)

The full-authority fuel valves are to be mounted between the fuel regulator and
carburetor fuel inlet, as close to the carburetor inlet as possible.

7. Wiring the AF900PC Controller

All wiring to the AF900PC enters the controller through three (3) conduit openings
in the bottom and connects to three (3) double row terminal strips on the bottom of
the controller main board. The terminal strips unplug from the main board for ease
of controller wiring and replacement. The main board cover plate shows the
location of the terminal strips.

Wiring for terminal strip TS1 should enter through the left conduit opening.
Wiring for terminal strip TS2 should enter through the center conduit opening.
Wiring for terminal strip TS3 should enter through the right conduit opening. This

will separate the millivolt signal levels on TS1 and TS2 from the power, output, and
relay wiring on TS3.

8. Electrical Connections

The Fuel Valves must be configured for single demand, PWM control, and low side
drive.

Terminal Strip

TS1

Bottom Row

TS1-1
TS1-2
TS1-3
TS1-4
TS1-5
TS1-6
TS1-7
TS1-8
TS1-9

Left Bank Oxygen Sensor Output +
Left O2 Sensor Cable - (Black and Shield)
Right Bank Oxygen Sensor Output +
Right O2 Sensor Cable - (Black and Shield) (DB only)
Post-Catalyst Sensor Cable + (White)
Post-Catalyst Sensor Cable – [Black (paired with white) and shield]
Speed Contact Closure + (Required if speed magnetic pickup is not used)
Speed Magnetic Pickup +
Speed Magnetic Pickup - and shield (for speed contact closure if used)

Description

9

Terminal Strip

TS1

Top Row

TS1-10
TS1-11
TS1-12
TS1-13
TS1-14
TS1-15
TS1-16
TS1-17
TS1-18

Pre-Catalyst Thermocouple + (Yellow)
Pre-Catalyst Thermocouple - (Red)
Post-Catalyst Thermocouple + (Yellow)
Post-Catalyst Thermocouple - (Red)
Left Exhaust Thermocouple + (Yellow)
Left Exhaust Thermocouple - (Red)
Right Exhaust Thermocouple + (Yellow) (DB only)
Right Exhaust Thermocouple - (Red) (DB only)
Not Used

Terminal Strip

TS2

Bottom Row

TS2-1
TS2-2
TS2-3
TS2-4
TS2-5
TS2-6
TS2-7
TS2-8
TS2-9
TS2-10

TS2-11
TS2-12

Not Used
+8 VDC Pickup Power for Active Speed Pickup (Optional)
Left & Right Bank Valve Power Common
Left Manifold Air Temperature (MAT) Thermocouple + (Yellow) (Optional)
Left Manifold Air Temperature (MAT) Thermocouple - (Red) (Optional)
Right Manifold Air Temperature (MAT) Thermocouple + (Yellow) (Optional)
Right Manifold Air Temperature (MAT) Thermocouple - (Red) (Optional)
Left Manifold Air Pressure (MAP) Sensor Input (+)
Left Manifold Air Pressure (MAP) Sensor Input (-)
DC Power for Left and Right Manifold Air Pressure (MAP) Sensors
(Factory set to Input Supply Voltage but jumper selectable to 5.0 VDC)
Right Manifold Air Pressure (MAP) Sensor Input (+)
Right Manifold Air Pressure (MAP) Sensor Input (-)

Terminal Strip TS2, Top Row
No Connections Currently Used

Terminal Strip

TS3

Bottom Row

TS3-1
TS3-2
TS3-3
TS3-4
TS3-5
TS3-6
TS3-7
TS3-8
TS3-9

Left Bank + PWM Valve Position Control
Left Bank Valve +12/24 DC Power
Right Bank + PWM Valve Position Control
Right Bank Valve +12/24 DC Power / Right Bank Oxygen Sensor Heater ­Left & Right Bank Oxygen Sensor Heater ­Left & Right Bank Oxygen Sensor Heater +
Not Used
+10 to 30 VDC System Power In @ 70 Watts (#16 AWG wire required)
DC Power Common (#16 AWG wire required)

Description

Description

Description

10

Terminal Strip

TS3

Top Row

TS3-10
TS3-11
TS3-12
TS3-13
TS3-14
TS3-15
TS3-16
TS3-17
TS3-18

NOTE: Relay contacts are shown in the de-energized state.

