Switching Spark Gap

Power Circuit Protection
,
1

I’m looking for a replacement for the 1kV switching spark gap.
Bourns, Okaya and EPCOS have also discontinued production and have not been able to find another manufacturer producing switching spark gaps.
①Is it possible to replace with a gas arrester?
②Is it possible to replace 3pcs 350V switching spark gaps with a series connection?

2

Tetsu

Here is a couple answers from the engineers we have .

Not sure I understand what specific device/parameter the customer is looking for. It looks like we have several 1000V devices available https://www.digikey.com/short/fc7vbv0r .

These products would be classified as Gas Discharge Tubes

  1. I would expect the voltage ratings of multiple GDTs in series to be additive to a first estimate, though the detailed electrical characteristics might change a bit. The voltage appearing across each device may be slightly different, due to variations in device capacitance. This difference could be equalized when the tube enters a “glow” state prior to a full arc developing, but I’m not sure how this would affect how a series array would respond to fast events, compared to a single device.
  2. I’m not sure what kind of precautions you’re thinking of. Could you please describe further?
  3. GDTs for surge arrest applications are not expected to operate frequently (maybe 10’s of times) and may include mechanisms to cause the device to enter a permanent short-circuit condition when overloaded. They are also characterized in terms of their behavior under standard circuit protection conditions, using 8/20 or 10/1000 waveforms. In contrast, switching GDTs are designed for regular, frequent operation and may last into the millions of operations, rarely have fail-safe provisions, and are not characterized using the methods common for circuit protection applications. It is likely that using a GDT designed for circuit protection will not last very long in a switching application.
  4. Does the customer have a datasheet or part number for the product they are trying to replace? What is the application? The switching GDTs in the linked document from TDK appear to be obsolete, and I’m not seeing devices of a similar kind described by any of the other major manufacturers that we have listed. I suspect that it is a technology that, for switching applications at least, is falling out of favor.

These questions are spoken to in the response above. In summary:

  1. Maybe, but it’s not likely to be a durable solution
  2. Maybe, but the behavior isn’t likely to be quite the same
3

Thank you for reply.

I am looking for a replacement product for the discontinued FS1X-1G (manufactured by EPCOS).
PCB mountable axial component with 1kV switching spark gap.
The application is an ignition for lighting discharge lamps.

As you pointed out, I’m worried about repeated use of GDT, so I’m looking for a switching spark gap. What about other high voltage ignition circuits?