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
37 of 52
W424103 REV A 02/13/01
BOOM EXTENSION SENSOR AIN2
BOOM EXTENSION SENSOR AIN2
BOOM EXTENSION SENSOR AIN2
BOOM EXTENSION SENSOR AIN2
Use the following procedure to check the Boom
Extension Sensor Voltage.
1. Fully retract the boom.
2. Access the Relay and Termination Board.
Measure the analog sensor drive voltage (refer to
page 36
of this manual).
3. With a digital voltmeter set to read DC voltage place
the negative lead on any 0 Volt terminal of the
Analog Input Group.
4. Place the positive lead of the meter on the AIN2 2
terminal of the Analog Input Group. The voltage
should be 0.25 volts
±
0.1volt.
5. Extend the boom as far as safe to do.
The boom
need not be horizontal for this test.
6. The voltage should be less than 5 volts. (Usually
around 2.5 volts depending on the boom length).
7. During extension the voltage should increase linearly
and during retraction the voltage should decrease
linearly.
8. If the voltage is out of the range listed above, remove
the four screws securing the cover on the extension
reel located on the left side of the main boom section
and remove the cover.
9. Under the cover on the right side of the extension
reel you will see a terminal strip. This terminal strip
has six wires connected to the bottom screws.
10. With a digital voltmeter set to read DC Voltage, place
the negative lead on the terminal with the blue wire
attached to it (- Drive) and the positive lead on the
terminal with the red wire attached to it (+Drive).
11. The voltage should be 5.25
±
0.1 volts. If this voltage
is out of range and the Analog Drive Voltage
measured in the computer was OK then it is possible
that the cable is open or grounded between the
Computer and the Extension Reel. Check all
connections and plugs that may be between these
two components. Repair or replace as required.
Refer to the MicroGuard 414 wiring details in the
Installation Manual for the model of crane under test.
12. With the negative lead of the voltmeter connected to
blue, drive negative and the positive lead of the
voltmeter connected to white, extension signal, the
voltage should be the same as the voltage measured
at AIN2 of the analog input group in the computer. If
this voltage is not the same, it is possible that the
cable between the reel and the computer is faulty.
+ 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
A IN 2, V O LTA G E
V A RIES W ITH
BO O M EX TEN SIO N
RED
D R +
W H ITE
D R-
BLU E, SIG N A L TO
A IN 2