Alarm Relay Common
Alarm Relay Normally Closed
Alarm Relay Normally Open
Shutdown Relay Common
Shutdown Relay Normally Closed
Shutdown Relay Normally Open
Auxiliary Relay Common
Auxiliary Relay Normally Closed
Auxiliary Relay Normally Open

Description

This terminal strip contains the contacts for the alarm, shutdown, and auxiliary
relays. These contacts are isolated and may be connected to engine shutdown
devices (such as the panel annunciator) or warning devices as required. Any of the
AF900PC thirty-nine trip channels may be programmed to energize one of the
three relays. The SPDT relay contacts are rated @ 5A/24VDC, 1A/120VAC, and

0.5A/220VAC.

11

9. Front Panel Display User Interface

The AF900PC requires the user to configure a variety of parameters. By
performing one of three procedures below, parameters may be configured.

1) Using interface via the SETUP key (password required), keypad, and a 4x20
display.

NOTE: A limited number of parameters are available in the setup screens
of the AF900PC. Using a laptop to configure the AF900PC is
recommended.

2) Using DynaHost multiple laptop configuration screens via a laptop or PC.

3) Using DynaHost, a text editor (Windows Wordpad) and editing the
downloaded file (AF900PC.SPC) via a laptop or PC.

9.1 Front Panel Configuration Screens

The AF900PC Front Panel Display (FPD) user-interface consists of a 4-row by 20­column LCD display (LCD); a 13-key custom keypad; and two LEDs to indicate
ALARM and SHUTDOWN.

12

9.2 FPD Keypad

The custom keypad consists of the following keys:

Four screen-specific Soft Keys are located
directly under the LCD. These keys navigate to
other screens or perform specific actions as
indicated in the last line of the LCD.

SETUP Key enters SETUP Mode.
ESC Key navigates up one menu-level; exits

SETUP Mode; returns to the Main Title Screen;

or cancels certain actions. (Note: To exit SETUP
Mode or return to Title Screen, the customer
must press and hold the ESC Key for three or
more seconds.)

UP, DOWN, LEFT, and RIGHT Keys select or
modify values in SETUP Mode.

ENTER Key accepts modified values changed in
SETUP Mode.

RESET Key resets AF900PC fault conditions

.

13

9.3 FPD Screens

The LCD displays information to the user, grouping the information into screens.
Each screen displays a specific set of information to the user. To change screens,
the user must navigate to the desired screen using the indicated Soft Keys.

The AF900PC will display a title screen upon power up.

DYNALCO CONTROLS

AF900PC

V x.yy

The title screen displays a banner and indicates the current software version for
five seconds before displaying a main status screen. To return to the title screen,
the user must press and hold the ESC key for three seconds.

The main user screens are the Main Status Screen, Pre-Cat Status Screens, Post­Cat Status Screens, Temperature Screens, and MAP Screen. The main status
screen displays the current engine/air-fuel control status (STOPPED, START,
MANUAL, AUTO, etc.) and any current ALARM or SHUTDOWN fault conditions.
The pre-cat status screens display the current pre-cat status and fuel valve
opening percentage. The post-cat status screen displays the current post-cat
status. The temperature screens display all measured engine temperatures. The
MAP screen displays the manifold air pressure(s) and engine RPM.

The SETUP mode screens allow authorized operators to view and/or adjust
software setpoints.

NOTE: Title Screen is not accessible in SETUP Mode.
A navigational screen map layout for the user RUN screens is shown on page 14.
A navigational screen map layout for the SETUP mode screens is shown on page

15.

14

9.4 Navigational Map of RUN Screens

15

9.5 Navigational Map of SETUP Mode Screens

16

9.6 FPD SETUP Mode

1) To enter SETUP mode, press the SETUP key on the FPD.

