Bending OT

ERROR: Bending OT Item 294

The bending magnets are cooled by water. When the water flow is obstructed the coil temperature rises. The temperature is monitored by a number of so-called "Clixons", small temperature sensitive bi- metal based switches. If the temperature rises above about 50 degrees C the contact opens and the screen shows the ERROR Bending O/T item 294. And the power automatically will be shut downed!

It is beneficial to monitor the Bending voltage Item 584 at regular intervals. As the resistance of the bending coils is proportional with temperature, an increase of the bending voltage indicates reduced cooling. So you are moving into the danger zone!

(This is best observed with high bending currents: high current means high voltage, hence high power, hence high temperature! Don't over do it!). The obstruction of the water flow can be located in the hoses, in the manifolds, or in the coils themselves. Carefully inspect these items and once found the culprit, try to eliminate the problem. Use wire, pressurised air or whatever comes in your mind. Be careful with air: don't apply it in the same direction as the water normally flows! The obstruction must be REMOVED! Not pressed in further....

A simple way to determain which magnet is causing the trouble is to lift the head plus primary diaphragm and feel which coil is the warmest

BTW. After changing the type of hoses (connected to the manifolds), a couple of years ago the frequency of this problem was reduced to a minimum.

When reconnecting coils to the manifolds, prevent mechanical stress. Otherwise you end up with nasty water leaks.