SPECS EBE-1, Руководство пользователя

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Operation with the Flux Controller
To set “Manual control”, PID access must be set to FULL. The “Page” button is the left-
most button on the PID controller. The “Scroll” button is the next button from the left.
Then follow the up and down arrow buttons.
Press the “Page” button 8 times until “ACCS List” is displayed. Press the “Scroll” button
once until “Code 0” is displayed. Use the up arrow button until “1” is selected. After a
brief pause the display will show “PASS”. Press “Scroll” once. “Goto Oper” will be
shown. Press up arrow once and “ACCS FULL” will be displayed. Press “Page” twice to
get the two rows of digits displayed. The upper digit is the measured value of flux cur-
rent and the lower value is the PID output (in Man mode) or the Set Point in Auto
Mode.
Now with FULL ACCESS set it is possible to select manual mode. Press “Scroll” twice and
“m-A” will be displayed on the upper line and “mAn” or “AUTO” on the lower line.
Use the arrow keys to select “mAn”. The controller is now in “MANUAL” mode and the
green light should be on. Press “Scroll” three times to get back to the display with the
measured value. The arrow keys can now be used to directly control the PID controller
output.
Set the Man/Auto switch to Auto.
4.4.2 Setting the Maximum and Minimum Output
Set the Set point on the PID controller to some value which is considerably greater than
the measured current value, this will ensure that the controller tries to provide maxim-
um output. Now set the maximum output of the controller to 30 %. Set the Man/Auto
switch to Auto. The power supply is now under the control of the PID controller which
will be trying to give full output in order to bring the flux current up to the required
level. But it will be prevented from doing so by the fact that the maximum output drive
is limited to 30 %.
Increase the Maximum Output setting of the PID controller in 5 % steps (smaller as the
required value is reached) until the filament current (and therefore the emission cur-
rent) is slightly higher than the value recorded during manual evaporation. Note if the
allowed filament current is too much higher than that required, the possible emission
current could be too high for the material being evaporated, causing rods to melt or
the crucible contents to boil. Be sure to check that the emission current at no time ex-
ceeds allowed limits for the material being evaporated.
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