electric elements.?

Now that you have heard the crap answers, you have a shorted element. The actual heating element is inside a steel tube insulated with a high temp ceramic material. Sometimes that material breaks down and allows the element come in contact with the metal tube grounding it out.

If you check from terminal to terminal you will have continuity of the element. If you take one lead of your meter to a terminal and one to the metal case you should see the continuity of you short. Be very carful when you are checking this under power so you don't get electrocuted.

I gave my answer in the comment area. You have a defective (shorted) heating element. Locate which one it is and replace it.

The same can happen to an electric water heater element.

I have been trying to isolate a problem on an oven which sets off the tripper. The oven has a double grill at the top consisting of two elements. I disconnected the oven from the mains. I checked the elements for continuity using a multi-meter and found no problem, I wired the elements up individually and they glowed red hot. The problem I found was that the oven itself became live. In supplying energy to the elements I used no earth, but surely as the elements are insulated they should not leak current?

electron, hole conducts electricity

There are no electric elements. There are electronically charge particles that make up an element. The primary ones are electrons and protons.