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Released Application Note 51272 (Revision C, 2/2024) Original Instructions Instructions for Replacing the TQ-125™ Engine Control with an L-Series 8404-7104 Speed Controller...
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Revisions—Changes in this publication since the last revision are indicated by a black line alongside the text. Woodward reserves the right to update any portion of this publication at any time. Information provided by Woodward is believed to be correct and reliable. However, no responsibility is assumed by Woodward unless otherwise expressly undertaken.
Released Application Note 51272 Replacement of TQ-125 with L-Series Control Warnings and Notices Important Definitions This is the safety alert symbol. It is used to alert you to potential personal injury hazards. Obey all safety messages that follow this symbol to avoid possible injury or death.
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Start-up On- and off-highway Mobile Applications: Unless Woodward's control functions as the supervisory control, customer should install a system totally independent of the prime mover control system that...
Do not touch the components or conductors on a printed circuit board with your hands or with conductive devices. To prevent damage to electronic components caused by improper handling, read and observe the precautions in Woodward manual 82715 , Guide for Handling and Protection of Electronic Controls, Printed Circuit Boards, and Modules.
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TQ-125 control and lever arm but not the linkage. The L-Series control will be mounted on an adapter plate which is designed to mount to the same bracket that held the TQ-125. A new lever arm is installed to the L-Series assembly and connected to the linkage. The L-Series electrical harness is installed using the existing wiring for the TQ-125.
The TQ-125 control should be rigidly mounted to the engine with a bracket. At the minimum fuel position, remove the linkage from the TQ-125 by loosening the lever-retaining bolt. Remove the four 0.250-28 screws which attach the TQ-125 to the bracket and remove the control.
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Released Application Note 51272 Replacement of TQ-125 with L-Series Control Figure 2. Linkage Once installed, manually stroke the fuel-control linkage from stop to stop as if the actuator were moving it. The linkage must move freely, without friction and backlash. Lubricate or replace worn linkage or fuel control parts as required.
1. Using the harness provided in the installation kit (8923-1163), replace the TQ-125 connector by wiring in the L-Series connector into the TQ-125 portion of the engine harness as shown in the diagrams.
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Replacement of TQ-125 with L-Series Control If replacing a TQ-125 8405-214 using an ignition input from the coil (–) for a speed signal, it will be necessary to relocate the orange wire from PIN 11 on the L-Series connector, to PIN 12 as shown below.
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Released Application Note 51272 Replacement of TQ-125 with L-Series Control TQ-125 8405-206, 207, 208 & 212 Dynamics Select Run/Stop +12 to +24 VDC L-Series 8404-7104 +12 to +24 VDC AUX2 Run/Stop AUX1 Dynamics Select Figure 6. Wiring Pinout (TQ 8405-206, 207, 208, 212) If using an ignition input for the speed signal input, relocate the ORANGE wire from PIN 11 (MPU) to PIN 12 (IGN).
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Released Application Note 51272 Replacement of TQ-125 with L-Series Control Configuring the L-Series You must configure the L-Series using the Software Service Tool. Parameters such as Speed Input, Rated Setpoint, and Overspeed Threshold will need to be configured before starting the engine. Refer to L-series Speed Control Manual 26250 for a complete description of all L-Series features and programming examples.
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Position calibration is normally used when full travel of the actuator is constrained or limited such that 0 to 60 degrees of travel is not used. When replacing a TQ-125 with an L-Series, the linkage travel is usually less than 60 degrees, and a position calibration must be performed for proper operation.
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Released Application Note 51272 Replacement of TQ-125 with L-Series Control The minimum position and the failed direction are listed here and graphically shown from the shaft end of the L-Series. If this is not correct, use the pulldown arrow the change the direction of rotation and the failed direction to the correct orientation for your installation.
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Released Application Note 51272 Replacement of TQ-125 with L-Series Control When complete, the following screen will appear. You must cycle power in order to save the new min/max stop positions. Select the Finish button and immediately remove power from the L-Series for approximately 5 seconds, then re-apply power.
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Released Application Note 51272 Replacement of TQ-125 with L-Series Control Select the checkbox to enable manual position tuning. Note the minimum and maximum positions at the bottom of the screen—these are the saved minimum and maximum positions from your calibration. For best results, you should have a minimum 30 degrees of travel—anything less than 30 degrees may cause instability or difficulty in tuning the dynamic settings due to excessive gain in the mechanical linkage.
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Released Application Note 51272 Replacement of TQ-125 with L-Series Control Configuration File Control Tab Settings RPM where engine cranking is detected. “Crank RPM” Percent of output (valve position) when crank RPM is detected. RPM where Speed control takes over. (Not Rated Speed!) Should be above 500 RPM for gaseous engines.
Released Application Note 51272 Replacement of TQ-125 with L-Series Control Revision History Changes in Revision C— • Updated Part Number of L-Series Speed Controller to 8401-7104 Woodward...
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Email and Website—www.woodward.com Woodward has company-owned plants, subsidiaries, and branches, as well as authorized distributors and other authorized service and sales facilities throughout the world. Complete address / phone / fax / email information for all locations is available on our website.
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