28 The GS550 System
2.6 Radius
2.6.1 Radius Verification and Adjustment
1. Verify the boom and luffing jib
*
angles, and the boom length
†
, are indicated correctly.
2. Verify the correct rated capacity chart is selected
‡
.
3. Test № 1: measure the actual radius and compare to the radius indicated. Repeat with the
boom at minimum angle, at 45 degrees, and at maximum angle; repeat at minimum and maxi-
mum boom length
†
. If radius indication is not accurate then go to step 4.
4. Measure the basic radius parameters on the crane (see pages 31 and 32).
5. Program the basic radius parameters in the radius settings menu (see page 29).
6. Test № 2: measure the actual radius and compare to the radius indicated. Repeat with the
boom at minimum angle, at 45 degrees, and at maximum boom angle; repeat at minimum and
maximum boom length
†
. If radius indication is not accurate then go to the next step.
Tip
If the difference between the displayed radius and actual radius remains constant at all
boom lengths and angles, then correct by adjusting the slew offset. For example: if the
radius displayed is always 2.3 feet longer than the actual radius, then subtract 2.3 from the
slew offset.
7. If the crane is rigged with the main boom only, then go directly to step 11.
8. If the crane is rigged with a rooster, jib, or other extension then the advanced radius parame-
ters must be measured on the crane (see page 33), and then programmed in the radius set-
tings menu of the display (see page 29).
9. Test № 3: measure the actual radius and compare to the radius indicated. Repeat with the
boom at minimum angle, at 45 degrees, and at maximum boom angle; repeat at minimum and
maximum boom length
†
. If radius indication is not accurate then go to the next step.
10. Test for boom deflection: is the radius indicated equal to the actual radius with the boom at 0
degrees and at 90 degrees but greater than the actual radius with the boom at 45 degrees? If
yes then adjust the boom deflection value to compensate:
a. Raise the boom to 45 degrees with a known load.
b. Compare the indicated radius with the actual radius. Change the boom deflection value
and again compare the radius displayed with the actual radius. Repeat until the radius
displayed equals the actual radius.
*
When the hoist is rigged off a luffing jib only
†
Telescopic boom cranes only
‡
Systems with rated capacity charts programmed in the GS550 only