Every installation is unique, therefore there are only a very few hard
and fast rules to follow. First of all, observe all safety
requirements, procedures, and local codes. Secondly, the cable switch
must be mounted on a flat surface. Bolting the switch to an irregular
surface can cause the housing to be twisted and alter the function of
the switch. The first cable support must be located 6 to 12 inches from
the switch and in line with the switch shaft within 5 degrees. It is
recommended that the balance of the cable supports be spaced at
intervals not exceeding 10 feet. Long unsupported spans of cable will
sag causing the operator at a different location to "pull up" that slack
before actuating the switch. Unmanned sections of the cable can be run
through open ended conduit affording maximum support and protection.
This is also a very good way to route the cable around a corner if
necessary. A larger radius curve can be bent into a short piece of
conduit than can be obtained with a pulley. The operating force of a
cable switch is dependent upon the distance between the cable supports
and the total distance the cable has to be pulled to actuate the switch.
Our switch "Instruction Sheets" chart these forces and can be used as a
guide for the desired installation. It is recommended that the cable
length does not exceed 200 feet and be in as straight a line as
possible. This recommendation, as with the others given can be
circumvented by the experience, knowledge, and good sense of the
installation supervisor. Cable weight is another factor to consider,
as too heavy cable may impair the system function by placing too great
a preload on the switch. The use of a turnbuckle and/or an anchor
spring in line with the cable will facilitate the installation and
adjustment of the cable system. All cable materials will stretch with
use and when subjected to varying temperature swings. This is more of
a problem on longer runs than on shorter ones, so the cable must be
regularly checked and readjusted to maintain the desired cable tension.
These switches, as all mechanical devices, will wear out and
eventually need to be replaced. The estimated minimum mechanical
life is 150,000 operations. Regularly scheduled preventive
maintenance inspections are strongly recommended for these switches.
Some items to watch for are: Physical damage to the
switch
Damage to
the cable, particularly at the points that it passes through its
supports
Loose connections or components
The cable out of
adjustment!
If other assistance is desired, please contact the factory.
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