Fiber is a robust and inexpensive way of sending data long distances. Unfortunately, automation, access control and data acquisition hardware typically doesn’t come with a fiber interface. The serial RS-232, RS-422 and RS-485 standards are, however, practically ubiquitous in this type of equipment. Serial-to-fiber converters solve this problem. By connecting a serial interface to a serial-to-fiber converter, data can be sent hundreds or thousands of yards in electrically noisy environments without risking corruption by EMI. At the receiving end a second converter turns the optical signals back into serial for easy connection to a computer. Westward Sales carries industrial-grade serial-to-fiber converters for switching between single or multi-mode fiber and RS-232/422/485.
A serial-to-fiber converter, sometimes referred to as a “transceiver,” contains both a transmitter and a receiver. Electrical signals are converted to light and light back to electrical signals. Light is transmitted in one of two ways: single-mode and multi-mode. While single-mode offers longer range – potentially many miles - and higher bandwidth, multi-mode predominates in most industrial and commercial environments.
The effective range of RS-232 is 50' (15.2m) but RS-422 and RS-485 work over distances to 4,000' (1,200m.) Multimode fiber is often used for sending data hundreds or a few thousand feet so competes with RS-422 and RS-485. However, its big advantage is EMI immunity. As industrial environments in particular contain many sources of electrical noise, from welders and motors to transformers and switchgear, fiber has the benefit of eliminating errors.
Westward carries serial-to-fibers converters to meet a range of needs and applications. Manufactured by Antaira Technologies, these come with a 5 year warranty. Each converter is available in both multi and single-mode forms, so they pair readily with existing fiber infrastructure. All will accept either ST or SC connectors.
When all that’s needed is basic conversion functionality the STF-300C compact unit does the job. Selectable between RS232/422/485, it is available with a single mode option and also offers WDM. It comes in a metal enclosure and needs a 12V supply.
Designed for DIN-rail mounting, the STF-401C multi-mode, (optionally, single-mode) converter handles speeds from 300bps to 921kbps. It needs 9 to 48VDC and provides 15KV of ESD protection.
Fanless and DIN-rail mountable, the STF-501C industrial-grade converter incorporates 2.5 kV of isolation protection and 8 kV of ESD Protection. Front-facing LEDs indicate power, TD/RD, or fiber link problems.
With 2.5 kV of isolation protection and 8 kV of ESD Protection, the dual fiber ports and redundant dual power inputs (12 to 48VDC) make the STF-502C converter robust enough for the most challenging environments.
Serial devices are used in many industries but achieving reliable data transmission over long distances is often difficult. With a serial-to-fiber converter RS-232/422/485 data can be sent long distances without fear of corruption or error. Contact a Westward Sales product specialist for further information.