© Ernst Nagel GmbH 2S Trimmer Service Manual en.doc Rev.1.0. 20.07.2011
124
Contents
7. PCB’S
(continued)
7.2 LED’S & TEST POINTS
(continued)
7.2.2 CPU PCB6 & PCB7
Attention!!!
Only for Standalone make sure the Mode Selection plug [
6P13
] (See Chap.
2.2.4
) is
present. Otherwise communication problems can arise.
This board controls the machine on a higher level then the
motor control boards.
It also measure 36V Unreg and 24V Regulates power on the
Interlock
Board.
D5: Yellow LED flashes when power is on. The flashing
indicates that a program is present and functioning.
Should a download fail or the 5V is missing, Yellow LED
would be OFF.
Fig. 7.8
VCC
:
Stabilized and rectified 5V made from incoming 10V AC from transformer.
Measure between Test Point VCC and Test Point GND/PGND using a voltmeter. The voltage will
be shown on the voltmeter. Range 4.9-5.1V.
GND
:
Ground is the minus when measuring 5V (VCC).
R41
:
Trim Potentiometer for Contrast setting of the LCD.
7.2.3 Softstart PCB4
This board controls the power on the machine. When the power is turned on there will
be a very high current peak for a short while. To limit this current peak the Softstart
PCB is used. The current peak will flow through a resistor (PTC, cold resistance 18R)
and the start current is limited to 12,7A (230VAC/18R=12,7A).
After about 20ms the relay will short circuit the resistor and the machine is ready to use.
D5
VCC
GND
R41