1. Introduction
The GCS909 2-Axis LCD Digital Readout (DRO) Kit is a versatile and user-friendly precision measurement system designed for various machine tools, including lathes, milling machines, grinders, wire-cutting machines, and drilling machines. This manual provides detailed instructions for the proper installation, operation, and maintenance of your GCS909 DRO system.
The GCS909-2 model features a multi-language interface, supporting 19 languages for global usability. Its large LCD display ensures clear and easy readability of measurements during operation.

2. Product Components
Depending on your selected configuration, your GCS909 DRO Kit may include the following:
- GCS909-2 LCD DRO Display: One unit, including power cable, user manual, mounting arm, screw bag, and display protector.
- Linear Scales (Optional, included in "SET" configurations):
- Two linear scales (either 0.005mm or 0.001mm accuracy) with covers, mounting brackets, and screw bags.
- Important: For "SET" configurations, please specify the required travel length of the linear scales at the time of purchase. Failure to do so may result in delays or incorrect delivery.
- Accessories: Display cover, linear scale dust cover, mounting bracket, connection plate, mounting screws, user manual.

3. Setup and Installation
3.1 Physical Installation of DRO Display
- Attach the mounting arm to the back of the GCS909-2 display using the provided screws.
- Secure the mounting arm to a stable surface near your machine tool, ensuring the display is easily visible and accessible.
- Connect the power cable to the display unit and a suitable AC power outlet (AC 80-250V, 50/60Hz).

3.2 Linear Scale Installation
Install the linear scales on the machine tool axes (X, Y, Z if applicable) according to your machine's requirements. Ensure the scales are parallel to the axis of motion and the readhead moves smoothly along the scale.
- Mount the linear scale body securely to the machine bed or moving part.
- Attach the readhead to the opposing moving part, ensuring proper alignment with the scale.
- Use the provided mounting brackets and screws for secure installation.
- Ensure the scale covers are properly installed to protect the grating ruler from dust and debris.


3.3 Electrical Connection of Linear Scales
Connect the linear scales to the corresponding DB9 ports on the back of the GCS909-2 display. The system accepts TTL square wave signals. If you require EIA-442 signals, please ensure this was specified at the time of order.

Note: TTL output signal is sent by default. If you need RS422 signal, please contact us.
3.4 Power On and Initial Setup
- Ensure all connections are secure.
- Turn on the power switch on the DRO display.
- The display will boot up. You may need to enter a system password (default: 2008) to access system parameter settings.
- Language Selection: Navigate to "System parameter Settings" and locate the "Language" option. Use the F3/F4 keys to cycle through the 19 available languages (English, Russian, German, French, Spanish, Portuguese, Italian, Polish, Ukrainian, Croatian, Slovak, Dutch, Czech, Turkish, Japanese, Korean, Vietnamese, Simplified Chinese, Traditional Chinese) and select your preferred language.
- Set the appropriate resolution (10 micron, 5 micron, 2 micron, 1 micron, 0.5 micron) for your linear scales in the system settings.
4. Operating Instructions
4.1 Basic Functions
- Zeroing: Set the current position to zero for any axis.
- Preset Data: Input a specific value to an axis.
- Unit Toggle: Switch between millimeter (mm) and inch (inch) display units.
- Absolute/Incremental/SDM: Toggle between absolute, incremental, and 200 groups of datum memory (SDM) modes.
- 1/2 Function: Quickly find the center point between two measured points.
- Clear All SDM Datum: Erase all stored datum points.
- Screen Saver: Activates after a set period of inactivity to protect the display.
- Power Interruption Memory: Retains current position data in case of power loss.
- Linear Compensation: Corrects for linear errors in the machine or scale.
- Non-Linear Error Compensation: Corrects for non-linear errors.
- Anti-shake Function: Stabilizes readings in vibrating environments.
- R/D Function: Toggles between radius and diameter display for turning applications.
- Coordinate Joint Function: Combines axes for specific operations.
- Factory Reset: Restores all settings to their default values.
- Setup Location Display Method: Configures how coordinates are displayed.
- Signal Interface Type: Configures the input signal type (TTL/EIA-442).
- Setup the Resolution: Adjusts the display resolution to match the linear scales.
- Setup Positive Direction for Counter: Defines the positive direction of movement for each axis.
- Setup Compensation Type: Selects the type of compensation applied.
- Setup Encoder Linear: Configures encoder linearity.
- Setup Screw Clearance: Compensates for backlash in lead screws.
- Setup Coordinate Joint: Defines how axes are linked.
- Setup INCH Unit Dot: Configures decimal point display for inch units.
- Setup the Anti-Filtering: Adjusts signal filtering.
- Setup the Angle Display Mode: Configures how angles are displayed.
- Setup Screen Saver Time: Sets the duration before the screen saver activates.
- Setup Language: Selects the display language.
- Setup Anti-shake: Configures anti-shake sensitivity.
- Setup RS 485 Baudrate, MODBUS_RTU: Configures serial communication parameters.
- Brightness Adjustment: Adjusts display brightness.
- Calculator: Built-in calculator for quick calculations.
- Help: Accesses the internal manual for guidance.
- 200 Groups SDM Coordinate: Stores and recalls up to 200 datum points.
- Zeroing at the Current Point: Sets the current position as the new zero.
- Preset Datum of SDM Coordinate: Sets a specific value for a stored datum point.
4.2 Special Functions
The GCS909-2 DRO offers advanced functions for complex machining operations:
- Circumference Holes Processing (PCD): For drilling holes on a bolt circle diameter.
- Linear Holes Processing: For drilling a series of holes along a straight line.
- Smooth ARC Processing: For machining smooth arcs.
- Simple ARC Processing: For basic arc machining.
- Slope Processing: For machining angled surfaces.
- Network Holes Processing: For creating a grid of holes.
- Rectangle Inner Processing: For machining rectangular pockets.
- EDM Processing: Specific functions for Electrical Discharge Machining.

