1.Question – What are Vacuum Feedthroughs?

Answer– Vacuum Feedthroughs are hermetic, vacuum sealed components and assemblies that have a conductor (wire, pins or solid rod) mounted into a ceramic to metal, glass to ceramic insulator joint to electrically isolate the current carrying conductors from the metallic mounting. They are suitable for high vacuum (HV) and ultra-high vacuum (UHV) environments and temperatures ranging from -270°C to 450°C.

Vacuum Feedthroughs are used to transport a signal, electrical current, temperature measurement or fibre optic into/from a Vacuum Vessel. Vacuum Feedthroughs are supplied in weldable or flanged configurations. They are defined by the requirements of the intended use, installation, insulation, and conductor material.

2.Question– What types of Vacuum Feedthroughs are available?

Answer-Vacuum Services Ltd. stock a variety of Vacuum Feedthroughs in a number of configurations and power requirements such as-

  • Power Feedthroughs
  • Multi-pin feedthroughs
  • Co-axial Feedthroughs
  • Thermocouple Feedthroughs
  • Instrument Feedthroughs

3.Question- What are Vacuum Power Feedthroughs?

Answer– Vacuum Power Feedthroughs provide transportation of electrical current into/from a High-Vacuum (HV) or Ultra-high Vacuum (UHV) Vacuum Vessel.

Vacuum Power Feedthroughs are available in a vast variety of types of mounting flanges, voltages, and current carrying capacities.


Electrical Power Feedthroughs are available in the Voltage & Current range 1-kV 3 A to 8 kV 500 A

4.Question– What are Multi-pin Vacuum Feedthroughs?

Answer– Multi-pin Vacuum Feedthroughs are feedthroughs with two or more conducting pins and are designed to accept a plug on the air side, but some feedthroughs allow for plugs on the vacuum side also. Multi-pin Vacuum Feedthroughs are available in a vast variety of types of mounting flanges and pin design
Hermetically sealed Multi-pin Vacuum Feedthroughs are designed primarily to provide instrumentation signals, voltage and/or current into/from a High-Vacuum (HV) or Ultra-high Vacuum (UHV) Vacuum Vessel.

Voltages up to 12 kV DC

  • Currents up to 40 A
  • Temperature range from -269°C to 450°C
  • Internal pressure 1×10-10 mbar up to 41 bar (600 psig)
  • Up to 50 pins/conductors

5.Question – What are Co-axial Vacuum Feedthroughs?

Answer – Co-axial Vacuum Feedthroughs are connectors that consist of two concentric conductors, a central inner conductor serves as a current carrying contact and is surrounded by and insulated from an outer tubular conductor that serves as an electromagnetic shield. The outside conductor is usually at ground potential but in some product variations may be floated off ground by employing an additional insulating ring. The outer conducting surface can prevent radio frequency noise from passing to or from the central conductor.

Co-axial Vacuum Feedthroughs are available in Industry Standard types BNC, MHV, various SHVs, N, Microdot, SMA, and SMB. (see images for some types)

Industry Standard Specifications

  • Grounded shield or floating shield configuration
  • High frequency 50 ? impedance matched connectors as SMA, BNC, Type N and HN
  • Connectors are sold with or without air side plugs

6.Question – What are Thermocouple Vacuum Feedthroughs?

Answer- Thermocouple Vacuum Feedthroughs are used to measure temperature inside a Vacuum Vessel. Thermocouple Vacuum Feedthroughs are manufactured with differing thermocouple materials or compensating material. The differing materials transmit electromotive force (EMF) generated by the heat application to the thermocouple hot junction (bead joint) transmitted from the inside of a Vacuum Vessel. External temperature measurement controllers evaluate the strength of the electromotive force that is proportional to the temperature at the hot junction and displays the temperature. (see images for some types)

Typical ANSI-standardized thermocouple material pairs are listed in the table below.


Typical ANSI-standardized thermocouple material pairs are listed in the table below.

7.Question – What are Instrument Vacuum Feedthroughs?

Answer – Instrument Vacuum Feedthroughs are designed to transfer low current, low or high voltage signals from low or high impedance into/from a Vacuum Vessel. They have one or multiple conductors (wire) with a standard electrical plug/socket on the air-side. Some types are also suitable to have connections on the vacuum side. (see images for some types)


Please Note: Vacuum Services Ltd do not have a minimum order quantity, if your needs are for a 1 off flange, centering, gasket or clamp and we receive an order before 2,30pm we will ship to you the same day.

Click here to view our catalogue that shows the complete range of sizes available

If you cannot see what you are looking for in the catalogue please feel free to email or call us to discuss your requirements.

Tel: 01424 447726 Email: [email protected]