Installation manual
4
IMPORTANT SAFETY INSTRUCTIONS
Secondary Means of Protection Against
Entrapment
As specified by Underwriters Laboratories Inc. UL 325 (30A.1.1), automatic gate openers shall have provisions for, or be
supplied with, at least one independent primary and one independent secondary means to protect against entrapment. The
Mighty Mule Gate Opener
®
utilizes Type A, an inherent (i.e., built-in) entrapment sensing system, as the primary type of
entrapment protection. Also, the Mighty Mule Gate Opener
®
has provisions for the connection of Type B1 or B2 protection
to be used as the secondary type of entrapment protection, if desired.
1. For gate operators utilizing a non-contact sensor (e.g., photoelectric sensor– Type B1) in accordance with
UL 325 (51.8.4 [h]):
A. Refer to the sensor manufacturer's instructions on the placement of non-contact sensors for each type of application.
B. Care shall be exercised to reduce the risk of nuisance tripping, such as when a vehicle trips the sensor while the gate
is still moving.
C. One or more non-contact sensors shall be located where the risk of entrapment or obstruction exists, such as the
perimeter reachable by a moving gate or barrier.
2. For gate operators utilizing a contact sensor (e.g., safety edge sensor– Type B2) in accordance with UL 325 (51.8.4 [i]):
A. One or more contact sensors shall be located at the leading edge, bottom edge, and post mounted both inside and
outside of a vehicular swing gate system.
B. A hard wired contact sensor shall be located and its wiring arranged so that the communication between the
sensor and the gate opener is not subjected to mechanical damage.
C. A wireless contact sensor such as one that transmits radio frequency (RF) signals to the gate opener for
entrapment protection functions shall be located where the transmission of the signals are not obstructed or
impeded by building structures, natural landscaping or similar obstruction. A wireless contact sensor shall
function under the intended end-use conditions.
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PWR. SW.
Entrapment Alarm
(bottom right of control box)
ENTRAPMENT ALARM (UL 325; 30A.1.1A)
The Mighty Mule Gate Opener
®
is designed to stop and reverse approximately 2 seconds when the gate comes in
contact with an obstruction or when an object activates the non-contact sensors. Additionally, these openers are
equipped with an audio entrapment alarm which will activate if the unit obstructs twice while opening or closing.
This alarm will sound for a period of 5 minutes, or until the opener receives an intended signal (e.g., from a
transmitter) and the gate returns to a fully open or fully closed position.