R&M Materials Handling WIRE ROPE HOISTS Service - Manual (Page 103)

R&M Materials Handling, Inc.
4501 Gateway Boulevard
Springfield, Ohio 45502
P.: (937) 328-5100
FAX: (937) 325-5319
103/130
R&M Materials Handling, Inc. reserves the right to alter or amend the above information without notice.
5.33 Load signal amplifier
The load signal amplifier amplifies the signal coming from the load sensor. The amplified signal is fed into
the condition-monitoring unit. The LED’s indicate the load, in percentage of the rated load of the hoist.
0% LED lights up when the lifted load is equal or less then 0% (indicating slack rope) whereas the 100%
LED lights up when the load is equal or bigger then 100% (indicating overload).
ZERO
GAIN
0 V SIGN 10 V -IN +IN
1 2 3 4 5 6 7 8 9 10
0 %
100 %
c_esd142a
5.33.1 Adjustment
Adjustment with no load:
• Check that there is no load on hook.
• Adjust the trimmer "ZERO" to counterclockwise until the light "0 %" goes on.
• Adjust the trimmer "ZERO" back to clockwise until the light "0 %" goes off. Now the output signal
should be about 4 VDC. Voltage can be measured between the terminals 1 and 3.
Adjustment with nominal load:
#
You may have to bypass overload protection on condition monitoring unit when lifting a test load.
Adjustment with 100% load:
• Lift up the rated load of the hoist.
• Adjust the trimmer "GAIN" clockwise until the light "100 %" goes on.
• Adjust the trimmer "GAIN" counterclockwise until the light "100 %" goes off. Now the output signal
should be about 6 VDC. Voltage can be measured between the terminals 1 and 3.
If a 100% test-load is not available, adjustment can be done with any known load in between 50…110%
of the rated load. In that case, the output voltage with the respective test load has to be calculated as
follows:
4 2 +






× =
r
t
out
L
L
U
U
out
= Output voltage
L
t
= Test load
L
r
= Rated load
Adjustment with 50…110% load:
• Lift up the known test-load.
• Connect a Voltmeter between terminals 1 and 3.
• Adjust the trimmer "GAIN" clockwise until the voltmeter shows the correct respective voltage.