Wintriss Shadow 8, Руководство пользователя

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Shadow 8 User Manual 1139300
Installation and Checkout 2-27
Preventing Cross Talk between Two Sets of Shadow
8 Heads
Normally, the phototransistors in the Shadow 8 receiver do not respond to other light sources,
accepting only infrared light pulses of a certain duration in proper sequence. However, in
cases where two sets of Shadow 8s are located in close proximity to each other, the LEDs
from the transmitter of one pair may be detected by the phototransistors in the receiver of the
other pair. This is called “cross talk.”
Cross talk may occur when one pair of Shadow 8s is mounted horizontally next to a vertical
pair to detect an operator between the vertical set and the pinch point. Cross talk may also
occur when guarded machines are close together, the light from the transmitter on one press
being detected by the receiver on the other press.
There are several ways to prevent cross talk:
•
Insert a barrier of some type, such as a blind, between the two sets of Shadow 8 heads.
Make sure that the barrier runs all the way from the transmitter to the receiver.
•
Reverse the position of the transmitter and receiver on the second press, as shown in
Figure 2-17.
•
Set different scan codes for adjacent pairs of light curtains on the option switches on Main
Receiver and Transmitter (see Setting Scan Codes (Receiver Switch 3, Transmitter Switch
1), page 2-47).
•
Reduce the scanning range to its lower setting (see Setting Scanning Range (Receiver
Switch 6), page 2-48).
These solutions can be used singly or in combination.
Figure 2-17. Reversing Transmitters (TX) and Receivers (RX) to Prevent Cross Talk