Autoquip FREIGHTLIFT FL4M - Manual (Page 68)

68
L. INSTALLING SLACK CHAIN SENSING SWITCHES (Reference Figures 38a&b)
Items needed:
Qty
Description
4 Slack Chain Sensing Switch Kit – Lifting Chains
Kits have been shipped loose to be field mounted, wired, and adjusted per the
procedure below for the lifting chains. Sensing switches have been pre-mounted (but
not been adjusted) onto the drive base for the drive chains. All these switches are
intended to turn off the motor and arrest movement of the carriage whenever a
slack/broken chain status is sensed.
DANGER !
To avoid personal injury or death, the procedures described in this section
should only be performed by qualified service personnel.
LIFTING CHAINS (Figures 38a & 38b)
1. To install these slack chain sensing switches, first gain a safe access to the drive
base at the top of the masts. There is a slack chain sensing switch kit provided for
each lifting chain, (4) total.
2. With the carriage hanging from the chains, each tensioner bar will be pushed
towards the sensing limit switch rotating arm. Each switch is to be wired normally
open – held closed.
a. Mount the sensing switch to the mounting plate using the 10-24 x 1-1/4” lg
hardware provided as shown (Fig 38a)
b. Locate the ship-loose switch arm assembly, keep it close by – you’ll need
it in step e.
c. With one hand, use a pair of needle-nosed pliers to grip the sensing
switch actuator near the base of the actuator and then rotate the actuator
away from the tensioner bar until the switch “trips” and the contacts close
(listen for the “click”).
i. Clockwise for the Left side beams
ii. Counter-clockwise for Right side beams
d. Once you hear the “click”, turn the actuator an additional 1/8
th
of a turn
and hold in place
e. Now, with your free hand, pick up the switch arm assembly that you have
close by and push it onto the end of the sensing switch actuator until the
end of the actuator is flush with the top of the switch arm – making sure
that the roller on the end of the arm is making contact with the tensioner
bar as shown. (Fig. 38b)
INSTALLATION INSTRUCTIONS