High voltage relay
R81A Series
R81A series high voltage relays are designed to meet demanding load requirements. Available in a variety of compact form factors, this relay utilizes a high dielectric encapsulant to provide superior external isolation. The RF-rated design ensures exceptional performance in applications requiring precise switching and reliable isolation up to 7 kV. Equipped with tungsten contacts, the R81A delivers enhanced make and break load switching capabilities and can continuously carry 5 or 10 amps, depending on the termination type. Common applications include antenna tuning units (ATUs) and high voltage test equipment. Featuring a Single Pole Single Throw, Normally Open (SPST-NO) configuration, this relay offers a simple yet effective solution for isolation, utilizing a single stationary contact to maintain isolation until coil power is applied.
Key specifications
R81A Series at a glance
- Voltage
- 7 kV
- Current
- 5 A or 10 A
- Contact form
- SPST-NO
- Dielectric
- Vacuum
| Voltage rating | 7 kV |
|---|---|
| Current rating (continuous, DC or 60 Hz) | 5 A or 10 A |
| Contact arrangement | SPST-NO |
| Contact form | A = Normally Open |
| Operation | Make/Break Load Switching |
| Coil voltage | 12 or 26.5 VDC |
| Construction | Stacked ceramic |
| Dielectric | Vacuum |
| Contact material | Molybdenum/Tungsten |
| HV termination | PCB Pins (5 A max), PCB Pins (10 A max), Flying Leads or Threaded Terminals |
| Coil termination | PCB Pins or Threaded Terminals |
| Mounting | PCB or Panel Mount |
Datasheet
Full ratings, dimensions and drawings are in the R81A Series datasheet (PDF).
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Datasheet specifications
R81A Series performance
| Contact Arrangement | Form A, SPST-NO or Form B, SPST-NC |
|---|---|
| Max Operating Voltage (Peak, between Contacts and Contacts to Base) (Max Leakage Current: 15µA) | 7 kV dc or 60 Hz |
| Test Voltage (Peak, between Contacts and Contacts to Base) (Max Leakage Current: 15µA) | 8 kV dc or 60 Hz |
| Continuous Current, Max | 5 A 2X .025 [0.64 mm] PCB Mount Version Only; 10 A 2X .065 [1.62 mm] PCB Mount Version Only; 10 A Panel Mount and Flying Lead Versions Only |
| Contact Resistance (Max) | 0.030 Ω @ 1 A |
| Operate Time (Max, incl bounce) | 10 ms |
| Release Time (Max) | 10 ms |
| Shock - Functional, 1/2 Sine, 11 ms | 30 G |
| Vibration, Operating, Sine (50-2,000 Hz) Peak | 10 G |
| Operating Temperature | -50°C to 85°C |
| Ingress Protection | Hermetic, exceeds IP67 and IP6K9 |
| Mechanical life | 2,000,000 cycles |
| Weight | 56 g |
| Coil (25 °C) | 12 VDC | 26.5 VDC |
|---|---|---|
| Nominal Voltage | 12 VDC | 26.5 VDC |
| Pick-up Voltage, Max | 8 VDC | 16 VDC |
| Drop-out Voltage | 0.5-5 VDC | 1-10 VDC |
| Coil Resistance | 70 Ω | 290 Ω |
From the R81A datasheet. The datasheet notes on coil temperature effects apply. Download the datasheet.
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Applications
Where the R81A Series is used
High Power Test Systems and Load Banks
Switching and protection for load banks, dynos, and high-power test setups.
Medical Devices and Therapy Systems
High voltage switching for medical diagnostic, therapy, and specialty equipment.
Scientific and Analytical Instrumentation
HV switching for scientific instruments, measurement systems, and laboratory setups.
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Questions about the R81A Series?
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