Our quick start guide offers useful tips to help you install Comet Vacuum Capacitors

December 19, 2023

Learn how to mount Vacuum Capacitors in 3 simple steps.

1. Positioning

Convection and forced air cooled capacitors can be mounted in any position:

horizontal

vertical

2. Mounting

As a good engineering practice, we strongly suggest mounting only one side on a rigid platform, with the opposite side connected to a non-rigid plane (or strap). This prevents excessive thermo-mechanical and/or external forces from damaging the capacitor.

3. Installing

Most Comet Vacuum Capacitors are equipped with copper mounting flanges at both ends, as shown on the individual product data sheets. These rings have threaded holes aligned to within 2º. We suggest using these mounting flanges for all mechanical and electrical connections.  

Where space permits, Comet provides two sets of holes per ring containing both metric threads and American Standard threads (UNC). Many standard solid flanges contain 6 metric thread holes alternating with 6 inch-sized thread holes.

In some cases, the mounting provision is provided only on one side, with the other side requiring a special flange. Wherever possible, Comet will furnish an integral flange on both sides on request.

Maximum admissible tightening torque [Nm]

  

M4

M5

M6

M12x0.75

  Basic-Con

1

     

  Uni-Con

1

2

2

 

  Tetra-Con

2

     

  Hexa-Con

2

 

2

 

  Mini-Cap

2

   

 

  Trimmer-Cap

     

2

For the admissible tightening torque of other Comet Vacuum Capacitor series, refer to our Service-Bulletin 27.

 Handle with care

Modern ceramic Vacuum Capacitors appear very rugged. But due to the brazing process used to join ceramic and copper, the copper in a soft, annealed condition and highly susceptible to mechanical deformation. For this reason, avoid any rough handling, such as machining of the flanges. Use existing holes and threads for installation and consider the torque limits in the table above.

Mark Mildner
R&D Director
Comet Plasma Control Technologies Switzerland

"Installing Vacuum Capacitors requires extreme care. Handle delicately to avoid damaging the body of the capacitor, which can easily displace the electrodes." 

Special note:

Water Cooled
Vacuum Capcitors

Water cooled capacitors call for additional precautions during mounting. Water pressure should not exceed the type specific pressure at inlet any time but sufficient flow has to be provided. The required water flow is indicated on the individual data sheet on the current curves.

Additionally, the maximum outlet temperature should not exceed 80°C, or less if specified on the individual data sheet.

For required water quality, see Service Bulletin SB-26 "Liquid Cooling System and Water Purity Requirements."

We offer full technical and engineering services. If you require help with mounting your Comet Vacuum Capacitors, please contact our technical department for assistance.

Further

readings

SB-27

Refer to our Service-Bulletin SB-27 for more background about installing Vacuum Capacitors.

More

Vacuum Capacitors
product range

Technical
data sheets

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