2) Enter current SETUP password.

NOTE: A four character default password “1 2 3 4” is pre-assigned prior to
shipping. This password may be changed using the DynaHost software to
change parameter 6112.0, if desired. Passwords may be up to eight
characters in length using the digits 1, 2, 3, or 4 only.

3) Enter password using the Soft Keys labeled “1 2 3 4”. A solid asterisk (*) will
appear for each entered character, while a blinking asterisk (*) indicates additional
characters may be entered.

4) Press ENTER for SETUP Mode.

17

From the SETUP menu the user may navigate to setpoint screens (screens that
allow you to change values) by using the Soft Keys. The user may view and/or
modify setpoint values as follows:

1. Navigate to the desired setpoint screen.

2. Press the ENTER key to enter setpoint select mode. The first setpoint
on the screen is now enclosed in angle brackets, i.e. >SETPOINT<.

3. Press the UP/DOWN keys to select the setpoint to modify. The angle
brackets will move from one setpoint to the next for each UP/DOWN key
press.

4. Press the ENTER key to enter setpoint modify mode. The bracketed
setpoint will blink indicating that the operator may now modify its value.

5. Press the UP/DOWN keys to increment or decrement the setpoint value.
The increment/decrement rate may be changed by selecting the desired
rate displayed above the appropriate Soft Key.

6. Press the ENTER key to save the modified setpoint value; press the
ESC key to cancel the modified setpoint value and restore the original
value.

7. Press the ESC key to exit setpoint select mode and return to SETUP
mode screen navigation.

To exit SETUP mode, user must press and hold the ESC key for three seconds. All
modified setpoint values will be stored to memory while display shows the
following:

CONFIGURATION
PARAMETER STORE
IN PROGRESS

Once the SETUP configuration is stored to memory, the AF900PC returns to the
operator screens.

CAUTION: Power must remain normal during the storing process. A failure of
power during “In Process” memory storing will result in the loss of all data
storage and will bring the AF900PC back to factory defaults.

18

10. Computer Interface using DynaHost Software

DynaHost software provides serial communication between a PC or laptop and the

AF900PC. DynaHost will run on a PC with 133MHz Intel Pentium processor, 32
MB of RAM, and a minimum of 100MB of hard disk space. DynaHost is compatible
with Windows 95/NT/98/2000/XP.

The AF900PC must be connected via a standard RS-232, 9-pin, male-female,
serial communication cable. The HOST software communicates
to the AF900PC via Dynalink, Dynalco Control’s ASCII-based serial communication
protocol.

When the program is running there are two major sections: the Control Panel and

the Current Screen.

10.1 Control Panel Specifications

The Control Panel is located at the top of the application screen on the laptop or
PC and allows the user to view the status of the host application, showing the
communication settings and status.

Control Panel (Connected)

Figure 1A

The Control Panel above (Fig. 1A) shows an active communication which allows
the user to navigate through the multiple screens (Main, O2 Health, Learn, Data
log, Trip 1, Trip 2, AI Config, Pre-Cat Cfg, Post-Cat Cfg, RPM Cfg and DynaTrend).

The Control Panel also contains the basic commands:

• Power: Closes the host application.

• Upload: Uploads the current configuration of the AF900PC to a configuration file

(.spc).

• Download: Downloads a configuration file (.spc) to the AF900PC.

• Store: Stores the current configuration.

• Recall: Recalls the last configuration stored.

• Cmd: Sends a command to the AF900PC.

• Resp: Shows the response to a command sent to the AF900PC.

• Screen Buttons: Show the current screen being displayed and allows you to

switch to other screens.

19

The Control Panel in Fig. B shows an inactive communication by displaying a red
“X” across the communication line.

Control Panel (Disconnected)

Figure 1B

10.2 Screen Description

A yellow highlighted button, as shown in Fig. 1B, displays the current screen you
are in. Within each screen you can display information by using the following
controls:

Toggle Button: Represents 2-state parameters. Place the mouse over the button
to the left of text (Figure 2) to see the current state and click on the button to toggle
the state. The button will be green when enabled, black when disabled.

