Installation] Installation of FIX800 O2 H2S EX closed space gas concentration meter at Incheon City sewage treatment plant, installation of temperature and humidity transmitter for work environment analysis, and integrated monitoring through FIX AP

Project Overview

This installation case documents a multi-phase upgrade project carried out at two geographically separate municipal sewage treatment facilities in Incheon City. Both sites had previously been equipped with the FIX800 3GAS fixed multi-gas detector — simultaneously monitoring O₂, H₂S, and EX (combustible gas/LEL) — along with the FIX-DS 3CH entry-point status display board. The project objectives were: (1) to integrate both dispersed monitoring points into a single centralized wireless monitoring platform using the newly launched FIX AP IoT access point, and (2) to supplement existing gas monitoring with temperature and humidity transmitters in response to growing regulatory attention to workplace environmental conditions.

Summary of Work Completed

1. FIX800 O₂ / H₂S / EX fixed gas detectors and FIX-DS 3CH entry-point status display boards already installed at two separate Incheon sewage treatment facilities.
2. Simultaneous monitoring of both geographically separated sites required from a single control room.
3. FIX AP wireless monitoring hardware installed at both sites to enable centralized cloud-based management.
4. Temperature and humidity transmitters additionally installed and integrated into the same monitoring platform to address workplace thermal environment compliance requirements.

Conclusion: Wireless monitoring hardware successfully connected to existing FIX800 installations at both sites; temperature and humidity instrumentation installed; operator training completed.

PART 1 | FIX AP Product Launch and Site Survey

This project involved a somewhat unusual site configuration. Both facilities already had the FIX800 3GAS fixed multi-gas detector — capable of simultaneously measuring the three gases most commonly generated in sewage treatment confined spaces (O₂, H₂S, and EX) — along with entry-point status display boards, installed at two separate locations within the Incheon municipal water reclamation network.

The FIX AP — an integrated environmental wireless monitoring system — was launched in February of the project year, developed in part in direct response to requirements of this nature. Upon launch, the team proceeded to site to conduct a communications assessment, as Wi-Fi or wired LAN availability in the immediate vicinity of each planned FIX AP installation point is the most critical prerequisite for deployment. Dedicated Wi-Fi routers had been pre-positioned adjacent to each planned FIX AP installation point by the facility operator, facilitating smooth project execution.

Because the existing FIX800 units at each site were already connected in a 1:1 configuration with their respective display boards via RS-485, the FIX AP's 4-20mA analog input terminals were selected as the interface method for this project. This approach leverages the FIX800's inherent capability to simultaneously output both digital RS-485 communication and analog 4-20mA signals without requiring any additional hardware options — and equally highlights the FIX AP's versatility in accepting both signal types.

PART 2 | FIX AP Installation and Wiring

The FIX AP features six 4-20mA input channels with integrated 24V power output terminals (positive and negative), making it compatible with 2-wire, 3-wire, and 4-wire transmitter configurations of any measurement type. Channels 1, 2, and 3 were assigned to the three gas sensor signals from the FIX800 (O₂, H₂S, EX respectively), leaving three channels available — at which point the addition of a temperature and humidity transmitter was proposed and accepted by the client.

The existing conduit run was cut and a junction box was installed mid-run to accommodate the new 4-20mA signal wiring. Routing all required conductors through the existing conduit — three 4-20mA signal wires for the FIX800, one for temperature, one for humidity, and one common negative (six conductors total) — proved impractical, necessitating a new dedicated cable run. Installation at both sites was completed within a single working day, as the two facilities were located in close proximity. The FIX AP and gas monitoring work were executed first; the temperature and humidity transmitter installation was carried out subsequently in a separate visit, as it had been added to scope mid-project and required additional procurement and budget authorization.

Summary of completed work:

• FIX AP installation and network commissioning — 2 sites
• Temperature and humidity transmitter installation and network commissioning — 2 sites

PART 3 | Cloud Service Configuration, Commissioning, and Operator Training

Following the completion of installations at both sites, operator training on the cloud monitoring service was conducted in the facility's control room — physically separate from the measurement locations — to demonstrate the practical value of remote visibility. Training covered three topics sequentially: real-time gas concentration monitoring, historical data management, and site-specific device configuration for each of the two installed locations. The site manager accessed the mobile web monitoring interface on a personal device during the training session.

The cloud monitoring platform is entirely browser-based and requires no dedicated application or software installation. Multiple authorized users may access the system simultaneously from any device to monitor real-time conditions at all registered installation points.

PART 4 | Conclusion — Remote Monitoring via FIX AP and Universal 4-20mA Transmitter Compatibility

This project demonstrated that previously installed fixed gas detectors can be successfully upgraded to wireless cloud monitoring capability without replacing existing hardware. The ability to simultaneously monitor not only gas concentrations but also additional environmental parameters — temperature and humidity — from a single integrated platform represents a significant operational advantage for facilities managing confined-space entry programs. Future development roadmap includes RS-485-only device connectivity updates and the simultaneous use of status display boards, gas detectors, and FIX AP as a fully integrated three-component system.

Installation Specifications