PAG OERLIKON AG
SERIES-300 S / SCS
ELEMENTARY DIAGRAM / PRINZIPSCHALTBILD
FUNCTIONAL DESCRIPTIOIN
Weighing System Description
Mechanics
The force caused by any weight which is placed on the weighing pan [1] reaches the support [2] directly. The
support [2] is sustained in a parallel configuration by the top [3] and bottom [4] flexure arms. The support [2]
leads the force through the flexure strap [5] to the balance arm [6] . The arm [6] is connected to the flexures
[15] on the chassis [14] . The balance arm [6] leads the force with a certain reduction ratio to the compensa-
tion coil [13] which is located in the center of the magnetic-system.
Magnetic-System
The magnetic system consists of a permanent magnet [9] and the pole piece [10] . They lead the magnetic
field to the compensation coil [13] . The magnetic system, is covered by a screen [12] , to inhibit the break-out
of the stray-field.
Balance arm location
The position of the balance arm [6] is set by the light detector [8] which gets the light through the vane [7].
Measure principle and regulation
Any weight placed on the weighing pan [1] moves the balance arm [6] from its zero-position. The light
detector [8] gives the deviation from the zero-position as an electric signal to the input amplifier [16] and to
the PID-Regulator [17] . The PID-ReguIator [17] changes its output voltage, which goes via the power
amplifier [18] to the compensation coil [13] , till the force change on the coil [13] is sufficient to put the
balance arm [6] back to its initial zero-position. The position of the balance arm [6] , is in the steady-state
now, and the current through the coil [13] is proportional to the weight placed on the weighing pan [1] .
Electronical Evaluation of the Measure Current
The coils’ current is converted to a measure voltage by the measure resistor [19] . This measure voltage
goes on the one side via the buffer-amplifier [22] , to the analogue display [25] , and the analogue output [38]
; on the other side it feeds the analogue to digital converter [20] (AD-Converter) . The AD-Converter [20]
compares the signal with the reference voltage source [23] . The AD-Converter [20] works in the “Dual-Slope-
Method” and is controlled by the microprocessor [27] by means of the AD-Logic [21] . The digital output signal
reaches the microprocessor [27] through the counter [24]. The Reset-Logic [35] supervises the power supply
[36] and enables the microprocessor [27] to run, if there is sufficient supply voltage. The microprocessor [27]
sends the display-data to the display-controller [31] , where the data is latched and displayed by the dispIay
[32] .
The keys “ON/OFF”, "MODE" and “T” [34] give information through the driver [33] to the microprocessor . If
the balance is switched off by the “ON/OFF”-key, it remains in the “standby” mode, that means the balance is
ready to work with no warm-up time after switching on again.
A 01.03
Summary of Contents for 300 SCS series
Page 1: ...PAG OERLIKON AG The Balance of Quality SERVICE MANUAL SERIES 300 S 300 SCS 300 SIP...
Page 135: ...PAG OERLIKON AG SERIES 300 S SCS SIP MAIN BOARD 300 7218 010 HAUPTPRINT 300 7218 010 C 01 03...
Page 150: ...PAG OERLIKON AG SERIES 300 S SCS SIP MAIN BOARD 300 7235 010 HAUPTPRINT 300 7235 010 C 02 06...
Page 159: ...PAG OERLIKON AG SERIES 300 S SIP ANALOGUE BOARD 300 7219 010 ANALOGPRINT 300 7219 010 C 03 01...
Page 162: ...PAG OERLIKON AG SERIES 300 SCS ANALOGUE BOARD 300 7238 010 ANALOGPRINT 300 7238 010 C 04 01...
Page 194: ...SERIES 300 S SCS SIP PAG OERLIKON AG CALIBRATION INSTRUCTIONS D 04 11 Final control...
