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Product Description

The Model 268 Opto Isolation Module provides a communications link that has no electrical connections from one port to the other. Isolation is an important consideration if a system uses different power sources, has noisy signals or must operate at different ground potentials.

In a data logging or acquisition system the Model 268 protects against ground loops between the system controller and monitoring devices. These ground loops create offset voltages which result in reducing the system's noise immunity. A non-isolated path allows RF noise and voltage spikes to appear on the controllers data lines. When this happens the likelihood of data errors and system faults increase.

The 268 insures against these problems while providing full duplex, optically isolated signal paths for data, TD and RD, and a control signal pair selected by internal jumpers (CTS, RTS, DCD, or DTR). In addition to opto isolation, the Model 268 incorporates micro power DC to DC converters that generate the necessary operating voltages. There are two sets of these circuits, one for each port. The Model 268 will operate even if only TD and RD are connected. The DCE port is implemented with a DB25 male connector while the DTE port uses a female DB25 connector. The case is fabricated from aluminum and is not connected to either port.

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