gb wrote:
I had always seen ceramic -- instead of glass (fuses) -- in this
applicaiton

A lot of HV fuses are filled with a ceramic powder or with boric acid to
quench the arc faster when they break. If you do that, there's no reason
to use a glass tube since there's nothing to see inside anyway.

The ceramic cases are also less apt to explode when the fuse blows.
--scott

--
"C'est un Nagra. C'est suisse, et tres, tres precis."