Richard Aiken wrote:

    Maybe (a la Star Trek) make it give a warning tone, as overload approaches?
    Plus a "safety" feature that focuses the blast (once this is unavoidable) into a rough cone . . .
    Which would - of course - mean that enterprising PCs would rig them as one-shot blasters . . .
    Which is okay. I've got no objection to PCs [literally] blowing credits on expensive disposable weapons.

All excellent suggestions. Thanks!