TransCore encompass 4, Руководство пользователя

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Chapter 4 Installing the Encompass 4 Reader
TransCore Proprietary
4-59
and Black pair. Note that the black of the yellow/black is not connected. The third pair of the three-
pair cable can be used for a spare in the event either of the other two pair are damaged or fail. The
cable shield should be tied to a single-point Earth Ground on the controller end of the cable. Refer
to Figure 46.
Warning!
Do not cut the RS–232 red/black wires. If you cut the wires, you may not be able to use them in
the future for testing, setting frequency, or adding additional functions.
Connecting Sense Input and Sense Output Circuits
The Encompass 4 Reader has two sense input circuits and three sense output circuits available. The sense
input circuits can be used to notify the Encompass 4 Reader of external events and are designed to be
connected to a free-of-voltage dry contact. Sense output circuits are single-pole, double-throw relays that
provide normally closed (NC) and normally open (NO) dry contacts. The relay contacts are rated at 42.2V
AC peak (30 Vrms) or 60V DC at 1 A maximum. If controlling an external gate or device requiring high
current, an isolation transformer is required.
The following sections provide information to connect the sense input and sense output circuits.
Sense Input Circuits
The Encompass 4 Reader supports two sense inputs – sense input0 and sense input1– which requires
two sense input lines for each loop sense or a total of four sense input connections. Sense input0 is the
presence detection device line and is used to control RF power. As shown in Figure 47 , sense input0
is through the red/green wire pair on the I/O pigtail. The Encompass 4 Reader expects the sense input0
circuit to close when a vehicle is present (i.e., a NO condition). The minimum presence true period is fixed
at 0 ms, which indicates that no delay occurs in closing the circuit when a vehicle is present.
Sense input1 allows the Encompass 4 Reader to monitor the status of a peripheral device. The host
computer can then check the status by polling the Encompass 4 Reader.
Figure 46 Wiegand Cable Extension Diagram