NOTE: The parameter number is displayed when you place the mouse over
the label.

(Disabled) (Enabled)

Toggle Button

Figure 2

Read/Write Green Display: A parameter (Figure 3) which may be modified by
typing a value and pressing ENTER.

NOTE: The parameter number is displayed when you place the mouse over
the label.

Type in value

Green Display

Figure 3

and press

<enter>.

20

Read Only Blue Display: A parameter (Fig. 4) that can only be read.

Blue Display

Figure 4

Combo Box Display: A parameter (Figure 5) modified by selecting one of the

options displayed when you click on the drop-down button.

NOTE: The parameter number is displayed when you place the mouse over
the label.

Combo Box Display

Figure 5

Grid Display: A matrix of green displays (Fig. 6). Some parameters may be

modified by typing in the value and pressing ENTER (press backspace to delete
the current value).

Grid Display

Figure 6

21

Scope: Traces the value of up to two numeric parameters in real time domain. The
user may select parameters to trace by dragging the probe (Figure 7) and dropping
it in the display (blue or green). Minimum and maximum ranges and the
time/division may also be changed. The scope may be enlarged to occupy the
entire screen by clicking on the zoom in button on the scope. The scope will update
much faster when zoomed in because the communications link will request only the
two parameters displayed on the scope.

Take the probe

and Drag and

Dropt it on a

display…

Scope

Figure 7

22

10.3 Main Screen Specifications

MAIN SCREEN

Shows the system and alarm status, the current speed and the main parameters of
the pre-catalyst (left and right banks) and post-catalyst
(Fig. 8). There are also two scopes to plot up to 4 parameters in real time.

In addition, the following parameters may also be changed from the main screen:
Mode: The controller may be changed between AUTO and MANUAL mode by

clicking on the drop down MODE menu and selecting the desired operating mode.
Left and Right Bank O2 Setpoint Req. (V): The pre-catalyst O2 initial setpoint
request voltage may be changed by clicking into the value, deleting the old value,
and entering the new value. Typical operating range is 0.700 to 0.900V.

Post-Catalyst O

Setpoint Req. (V): The post-catalyst O2 initial setpoint request

2

voltage may be changed by clicking into the value, deleting the old value, and
entering the new value. Typical operating range is 0.650 to 0.850V
Left Bank, Right Bank, and Post-Catalyst Enable: Left bank, right bank, and
post-catalyst control may be enabled or disabled by clicking the ENABLE button. If
the button is green, the control is enabled.

Main Screen

Figure 8

23

OXYGEN SENSOR HEALTH SCREEN

The O2 Health Screen (Fig. 9) shows parameters related to sensor health
measurement.

Descriptions of the parameters are as follows:

EU: Displays the current voltage input from each O2 sensor.
ADC: Displays the A/D converter counts from the last sensor input measurement.
Test: Displays the A/D converter counts from the last sensor test measurement.
Raw: Displays the last calculated sensor health for each sensor.
Health: Displays the filtered sensor health for each sensor.
Filter: Programmable parameter sets the filter time constant for the sensor health.

With the maximum value of 1.0, there is no filtering and each sensor test becomes
the new Health value. With the default filter value of 0.01, each new sensor reading
becomes 1/100th of the Health value. In other words, a smaller filter value means
more filtering.
Time (sec): Determines time interval (in seconds) at which sensor health test will
be performed. Sensor Health test is performed every 60 seconds with the default
value of 60.

Oxygen Sensor Health Screen

Figure 9

24

LEARN SCREEN

The Learn Screen (Fig. 10) displays the post-catalyst offset and valve learn tables
created during the MAP programming procedure. MAP pressure and post-catalyst
setpoint values are also shown on this screen. MAP programming may only be
initiated from the AF900PC front panel and will be discussed later in the manual.
Each new point programmed will be entered into the proper place on the table
according to the MAP pressure. The PC offset and valve pos % will change linearly
between points on the table. A point may be deleted from the table by clicking into
the En for that point, deleting the En with the backspace key, and entering DIS.
The PC offset and valve pos % for any point may be changed by deleting the old
value and entering a new value. The MAP values in the tables cannot be altered.

