MAGNET POWER SUPPLY SYSTEM 7000
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DANFYSIK A/S - DK 4040 JYLLINGE - DENMARK.
4.3.3
Interlock and ON/OFF/STANDBY status
This block processes the interlock and ON/OFF/STANDBY status signals.
Internal and external interlock and status signals are connected directly without galvanic
isolation.
The latched interlock information can be seen from the LED’s, on the local control panel and
from the remote serial line (Digital interface plug).
Each interlock is individually connected to a SR latch. Every time an edge transition is detected
it will be latched in a SR latch. The first one though will be latched on arrival of the delayed
sum interlock.
This circuit consists of the integrated circuits U701, U705, U707 and U712.
4.3.4
Over Current Interlock
The task of the overload protection is to turn the power supply OFF if the output current rises
above adjusted level that is adjustable by means of P807.
This circuit is build upon U807.
When the power supply delivers 100% output current, the DCCT delivers exact 0,1A. This
0,1A current is fed through a 10
S
resistor in the Regulation Circuit, sheet 2, and giving 1V and
then amplified by 10 gives10V. If this rises above adjusted threshold at the comparator U807,
transistor Q804 will open and an overload interlock is activated.
4.3.5
Out of Regulation Status
The output voltage from the "ERROR" amplifier located in the compensation loop circuit is
proportional to the accuracy of the output current. Since the gain in the ERROR amplifier is
known, the window discriminator U802 is able to test, if the output current lies within the
desired level. The window span (R807, R814, R822 and R824) is calculated to 2.5%.
4.3.6
Power Output Over Voltage Interlock
If the output voltage of the Power Amplifier exceeds the adjusted threshold level, interlock is
activated.
Threshold level is adjusted at P802.
