1. Introduction
The SHANGSIMOUDLECX YH-800 Sensor Tester is a portable device designed for efficient and reliable testing of various DC sensors. It supports two-, three-, and four-wire sensors with both PNP and NPN outputs. This manual provides essential information for the safe and effective use of your YH-800 Sensor Tester, covering setup, operation, and maintenance.
2. Safety Information
Important Safety Information:
Read all instructions before use. Failure to follow these instructions may result in damage to the product or personal injury.
- Keep the device and its cord out of reach of children under 3 years old.
- Keep away from children unless supervised by an adult.
- Do not use this product for purposes other than its intended use.
- Inspect the product before each use; do not use if damaged.
- Follow installation and operation guidelines to avoid injury.
- Do not expose to water or moisture.
3. Product Overview
The YH-800 Sensor Tester is a versatile tool for quickly verifying the functionality of various industrial sensors. It helps users confidently check sensor operation, avoiding unnecessary replacements and enhancing fault-finding capabilities in automation and control systems.
It is capable of testing the following sensor types:
- Inductive (metal induction)
- Capacitive
- Optoelectronic
- Magnetic
- Ultrasonic

This image shows the front of the YH-800 tester, highlighting the output terminals (Positive, Negative), and indicator lights for low battery (red), switch connection (green), PNP mode output (yellow), and NPN mode output (yellow).
4. Specifications
| Feature | Detail |
|---|---|
| Model | YH-800 |
| Compatible Sensor Types | Two-, three-, or four-wire DC sensors (PNP/NPN outputs) |
| Testable Sensor Technologies | Inductive, Capacitive, Optoelectronic, Magnetic, Ultrasonic |
| Application | Optoelectronic/Proximity/Magnetic/Fiber Amplifier |
| Color | Black |
| Material | Plastic |
| Size (L x W x H) | 93 x 60 x 23 mm |
| Power Source | 2 x 6F22 9V batteries (not included) |
| Weight | Approximately 0.05 kg |
| Origin | Mainland China |
5. Setup
5.1 Battery Installation
- Locate the battery compartment on the back of the YH-800 tester.
- Open the battery compartment cover.
- Insert two 6F22 9V batteries, ensuring correct polarity (+/-).
- Close the battery compartment cover securely.
Note: Batteries are not included with the tester.
5.2 Sensor Connection
The YH-800 tester features output terminals for connecting sensors. Ensure the tester is powered off before connecting any sensors.

This image illustrates how to connect both three-wire and two-wire sensors to the YH-800 tester. For three-wire sensors, connect Brown to positive, Black to output, and Blue to negative. For two-wire sensors, connect Brown to positive and Blue to negative.
Follow these general guidelines for wiring:
- Three-wire sensor:
- Connect the Brown wire to the Positive (+) terminal.
- Connect the Black wire to the Output terminal.
- Connect the Blue wire to the Negative (-) terminal.
- Two-wire sensor:
- Connect the Brown wire to the Positive (+) terminal.
- Connect the Blue wire to the Negative (-) terminal.
Caution: Always ensure correct wiring to prevent damage to the tester or sensor.
6. Operating Instructions
Once the batteries are installed and the sensor is connected, you can begin testing.
- Power On: Turn on the tester using the power switch (if available, otherwise it's always on when batteries are inserted).
- Observe Indicators:
- If the red light labeled '%' (percentage) is on, the battery is low and needs replacement.
- When the sensor switch is activated (e.g., by detecting an object), the green light will illuminate, indicating the switch is connected and functioning.
- For PNP mode output, a yellow light labeled 'PNP' will illuminate.
- For NPN mode output, a yellow light labeled 'NPN' will illuminate.
- Test Sensor Functionality: Activate the sensor by bringing an appropriate object within its detection range. Observe the green light for switch connection and the relevant yellow light (PNP or NPN) for output mode confirmation.
- Power Off: After testing, disconnect the sensor and turn off the tester to conserve battery life.
7. Troubleshooting
| Problem | Possible Cause | Solution |
|---|---|---|
| Tester does not power on / Red '%' light is on | Low or depleted batteries. | Replace both 6F22 9V batteries. |
| Green light does not illuminate when sensor is activated | Sensor not properly connected, faulty sensor, or incorrect sensor type for tester. | Check sensor wiring (refer to Figure 2). Ensure the sensor is functional and compatible with the tester. |
| PNP/NPN yellow light does not illuminate | Sensor output not active, incorrect sensor type, or faulty sensor. | Verify sensor activation. Confirm the sensor's output type (PNP/NPN) matches the expected behavior. Test with a known good sensor if possible. |
| Inconsistent readings | Loose connections, interference, or sensor malfunction. | Ensure all connections are secure. Test in an environment free from strong electromagnetic interference. Consider testing the sensor in its intended application or replacing it. |
8. User Tips
- Always keep spare 9V batteries on hand for uninterrupted testing.
- When testing different sensor types, ensure you understand their specific activation methods (e.g., metal for inductive, proximity for capacitive).
- For quick checks, simply observing the green 'switch connected' light can confirm basic sensor functionality.
9. Maintenance
- Cleaning: Wipe the tester with a soft, dry cloth. Do not use abrasive cleaners or solvents.
- Storage: Store the device in a cool, dry place away from direct sunlight and extreme temperatures.
- Battery Care: Remove batteries if the tester will not be used for an extended period to prevent leakage and damage.
10. Warranty and Support
For warranty information or technical support, please contact the manufacturer or your point of purchase. Keep your purchase receipt as proof of purchase.
A detailed user manual is available in PDF format: View User Manual (PDF)
11. Compliance Information
This product is manufactured and distributed in compliance with relevant regulations.
- Manufacturer: Shenzhen ShangLe Network Technology Co., Ltd
- EU Authorized Representative: Shenzhen ShangLe Network Technology Co., Ltd
- Importer: Shenzhen ShangLe Network Technology Co., Ltd
- Electrical Safety: This product relates to electrical safety for electrical or electronic products.