Generic Chinese (Ditron Compatible) Scale Pinouts
This pinout covers approximately 99% of Chinese glass scales and many magnetic scales. It's the most common standard used by manufacturers like Ditron, Easson, and countless generic suppliers.
Standard 9-Pin D-Sub Connector
The overwhelming majority of Chinese scales use this pinout:
| Pin | Signal | Description | Voltage |
|---|---|---|---|
| 1 | +5V | Power supply positive | +5V DC |
| 2 | 0V | Power supply ground | 0V |
| 3 | A | Phase A signal | 0-5V TTL |
| 4 | /A | Phase A inverted (if differential) | 0-5V TTL |
| 5 | B | Phase B signal | 0-5V TTL |
| 6 | /B | Phase B inverted (if differential) | 0-5V TTL |
| 7 | Z | Index/reference pulse (if present) | 0-5V TTL |
| 8 | /Z | Index inverted (if differential) | 0-5V TTL |
| 9 | Shield | Cable shield/case ground | Ground |
Signal Types
Single-Ended (Most Common)
Most Chinese scales use single-ended TTL signals:
- Use pins 3 (A) and 5 (B) only
- Pins 4, 6, 8 may be unused or tied to ground
- Simple 0-5V square wave outputs
- Works well for cable runs under 3 meters
Differential (Less Common)
Some higher-quality Chinese scales provide differential outputs:
- Use both normal and inverted signals
- Better noise immunity
- Suitable for longer cable runs
- More expensive but more reliable
Common Variations
15-Pin D-Sub (Rare)
Some scales use 15-pin connectors but follow the same basic pinout:
- Pins 1-9 typically match the 9-pin standard
- Additional pins may be unused or for special functions
- Always verify with multimeter before connecting
Different Connector Types
While the electrical pinout is standard, connector types vary:
- 9-pin D-sub (most common)
- 15-pin D-sub
- Circular connectors (industrial applications)
- Flying leads (no connector)
Compatible Brands
This pinout works with scales from:
- Ditron: DG series glass scales
- Easson: GS series scales
- Generic Chinese: Most eBay/AliExpress scales
- Sino: Many models
- Aikron: Standard models
- Many others: Most Chinese manufacturers follow this standard
TouchDRO Compatibility
All TouchDRO adapters support this pinout:
- TDA-4xx series: Full support, auto-detection
- DIY glass scale kits: Designed specifically for this pinout
- DIY adapters: Standard configuration
Wiring to TouchDRO Adapters
TDA-4xx Series
- Connect directly using appropriate cable
- Adapter auto-detects signal type
- Supports both single-ended and differential
DIY Glass Scale Adapter
- Pin 1 (+5V) → Adapter +5V
- Pin 2 (0V) → Adapter GND
- Pin 3 (A) → Adapter A input
- Pin 5 (B) → Adapter B input
- Pin 9 (Shield) → Adapter case/shield
Verification Steps
Before connecting to TouchDRO:
- Power check: Verify +5V between pins 1 and 2
- Signal check: Move scale and verify A/B signals toggle
- Phase check: Ensure A and B are 90° out of phase
- Direction check: Verify signal sequence for direction
Troubleshooting
- No power: Check +5V supply, verify pinout
- No signals: Scale may be damaged or different pinout
- Wrong direction: Swap A and B connections
- Erratic readings: Check cable integrity and shielding
Cable Considerations
- Use shielded cable for runs over 1 meter
- Keep cable length under 10 meters when possible
- Avoid running near power cables or motors
- Connect shield at adapter end only