5. Maintenance
- Cleaning: Regularly clean the DRO display and linear scales with a soft, dry cloth. Avoid using harsh chemicals or abrasive materials.
- Environmental Protection: Keep the DRO system away from excessive dust, moisture, and direct sunlight. Ensure proper ventilation to prevent overheating.
- Cable Inspection: Periodically check all cables for signs of wear, damage, or loose connections.
- Linear Scale Protection: Ensure the linear scale dust covers are always in place to protect the internal grating from contaminants.
6. Troubleshooting
- No Display/Power:
- Check if the power cable is securely connected to both the DRO and the power outlet.
- Verify that the power switch on the DRO is in the "ON" position.
- Ensure the power outlet is functional.
- Incorrect Readings/No Movement on Display:
- Check if the linear scale cables are securely connected to the correct DB9 ports on the DRO.
- Inspect the linear scales and readheads for any physical obstructions or damage.
- Verify that the resolution setting in the DRO matches the resolution of your linear scales.
- Ensure the linear scales are clean and free from debris.
- Language Issues: If the display language is incorrect, refer to Section 3.4 "Power On and Initial Setup" for instructions on changing the language.
- System Errors: If the DRO displays an error message, consult the "Help" function within the DRO's menu or refer to the detailed user manual provided with the product.
7. Specifications
| Feature | Specification |
|---|---|
| Brand Name | GCSHXX |
| Model Number | GCS909 |
| Certification | CE |
| Origin | Mainland China |
| Supported Languages | 19 Multi-Language LCD DRO (English, Russian, German, French, Spanish, Portuguese, Italian, Polish, Ukrainian, Croatian, Slovak, Dutch, Czech, Turkish, Japanese, Korean, Vietnamese, Simplified Chinese, Traditional Chinese) |
| Digital Readout (DRO) Type | 2 Axis LCD DRO Set |
| Input Voltage | AC80-250V 50/60HZ |
| Application | DRO system is used for mill/lathe/drilling/cutting machines etc |
| Scale Available Travel Length | 50mm-1000mm |
| Scale Available Total Length | Travel Length + 138mm |
| Scale Resolution | 5um (0.005mm), 1um (0.001mm) |
| Cable Length | 3 meters (longer available) |
| Output Signal | TTL (EIA-442 optional) |
| Battery Included | No |
| High-concerned chemical | None |
8. Warranty and Support
The GCS909 DRO Kit comes with a 2-year warranty from the date of purchase, covering manufacturing defects and malfunctions under normal use.
For technical support, inquiries, or warranty claims, please contact your vendor or the manufacturer directly. Ensure you have your purchase details and product model number available.
Returns: If you need to return an item for any reason, please contact your seller within 15 days of receipt to arrange the return. Ensure the product is in its original condition. The buyer is responsible for return shipping costs.
9. User Tips
- Specify Scale Length: When ordering a complete DRO kit with linear scales, always clearly communicate the desired travel length or total length of the scales to the seller. This prevents delays and ensures you receive the correct components for your machine.
- Check All Components: Upon receiving your order, carefully check all included components against the product description to ensure everything is present and undamaged.
- Consult the Manual: The DRO display has a built-in "Help" function. Utilize this feature for quick access to instructions and parameter explanations during operation.