Greer Company
Greer Company
Greer Company
Greer Company
Crane Systems
1918 EAST GLENWOOD PLACE, SANTA ANA, CA 92705
Tel: (714) 259 9702 Fax: (714) 259 7626
MicroGuard
424 Operation/Troubleshooting Manual Horizontal Display Hydraulic Cranes
33 of 52
W424103 REV A 02/13/01
ACCESSING MAIN COMPUTER BOARD
ACCESSING MAIN COMPUTER BOARD
ACCESSING MAIN COMPUTER BOARD
ACCESSING MAIN COMPUTER BOARD
AND TERMINATION BOARD
AND TERMINATION BOARD
AND TERMINATION BOARD
AND TERMINATION BOARD
1. Remove the four screws (1) securing the computer
lid to the computer box. This lid is NOT hinged. Take
care
not
to allow the lid to fall from the box. Set the
lid aside.
2. Under the lid you will see the Main Computer Board.
This board contains the microprocessor and its
related components. This unit is held in place by two
screws (2) located at the left and right of the Main
Computer Board backing plate and is connected to
the Terminal Connection Board via 2 ribbon cables.
These cables carry the signals to and from the
Termination Board. These will be to the top of the
Main Computer Board.
3. If you are going to check voltages on the Termination
Board, remove the two screws located at the left and
right of the Main Computer Backing Plate and swing
the assembly up. Take care not to damage the
ribbon cables. These ribbon cables must remain
connected to the Main Computer Board for voltage
checks.
CHECKING ANALOG DRIVE VOLTAGE
CHECKING ANALOG DRIVE VOLTAGE
CHECKING ANALOG DRIVE VOLTAGE
CHECKING ANALOG DRIVE VOLTAGE
To check the Analog Sensor Drive Voltage, use the
following procedure:
1. Access the Termination Board.
2. With the system power on and a digital volt meter set
to read DC voltage, place the negative lead on any -
DR (- Drive) terminal (1) of the Analog Input Group.
3. Place the positive lead of the meter on any +DR
(+ Drive) terminal (2).
4. The voltage should be 5.25+/-0.1volts.
5. If the Analog Drive Voltage is not within this range,
disconnect all of the external sensor cables,
including pressure transducers, cables 1 through 5.
6. Recheck the Analog Drive Voltage. If the voltage is
still out of range, the Computer Board will need to be
replaced. If the voltage is within range, reconnect
each cable, one at a time, checking the Analog Drive
Voltage after each cable is connected.
7. If after reconnecting any one of the sensors the
Analog Drive Voltage goes out of range, it is
probable that the wiring to the sensor is grounded or
the sensor itself is faulty.
Check all wires and the sensor itself and repair or
replace as required
.
+ D R
0V
-D R
+ D R
0V
+ D R
-D R
-D R
0V
A IN 0
0V
0V
A IN 2
A IN 1
-D R
A IN 5
A IN 6
A IN 3
0V
0V
+ V P
+ V P
+ V P
+ V P
0V
+ D R
+ D R
0V
TX 0-
TX 0+ A IN 4
TX 1+
TX 1-
-D R
D RIV E
V O LTA G E
5.25 + /- 0.1
The analog drive voltage can be
m easured betw een any D R+ term inal
and any D R- term inal. It is 5.25volts
D C + /- 0.1 volts.