Sensata Gigavac G81AB57

Sensata Gigavac G81AB57 is a 10kV SPST-NO High Voltage Relay from the G81A series, designed for high-voltage test systems, source switching, instrumentation circuits, and specialized power control equipment. This High Voltage Relay provides a normally open contact form, 5A contact rating, 26.5VDC coil, tungsten contacts, stud terminals, and panel or chassis mounting. It is a relay for controlled high-voltage on/off switching, not a high-current battery contactor.

The G81A platform is useful when a system needs strong voltage isolation and reliable switching in a compact package. G81AB57 supports switching up to 10000VAC or 10000VDC maximum according to distributor data. Its tungsten contact material is suitable for demanding high-voltage switching conditions, while the 10ms operate and release timing supports controlled sequencing in test fixtures, laboratory instruments, and high-voltage control panels.

Product Positioning

G81AB57 should be positioned as a normally open High Voltage Relay for 10kV-class switching. It is different from the G43C332 relay because G43C332 uses an SPDT transfer contact, while G81AB57 uses a simpler SPST-NO contact. This makes G81AB57 appropriate when the circuit only needs to open or close one high-voltage path rather than transfer between two paths.

This High Voltage Relay is also different from GV, HX, or P Series DC contactors. Those products are usually selected for battery isolation or high-current DC power paths. G81AB57 is focused on high-voltage relay applications where the current level is lower, the voltage stress is high, and compact relay-style switching is required.

Key Specifications

• Manufacturer series: Sensata Gigavac G81A
• Part number: G81AB57
• Product type: High Voltage Relay
• Contact form: SPST-NO, 1 Form A
• Contact rating: 5A
• Maximum switching voltage: 10000VAC / 10000VDC
• Coil voltage: 26.5VDC
• Coil current: approximately 91.4mA according to distributor data
• Coil power: approximately 2.4W according to distributor data
• Coil resistance: approximately 290 ohms according to distributor data
• Contact material: tungsten
• Termination style: stud terminals
• Mounting type: chassis mount / panel mount
• Typical operate time: approximately 10ms
• Typical release time: approximately 10ms
• Operating temperature range: -55°C to +85°C

Features and Benefits

The main benefit of G81AB57 is its 10kV switching capability in a simple normally open relay configuration. A normally open High Voltage Relay keeps the circuit open when the coil is not energized and closes the circuit only when the controller applies coil power. This behavior is useful for test equipment, power supply outputs, controlled HV enable paths, and source connection circuits.

The SPST-NO contact form keeps the circuit architecture straightforward. If the design only needs one controlled high-voltage path, G81AB57 can be easier to apply than an SPDT transfer relay. The High Voltage Relay can be used to enable a high-voltage output, connect a load, isolate a test channel, or control a measurement path without adding an unused transfer contact.

The 26.5VDC coil configuration is common in specialized industrial, aerospace-style, and high-reliability control systems. Designers should match the relay driver to the coil voltage, coil current, must-operate voltage, and release behavior. Distributor data lists a 16VDC must-operate voltage and 1VDC must-release voltage, which should be considered during driver design.

Tungsten contacts and stud termination support robust high-voltage switching. The High Voltage Relay is suitable for assemblies where reliable contact material, secure terminal connections, and compact panel mounting are important. Its -55°C to +85°C operating temperature range also supports use in demanding industrial and test environments.

Applications

G81AB57 is especially suitable for high-voltage test and measurement equipment. In a hipot tester, insulation test instrument, laboratory power supply, or automated test fixture, this High Voltage Relay can connect or isolate a high-voltage output under controller command. The 10kV rating makes it relevant to systems that exceed the capability of ordinary relays.

The relay can also be used in source selection panels, capacitor charging controls, HV enable circuits, electrostatic equipment, cable test systems, and industrial instrumentation. Because it is SPST-NO, G81AB57 is best used for simple on/off high-voltage switching rather than transfer routing. If the circuit must switch one common node between two paths, an SPDT relay such as a G43C-type model may be more suitable.

For compact control panels, G81AB57 offers a focused High Voltage Relay option with stud terminals and panel mounting. The final application should be reviewed for voltage, current, hot-switching conditions, insulation spacing, duty cycle, altitude, contamination level, and applicable safety standards.

Selection Guide

Before selecting G81AB57, confirm that the application requires a normally open SPST High Voltage Relay. If the circuit should remain open when control power is removed, SPST-NO is appropriate. If the circuit needs a default closed path, an SPST-NC model should be reviewed. If the circuit requires transfer switching, an SPDT relay is the better configuration.

Engineers should verify maximum voltage, load current, hot switching current, load type, switching frequency, and required isolation distance. Although G81AB57 is listed for up to 10kV AC/DC and 5A contact rating, real application limits can depend on waveform, circuit energy, wiring layout, enclosure condition, and safety margin.

The coil driver should be designed around the 26.5VDC coil. Check available control voltage, driver current capacity, coil suppression needs, and release behavior. Mechanical integration should also consider stud terminal access, panel mounting, creepage and clearance, and serviceability.

FAQ

What is G81AB57 used for?

G81AB57 is used for high-voltage test systems, instrumentation switching, source enable circuits, power supply control, and simple 10kV-class on/off switching.

Is G81AB57 a High Voltage Relay?

Yes. G81AB57 is a Sensata Gigavac G81A series High Voltage Relay with SPST-NO contact form and 10kV AC/DC switching capability.

What coil voltage does G81AB57 use?

G81AB57 uses a 26.5VDC coil. Distributor data lists approximately 91.4mA coil current and 2.4W coil power.

Is G81AB57 normally open?

Yes. G81AB57 is an SPST-NO relay, so the contact path is open when the coil is not energized and closes when the coil is powered.

How is G81AB57 different from G43C332?

G81AB57 is an SPST-NO High Voltage Relay for one controlled on/off path, while G43C332 is an SPDT High Voltage Relay for transfer switching between two paths.

Conclusion

G81AB57 is a 10kV SPST-NO High Voltage Relay for test equipment, instrumentation, source switching, and specialized high-voltage control systems. With its Sensata Gigavac G81A design, 5A contact rating, 26.5VDC coil, tungsten contacts, stud terminals, panel mounting, and fast 10ms switching behavior, it is a practical relay option for applications that need reliable high-voltage on/off control rather than high-current DC contactor switching.