Single-Channel A/B Switch provides automatic backup.

Press Release Summary:

Controlled via front-panel pushbutton or DB9 female serial interface Remote port on rear of unit, PathWay Model 4133 enables sharing single port interface device connected to COMMON port among 2 other devices connected to A and B ports. Switch monitors data activity on port A and automatically switches to B position if activity is lost for duration of set delay time. Upon power loss, this single-channel DB25 A/B switch maintains last set position and continues to pass data.

Original Press Release:

Model 4133 A/B Switch Provides Reliable Automatic Backup when Primary Line Fails

Electro Standards Laboratories, Cranston, RI, announces the Model 4133 single-channel DB25 A/B switch with auto fallback and RS232 remote control. The PathWay Model 4133 enables sharing a single port interface device connected to the COMMON port among two other devices connected to the A and B ports.

Model 4133 is controlled locally via a front-panel pushbutton or remotely via the DB9 female serial interface Remote port located on the rear of the unit. The front-panel LED display indicates the switch position, switch mode and power status.

This switch monitors data activity on port A. If the unit is in the A position and activity is lost for the duration of the set delay time, the unit automatically switches to the B position. The unit will remain in the B position until commanded to switch to the A position either manually or remotely.

The Model 4133 maintains the last set position on power loss and continues to pass data. The remote RS232 ASCII commands allow the user to control the switch position, lockout the front panel operations, change modes, set the delay time and obtain switch status. The remote port contact closure status on pins 6, 7, and 8 provide dry contact logic to obtain the present switch position. The automatic switching is based on RS232 TD and RD activity on Port A. For convenience, the front panel LED’s display switch position, switch mode, and power status.

The Model 4133 is packaged in a slim desktop style enclosure. The dimensions are 7.75” W x 7.25” D x 2.0” H (19.7 x 18.4 x 5.1 cm) and the unit weighs approximately 2.5 lbs. (1.13 Kg). The switch is available for export worldwide.

This switch is supplied with a UL approved 100VAC/240VAC, 50Hz/60Hz wall mount power module that supplies 12VDC, 500mA to the unit. Optionally available is a wide range power module (Catalog No. 517277). This power supply is a CE, RoHS, and UL listed table mount unit, 100VAC, 240VAC, 50Hz/60Hz in place of the standard power module. This power supply features an IEC 60320 C14 inlet and is ideal for international applications.

For more information on the Model 4133, visit Electro Standards has a staff of knowledgeable sales engineers to answer any application questions, 401-943-1164 or

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