Learn Screen

Figure 10

25

DATA LOG SCREEN

This screen (Fig. 11) sets up the data log system and current date/time.
Data log parameters may be modified as follows:
Current Date/Time: The time and date may be changed by deleting the old value

and entering a new value as required.
Data Log Schedule: Up to ten (10) daily data log times or a periodic data log
interval may be used. The unit may also be set up for one (1) periodic interval time
and up to nine (9) daily log times.

To enable periodic mode data logging:

1. Enter the desired data log interval.

2. Select PERIODIC mode from the drop down menu.

3. Click the EN button for that channel.

To enable daily data logging:

1. Enter the desired data log time.

2. Select DAILY mode from the drop down menu.

3. Click the En button on that channel.

NOTE: Data Log may occur as often as once per second.

Data Log Screen

Figure 11

26

Log Parameter List: The Log Parameter List (Fig. 11) shows the most important
controller parameters being data logged. Disable by clicking the En buttons for any
parameters you do not wish to data log. Enter “0” for the Chart # for any
parameters where an excel chart is not required.

NOTE: Parameters having no numerical value (such as Status) must be
assigned to chart # 0.

NAME shows the parameter name as it appears on the header on the excel

spreadsheet and on the excel charts. The names may be edited if desired.
If you wish to log a parameter not shown:

1. Enter the parameter number and index.

2. Enter the parameter chart #.

3. Enter the parameter name.

The parameter number and index may be found by placing the cursor over the
name of the parameter. The index is the decimal value of the parameter.

NOTE: Enter 255 for the index if the parameter does not have a decimal value.
Flash Memory: This section, shown at the bottom of Fig. 11 of the data log screen,

shows the status of the Onboard Flash Memory. “# Logs Stored” indicates the
number of data logs which have occurred since the last memory reset. “Capacity”
shows the maximum number of data logs required to fill the memory. To “reset”
memory, type “new card” in the Reset box and press enter. The flash memory will
be reset when the next data log occurs. All previously recorded data on the flash
memory will be lost upon reset.

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NOTE: The following descriptions apply to the Trip 1 and Trip 2 Screens
TRIP SCREEN 1

A screen (Fig. 12) used to setup the trip action for pre-catalyst system faults. The
screen shows all faults set to Alarm and Data Log.

Trip Mode: Selects the action, from the drop down menu, which will be taken by
the controller when the fault occurs. To make best use of the system diagnostics, it
is recommended that all trips be programmed to Alarm or Shutdown so the
operator will be alerted if a fault occurs. Faults that are critical to the engines
health, such as high catalyst temperature, should be configured to Shutdown so
the shutdown relay contacts may be used to trip the panel annunciator.

Disabled (DIS): The trip is disabled and no action will be taken.
Alarm (ALM): Trips the Alarm Relay, flashes the Alarm LED, and shows the fault

on the LCD display.

Trip Screen 1

Figure 12

Shutdown (SD): Trips the shutdown relay, flashes the shutdown LED, and shows

the fault on the LCD display.
Auxiliary (AUX): Trips the auxiliary alarm when fault occurs.

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Log: Click the Log button “ON” to force a data log to internal flash memory when
the fault occurs.
Value: This column displays the current value of all trips that have a numeric value.
The value displayed is after the appropriate filters have been applied.
Threshold: This column displays the trip threshold value for all trips that have a
numeric value. To change a threshold value, click into the parameter and edit it.
Delay: This column indicates the delay time in seconds or minutes between the
fault occurring and the trip being actuated. All delay times may be edited and have
a range of 0 to 240.

Status: Indicates whether each trip is in the “Fault “ or “No Fault” condition.
TRIP SCREEN 2

This screen (Fig. 13) is used to setup the trip action for post-catalyst and catalytic
converter system faults.

Trip Screen 2

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Figure 13