Medical Imaging Equipment: Why High Voltage Reed Relays Are Essential for CT and X-Ray Systems
CT scanners and X-ray equipment operate in high-voltage environments ranging from 80kV to 150kV, requiring precise control of X-ray tube switching. These devices impose stringent requirements on switching components:
- High Insulation Resistance: Must withstand thousands of volts of transient voltage
- Extremely Low Leakage Current: Ensuring patient safety
- Long Mechanical Life: Medical equipment demands high reliability
- Zero Contact Bounce: Avoiding image artifacts
Advantages of High Voltage Reed Relays
1. Superior Insulation Performance
SHR’s HVR series high voltage reed relays use vacuum-sealed reed switches, where the contact gap provides excellent insulation in vacuum:
| Model | Breakdown Voltage | Load Current | Typical Application |
|---|---|---|---|
| HVR-4KV | 4,000V DC | 0.5A | X-ray control circuits |
| HVR-10KV | 10,000V DC | 1A | CT high voltage switching |
| HVR-15KV | 15,000V DC | 1A | High-energy X-ray equipment |
| HVR-20KV | 20,000V DC | 2A | Industrial CT systems |
2. Zero Contact Bounce
Unlike electromagnetic relays, reed relay contacts operate inside a sealed glass tube, unaffected by external vibration. This is particularly important for mobile medical equipment.
3. Long Life Design
The HVR series uses ruthenium alloy contact material, achieving mechanical life up to 10⁹ operations, meeting the 10+ year service life requirements of medical equipment.
Application Case Study: CT Scanner High Voltage Control
A leading medical equipment manufacturer adopted HVR-10KV relays in their 128-slice CT scanner to control the X-ray tube high voltage circuit:
- Operating Voltage: 80-140kV (via transformer step-up)
- Control Circuit Voltage: 5kV DC
- Switching Frequency: ~1000 operations per scan
- Annual Operations: ~5 million
Why HVR-10KV was chosen:
- 10kV breakdown voltage provides adequate safety margin
- Vacuum sealing ensures long-term stability
- Compact size for easy PCB mounting
Selection Guide
When selecting high voltage reed relays for medical imaging equipment, consider:
- Voltage Rating: Choose 2-3x safety margin above operating voltage
- Load Type: Capacitive loads require surge current consideration
- Mounting Method: PCB or socket mounting
- Certification Requirements: Medical equipment typically requires UL/CE certification
SHR Solutions
SHR AUTOSENSOR offers a complete line of high voltage reed relays designed for medical, industrial, and research applications:
- HVR Series: 4-20kV, standard package
- HVFR Series: 4-10kV, compact package
- HRX Series: 10-18kV, ultra-high voltage applications
All products are ISO 9001 certified and support custom designs.
Contact us for technical support:
- 📧 [email protected]
- 📱 WhatsApp: +86 13761571029
- 🌐 www.reed-relay.com