Protect - Safeguarding Your Assets From All Elements
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The world of data communication is busy, even noisy. Industrial communication systems, such as balanced RS-485 / RS-422, often require transmission between multiple devices over long distances. While having many devices communicating with each other on the same twisted-pair cable is robust and cost-effective, it also introduces two major challenges: 1) because of the long distances and the surrounding electrical devices/equipment, RS-485 / RS-422 networks are often exposed to electrical noises, remote lightning, and line surges, which can cause transient voltage to run across the serial communication system and the valuable equipment; 2) because multiple devices (nodes) are connected, the ground potential at different nodes could be different, which can cause ground currents to flow through “the path of least resistance” via either the common earth ground or the ground wire.
Both voltage and current surges can cause serious damage to valuable, mission-critical equipment such as computers, PLCs, and industrial manufacturing and data processing equipment; these surges can even endanger human lives. Ground loop problems also exist on unbalanced signals that rely on the ground pin being zero volts, such as RS-232 and USB.
There are a few methods of voltage and current surge protection in the industry, and the most effective are Optical Isolators and Surge Protectors:
Optical Isolators
An optical isolator (or opto-isolator) is used to block high voltages and transients so that a surge in one part of the system will not disrupt or destroy other parts. Optical isolation uses an LED (Light Emitting Device) and a photosensitive transistor to transfer data across the isolation barrier - typically an air gap; in other words, data is transmitted using light instead of electrical signals, so there is no physical connections between the grounds and the data lines, thus removing the ground loop problems and effectively preventing electrical surges and spikes from destroying other parts of the system. Furthermore, because optical isolation uses light to transmit data across the isolation barrier, it also gains the advantage of immunity from electrical- and magnetic-field interference. This makes optical isolation an effective solution in industrial areas where strong electric or magnetic fields could be present.
Surge Protectors
The main function of a surge protector is to limit the voltage introduced to an electrical device by either blocking or shorting to ground any voltages above a safe threshold. Surge protectors are mainly used for protecting power and data lines against electrical surges and spikes, including those caused by lightning. However, it is important to note that solely relying on surge protectors could be insufficient or even do more damage than good, as in the cases of improperly installed or poorly selected surge protectors. In many applications, surge protectors are used in conjunction with optical isolators to provide much more effective protection.
Optical Isolators
From 3-wire to 7-wire RS-232 isolators, 2-wire RS-485 to 4-wire RS-422 isolators, and USB isolators to USB / RS-232 / RS-485 / RS-422 optically isolated converters, CommFront has all the optical isolation devices to protect your assets from unexpected events. If off-the-shelf product does not provide enough security for you, we can even tailor-make the devices, which are customizable right down to the nuts and bolts.
| RS-232 | RS-485 / RS-422 | USB |
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Model: CVT-232A-3 Description: RS232 Opto-Isolator (3-Wire / Industrial / Port-Powered) Key Features: |
Model: RPT-485_422-4 Description: RS485 / RS422 Isolator / Repeater / Converter (Industrial) Key Features:
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Model: USB-ISO-3 Description: USB Isolator (Industrial) Key Features: |
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Model: CVT-232B-3 Key Features: |
Model: HUB-485-4 Key Features: |
Model: USB-Serial-3 Key Features: |
Surge Protectors
Data networks are often exposed to high-voltage and/or high-current electrical surges and spikes, including those caused by lightning. Our passive, rugged, industrial-grade surge protectors are designed for direct indus- trial DIN-rail mounting and they come with two (2) or three (3) stages of surge protection – gas discharge tube, protection resistors, and Transient Voltage Suppressor (TVS) - for maximum protection. From 2-wire RS-485, 4-wire RS-422 / RS-485, to 10 / 100 / 1000M Ethernet, CommFront’s surge protectors safeguard your data lines and provide you with peace of mind.
| 2-Wire RS-485 | 4-Wire RS-485 / RS-422 | 10 / 100 / 1000M Ethernet |
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Model: SPD-485-1 Key Features: |
Model: SPD-422-1 Key Features:
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Model: SPD-ETH-1 Key Features: |
The Products – Isolators & Protectors
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| CVT-232A-3 | CVT-232A-4 | CVT-232B-3 | RPT-232-3 | CVT-485-3 | CVT-422-3 |
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| CVT-485_422-3 | CVT-485_422-3(25) | CVT-485_422-4 | RPT-485_422-4 | HUB-485-4 | USB-Serial-3 |
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| USB-ISO-3 | SPD-485-1 | SPD-422-1 | SPD-ETH-1 |
Key Features
- Rugged industrial grade.
- Built for harsh environments and interfacing with mission-critical equipment.
- Protects your expensive equipment from potential harms including ground loops, transient surges, lightning, and spikes.
- Options of in-line or DIN-rail / wall mounting.
| Model | Description |
|---|---|
| CVT-232A-3 | RS232 Opto-Isolator (3-Wire / Industrial / Port-Powered) |
| CVT-232A-4 | High-Speed RS232 Isolator (3-wire / Industrial / 5VDC-Powered) |
| CVT-232B-3 | RS232 Opto-Isolator (7-Wire / Industrial / Port-Powered) |
| RPT-232-3 | Opto-Isolated RS232 Repeater (Industrial / Port-Powered) |
| CVT-485-3 | Opto-Isolated RS232 to RS485 Converter (Industrial / Port-Powered) |
| CVT-422-3 | Opto-Isolated RS232 to RS422 Converter (Industrial / Port-Powered) |
| CVT-485_422-3 | Opto-Isolated RS232 to RS485 / RS422 Converter (Industrial / Port-Powered) |
| CVT-485_422-3(25) | 25-pin Opto-Isolated RS232 to RS485 / RS422 Converter (Industrial / Port-Powered) |
| CVT-485_422-4 | High-Speed Opto-Isolated RS232 to RS485 / RS422 Converter (Industrial / Externally-Powered) |
| RPT-485_422-4 | RS485 / RS422 Isolator / Repeater / Converter (Industrial) |
| HUB-485-4 | Opto-Isolated RS485 Hub / Splitter (Industrial) |
| USB-SERIAL-3 | Opto-Isolated USB to RS232 / RS485 / RS422 Converter (Industrial / Port-Powered) |
| USB-ISO-3 | USB Isolator (Industrial) |
| SPD-485-1 | 2-Wire RS-485 Surge Protector (Industrial / Passive) |
| SPD-422-1 | 4-Wire RS-422 / RS-485 Surge Protector (Industrial / Passive) |
| SPD-ETH-1 | 10 / 100 / 1000M Ethernet Surge Protector (Industrial / Passive) |