Long range proximity (prox) readers have a read range from three feet to over three hundred feet depending on the system. Long range prox readers requires special prox cards or tags and prox readers. Long range prox cards are used to tag vehicles, assets, and heavy equipment so they can be tracked as they pass a specific point. The long range prox reader systems are divided into two categories, active and passive.
Active System
The active system has a prox card
reader that is strategically located
to receive a signal sent by the active tag, similar
to a radio receiver. The active tag contains
a miniature long life battery. The active tag,
continuously sends a coded pulse similar to a
radio transmitter. The long range reader receives
this coded pulse, converts it to a weigand signal
and sends it to the controller which makes a
go, no go, decision. The active tag is more reliable
then a passive and has a range of 300 feet. The
range of the signal can be adjusted from 300
feet to as little as 6 feet by a computer program
The direction of the signal can be controlled
by directional antennas. This feature makes this
product perfect for asset control to avoid theft
of high risk inventory or assets. Various styles
of tags are available for these applications.
Tag life is 5 plus years depending on the pulse
rate. Tri-Cor stocks AAID active long range readers
in stock. To learn more about this product go
to the Vuance page.
Passive System
The passive system has a prox card reader that
is similar to a transceiver. The reader is continuously
transmitting a signal in oval pattern approximately
6 feet wide by 12 feet long and then receives
a return signal from a passive tag. The passive
tag does not contain a battery, but receives
power from the prox card reader transmission
when it enters this zone. The passive tag
stores this energy in an electronic circuit
until it has ample power to return a coded
pulse to the prox card reader. This coded pulse
is then converted to a weigand signal and
sends it to a controller which makes a go,
no go decision. The range of a passive system
is limited to nine to twelve feet. The passive
system's technology requires accurate alignment
of the prox reader and the tag. Luxury car
windshields contain a metal film that may reduce
the range considerably so a alternative exterior
tag mounted to the vehicles grill may be required.
The passive systems performs best where a majority
of traffic are automobiles passing through a
restricted lanes such as public parking garages.
Tri-Cor stocks AWID passive long range readers
in stock. To learn more about this product go
to the AWID page.
Selecting a System
The choice between the two technologies is application
driven. The active system serves best in applications
with varied vehicles such as trucks, cars,
step vans are using the same entrance. The
passive system serves better where passenger
cars are entering though a controlled lane
of traffic, such as an entrance to a condominium.
Call a Tri-Cor customer technician to discuss
your application today.
Manufacturers Tri-Cor stocks both the passive and active long range readers. To learn more about the products of each the AWID page for a passive system and the Vuance for the active system.
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