Dillon DynaSwitch - Manual (Page 19)

19
6-3
Cranegard Field
Installation Procedures A. The Cranegard is designed to be mounted on a slack line. If line is not
slack, methods should be employed to shunt load in the cable area
where Cranegard will be installed. Often wire grips and portable
winches are used to accomplish this.
B. Position the Cranegard at the desired location on wire and loosely attch
the clamp wit the included screws. Tighten the screws so that the
cable is loosely gripped between the top and the bottom of the clamp.
Insure the same gap exists between the upper and lower clamps on
both sides.
C. Check switch operation using a voltmeter or other method for monitor-
ing open/closing of switch contacts. If specific loads were indicated at
the time of order, Dillon will calibrate to these values at the factory
prior to shipment. Once installed, there may be diffrences between
calibration and actual trigger values. Differences in rope type &
diameter, temperature, and external mechanisms (such as sheaves)
can affect the switch activation points. If more precise calibration is
required, it should be calibrated under the conditions used.
D. If field calibration is required, follow the additional instructions below.
E. Remove the protective cover to expose adjustment screws.
F. Refer to Paragraph 2-6, Notes 1 and 2, for information on construction
of a test assembly for switch adjustment.
G. Figure the desired set point for each microswitch. In setting two, three
or four switches, set the highest set point first, then work down accord-
ing to weight. Any other sequence will cause a shutdown during the
adjusting process.
H Turn the adjustment screw(s) counterclockwise, away from the
microswitch plunger(s) as far as possible.
I. Apply the trigger load, insuring that the cutoff load is approached from
the desired direction. For increasing loads, such as overload detection,
gradually apply the load. For decreasing loads, such as slack-line
detection, apply at least 5% more load (of Cranegard capacity) than is
desired for switch trigger, then gradually reduce the load until trigger
load is reached.
J. Slowly turn the adjustment screw until it contacts the microswitch
plunger and the switch actuates. Then tighten the jam nut to hold the
adjustment.
K. Remove, then reapply the load to check the set point. It is properly set
if the machinery (or the test assembly) functions as planned within
desired tolerances.
L. Repeat steps G through K as many times as required to obtain correct
settings.
Figure 6-B