9 conducting a grinding operation, 1 overload, 2 interrupt a grinding process – FRITSCH PULVERISETTE 4 classic line User Manual

Page 37: Using the device

6.9 Conducting a grinding operation

Press the START button on the control panel.

The hood is locked and the mill starts up.

The mill turns at the set speed (nominal speed). If the load is too

great, for example due to heavy grinding bowls, the speed is reduced

(actual speed) so that the machine is not overloaded.
® If the mill does not start, see Ä Chapter 10 ‘Repairs’ on page 47

While in operation, the hood remains locked, even during

pause times, and the fan cools the interior.

6.9.1 Overload

If the mill is overloaded, the rotational speed is reduced.
The mill switches off if the overload continues for too long; see

6.9.2 Interrupt a grinding process

After selecting the program and pressing the START key on the mill,

an internal timer begins to run. It is possible in this way to check the

milling progress by pressing the STOP key on the machine, checking

the grinding state and then pressing the START key again on the

machine to continue the grinding with no loss of time. Also if the mill

is stopped during the pause time, the milling will be continued after

pressing the START key.

If the START button is pressed in the PC program, all total times will

be transferred, whereby no residual running times or pause times

will be taken into account. The grinding starts again from the begin-

ning.

The residual times are saved after every hour as a precaution. If

milling is performed over a longer time period and the electrical

power is cut off, the residual time can be re-run (maximum ina-

curacy is < 1 hour). Functional principle: When the mill is recon-

nected to electrical power, the software recognises the residual time

stored and indicates this through a 0 in the display. If the START key

on the machine is now pressed, the grinding is continued.
The residual time can be read off in the program.

Using the device

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