WebRelay Users Manual
2.5.3 Dual WebRelay Devices (no computer required)
This configuration is used to control devices remotely without a web browser, or to extend a digital signal
to a remote location on the network. A control voltage applied to one WebRelay controls the relay
contacts of another WebRelay at a remote location.
This configuration has may uses. It allows a switch to be placed a long distance from the device that it
controls.
For security applications, the switch in the example could be replaced with a sensor, and the device to
be controlled could be a buzzer or chime. A business owner, for example, could set up a sensor at
his/her office and a chime at his/her home. The chime at the home would announce each time the
sensor detects entry to the office (which could be miles away). When the chime indicates an office entry
late at night, the business owner can take appropriate action.
Another way this configuration is useful is to extend the output of a PLC (Programmable Logic
Controller) in a factory to control a motor in another building. The output of the PLC is connected to the
input of one WebRelay, and the motor is connected to the relay contacts of a second WebRelay. This
allows any PLC to control devices across an IP network.
Xytronix Research & Design, Inc.
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