VP-TX-120 Series

Gas Sensor Transmitters


Field Wiring
Block Diagram
Series Part Numbers

The VP-TX-120 Series of Gas Sensor/Transmitters are the inexpensive alternative to gas detection and environment monitoring. The combination of analog 4-20 mA output and the RS-485 digital port makes this unit the ideal choice to connect to analog controllers and digital PLC's. The various Gas Sensors available provide accurate level readings with a life spans of up to 2 years (for electrochemical sensors) and up to 7 years (for solid state sensors) under normal applications.

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The on board temperature sensor and %RH (Humidity) sensor can be read directly from the RS-485 port or with the LCD display which is internally mounted. The user interface consists of a Status LED, LCD and three pushbuttons. The Status LED indicates OK, LOW, MID, HIGH Alarm. The three pushbuttons and internal LCD provide a convenient calibration method. There are NO potentiometers, all programming and calibration is performed digitally from the user interface. The compact ABS enclosure is rated for IP66 of IEC 529 and NEMA 1,2,4,4x,12 and 13. The interior is EMI/RFI shielded with a nickel conductive coating. For installation convenience, the VP-TX-120-CO comes complete with mounting hardware already installed.

Standard Features

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Transmitter Layout

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The VP-TX-120 has two printed circuit card assemblies:
1. The main pcb has the LCD, User Interface components, relay. RS485 Rj45 jacks, and the field wiring terminal blocks. This module is common to all the various sensor types.
2. The sensor module is mounted on the door for the enclosure and has the gas sensor, temperature sensor, humidity sensor, pwoer and status LEDs.

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Field Wiring for all VP-TX-120 Series Transmitters

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Block Diagram for all VP-TX-120 Series Transmitters

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Transmitter Part Numbers

Sensor Type Description Typical Gas Ranges Part No   Ordering
Solid State Gas Sensor / Transmitter for CO, Methane, Ammonia, Propane, Freon 0 - 400 PPM CO VP-TX-120-SS   Contact Us
Pellistor Gas Sensor / Transmitter for CH4, Propane 0 - 100 %LEL VP-TX-120-CH4   Contact Us
Electrochemical Gas Sensor / Transmitter CO (Carbon Monoxide) 0 - 1000 PPM VP-TX-120-CO   Contact Us
Electrochemical Gas Sensor / Transmitter NH3 (Ammonia) 0 - 100 PPM VP-TX-120-NH3   Contact Us
Electrochemical Gas Sensor / Transmitter O2 (Oxygen) 0 - 25.0 %VOL VP-TX-120-O2   Contact Us
Electrochemical Gas Sensor / Transmitter H2S (Hydrogen Sulphide) 0 - 100 PPM VP-TX-120-H2S   Contact Us

NOTE: Other gas ranges are available upon request

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