The sensor must meet a minimum environmental rating of IP54. When the sensor is specified for immersion in water, the
sensor’s minimum environmental rating must be IP67. Special attention may be required to the interconnect cabling;
wicking action may result in the ingress of liquid into the mat, possibly causing loss of sensor sensitivity. The termination
of the interconnect cabling may need to be located in an enclosure that has an appropriate environmental rating.
The sensor must not be adversely affected by the environmental conditions for which the system is intended. The effects
on the sensor of liquids and other substances which can be expected must be taken into account. For example, long-term
exposure to some liquids can cause degradation or swelling of the sensor’s housing material, resulting in an unsafe
condition.
The sensor’s top surface should be a lifetime non-slip design, or otherwise minimize the possibility of slipping, under the
expected operating conditions.
The four-wire connection between the Module interconnect cables and the sensor must withstand dragging or carrying the
sensor by its cable without failing in an unsafe manner (for example, broken connections due to sharp pulls, steady pulls,
or continuous flexing). If not, an alternate means must be employed to avoid such a failure, for example, a cable which
disconnects without damage and results in a safe situation.
Installation
The mounting surface quality and preparation for the sensor must meet the requirements stated by the sensor’s
manufacturer. Irregularities in the floor (or other mounting surfaces) may impair the function of the sensor and therefore
should be reduced to an acceptable minimum.
The mounting surface should be level and clean. Avoid the collection of fluids under or around the sensor. Prevent the risk
of failure due to build-up of dirt, turning-chips, or other material under the sensor(s) or the associated hardware. Give
special consideration to joints between sensors to ensure that foreign material does not migrate under or into the sensor.
Immediately repair or replace any damage (for example, cuts, tears, wear, or punctures) to the outer insulating jacket of
the interconnect cable (in the presence of fluids) or to any part of the exterior of the sensor. Ingress of material (including
dirt particles, insects, fluid, moisture, or turning-chips) which may be present near the mat can cause the sensor to
corrode or to lose its sensitivity.
Routinely inspect and test the sensor(s) per the manufacturer’s recommendations. Care must be taken not to exceed
operational specifications (for example, the maximum number of switching operations).
Securely mount the sensor(s) to prevent inadvertent movement (creeping) or unauthorized removal. Methods include (but
are not limited to) secured edging or trim, tamper-resistant or one-way fasteners, and recessed flooring or mounting
surface, in addition to the size and weight of large mats.
Install the sensor(s) to minimize tripping hazards (particularly towards the hazard). A tripping hazard may exist when the
difference in height of an adjacent horizontal surface is 4 mm (1/8 in) or more. Minimize tripping hazards at joints,
junctions, edges, and when additional coverings are used. Methods include a ground-flush installation of the sensor, or a
ramp that does not exceed 20° from horizontal. Use contrasting colors or markings to identify ramps and edges.
Size and position the safety mat system so that persons cannot enter the hazardous area without being detected, and can
not reach the hazard before the hazardous conditions have ceased. Additional guards or safeguarding devices may be
required to ensure that exposure to the hazard(s) is not possible by reaching over, under or around the device’s sensing
surface.
Take into account the possibility of easily stepping over the sensing surface without being detected. ANSI and international
standards require a minimum depth of field of the sensor surface (the smallest distance between the edge of the mat and
hazard) to be between 750 mm to 1200 mm (30 in to 48 in), depending on the application and the relevant standard.
Prevent the possibility of stepping on machine supports or other physical objects to bypass or climb over the sensor.
MAX1524 and MAX2324 Safety Mat Monitoring Modules
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P/N 122366 Rev. B
