Fuse blows at top temp
Posted: Mon Nov 28, 2016 5:42 am
I'm hoping someone can help me with this issue.
My kiln is self built, it has been running for a few months now in the basement. Two days ago, for the first time, blew the fuse when it was at the top temperature (740 C/1360 F) for its firing. I replaced the fuse (an old screw type fuse), thinking it was just at the end of its life. Yesterday the fuse blew again on a similar firing. The kiln has gone up all the way to 960 C (1760 F) before without any problems. The fuse is rated for 20 amps and the kiln should only be drawing 14 amps. The elements are cycled on/off in 10 second windows, so its either drawing full capacity or nothing at all. The fuse was blown while on a holding phase, the elements are on for a shorter amount of time than while ramping up, so I think it couldn't be a continuous load problem.
Does anyone have a suggestion for what could be the problem here? I am stumped.
My kiln is self built, it has been running for a few months now in the basement. Two days ago, for the first time, blew the fuse when it was at the top temperature (740 C/1360 F) for its firing. I replaced the fuse (an old screw type fuse), thinking it was just at the end of its life. Yesterday the fuse blew again on a similar firing. The kiln has gone up all the way to 960 C (1760 F) before without any problems. The fuse is rated for 20 amps and the kiln should only be drawing 14 amps. The elements are cycled on/off in 10 second windows, so its either drawing full capacity or nothing at all. The fuse was blown while on a holding phase, the elements are on for a shorter amount of time than while ramping up, so I think it couldn't be a continuous load problem.
Does anyone have a suggestion for what could be the problem here? I am stumped.