A facilities management company required a practical and cost-effective method to add new pressure monitoring points to an existing HVAC chilled water system and integrate them into their Building Management System (BMS). The chosen solution utilized a wireless pressure transmitter and receiver system, which successfully addressed the challenges of prohibitive cabling costs and difficult installation locations. This approach not only simplified the installation process but also provided reliable and accurate pressure data for enhanced system control and efficiency.
- Eliminate Cabling Costs: The wireless system offers a significant cost saving by dispensing with the need for expensive and labor-intensive cable runs from the sensor to the control panel.
- Outdoor Installation: The pressure transmitter is housed in a rugged, IP68 rated enclosure, making it perfectly suitable for installation in outdoor environments or demanding plant room conditions.
- Seamless BMS Integration: The receiver features a standard, user-selectable 4-20mA or 1-5Vdc analogue output, allowing for straightforward and trouble-free connection to any standard BMS input.
- Simple ‘Plug and Play’ Setup: The transmitter and receiver are designed for easy pairing via internal DIL switches, enabling a quick and simple ‘out of the box’ installation without the need for complex software configuration.
- Reliable Long-Range Communication: The system operates on the 2.4 GHz frequency band, providing a robust communication link with a line-of-sight range of up to 500 meters, ensuring dependable data transmission across large sites.
A facilities management company was seeking a solution for monitoring chilled water pressure within a large-scale HVAC system. The primary challenge was the difficulty and expense associated with running new cables to the required monitoring points. The data from these new measurement points needed to be integrated into their existing Building Management System (BMS) to provide a more comprehensive overview of the HVAC system’s performance. The key requirements were for a wireless pressure transmitter that could be installed outdoors and reliably transmit pressure readings back to a central receiver connected to the BMS. The required pressure measurement range was 0 to 10 bar gauge.
To meet these requirements, a wireless pressure sensing solution was proposed, consisting of an IWPT series wireless pressure transducer and an IWR-1 single-channel wireless receiver. This combination provides a cost-effective alternative to traditional hard-wired sensors, completely eliminating the need for expensive and disruptive cable installations.
The IWPT series transducer is specifically designed for this type of application, featuring a robust 316 stainless steel housing and a piezo-resistive ceramic sensor, ensuring excellent compatibility with the chilled water media. Its IP68 rated enclosure makes it suitable for outdoor installation, addressing the customer’s direct question. The transducer operates on the 2.4 GHz ISM band and is designed for simple pairing with the receiver using a DIL switch, creating a ‘plug and play’ setup. With a battery life of up to five years at a 10-second transmission rate, maintenance is kept to a minimum.
The IWR-1 receiver was the ideal counterpart for this application. It is a single-channel unit designed to receive data from a dedicated wireless transmitter. The receiver provides a direct interface to the BMS through its user-selectable 4-20mA or 1-5Vdc analogue output. This allows for seamless integration into the existing control and monitoring infrastructure. The system boasts a line-of-sight transmission range of up to 500 meters with the standard antennas, more than sufficient for most HVAC plant room and building monitoring scenarios. Furthermore, the IWR-1 receiver includes a 5A-rated changeover contact relay, which can be configured for alarm functions, such as indicating if the pressure goes outside of set limits, if the signal is lost, or if the transmitter battery is low, providing an extra layer of system security. The entire system offers an end-to-end accuracy of better than ±0.25% of the full-scale reading, ensuring the BMS receives reliable and precise data for effective HVAC management.
IWPT Wireless Pressure Sensor with IWR-1 Single Channel Receiver
- Part No: IWPT-G1002-00, IWR-1, IANT-3
- Wireless Transmitters: Pressure Sensor
- Process Connection: 1/4 BSP male
- Pressure Ranges (bar): 10 bar g
- Wireless Receivers: Single channel 1-5V or 4-20 mA output
- Optional Extras: 3dBI receiver mount antenna for increased wireless range