Device Showcase – Wireless Flex Transmitters for Temperature and Humidity Measurement

We’ve developed over 500 different measurement devices capable of wirelessly measuring various parameters in diverse operational environments. In this Device Showcases series, we showcase one measuring device each month, detailing what it measures, the unique features that set it apart, and most importantly—how it simplifies your daily measurements.

In Spotlight: Flex Transmitter Series

The Flex product line is a weatherproof transmitter series offering multiple input options for various measurement and monitoring needs. These universal devices are suitable for a range of applications, including environmental monitoring in construction, process industries, and commercial kitchens. The Flex product line consists of 10 different measurement devices designed for measuring environmental temperature and relative humidity.

Top 3 Features of Flex Transmitters

1. Wireless Capability – Easy Installation Without Wiring
2. Durability – Long Battery Life in Demanding Conditions
3. Flexibility – Choose from Five Measurement Heads and Two Radio Technologies (LoRaWAN and Sky)

Wireless Capability – Easy Installation Without Wiring

Flex devices prove to be an excellent option when the goal is to eliminate wiring between various spaces. Their wireless functionality removes the need to breach boundaries for data transfers. Devices can be easily installed in enclosed spaces where running wiring may be difficult or expensive. The LoraWAN and Sky technologies ensure reliable coverage even in challenging locations such as basements or cold storage.

Durability – Long Battery Life in Demanding Conditions

Flex transmitters are particularly suitable for measuring slow changes when extremely fast response times are not crucial. These robust devices excel in demanding conditions, making them ideal for applications like measuring temperature and humidity in precisely defined conditions within, for example, freezer cabinets and environmental chambers.

The devices are configured based on how frequently updated measurement data is desired by the customer. The transmission interval affects battery life and coverage.

Flexibility – Choose from Five Measurement Heads and Two Radio Technologies

The Flex product line is divided into two series based on the radio technology used in the devices.

• Flex-Sky series devices use Nokeval’s proprietary modulation based on LoRa technology.
• Flex2-LWEU series devices, on the other hand, operate using LoRaWAN technology.

Each series has the same measurement module in every device version, with only the radio head changing based on whether it’s a Flex device using Sky technology or a Flex2 device using LoRaWAN technology. The transmitter’s two-part structure allows seamless calibration changes to the measurement module.

When to Choose Flex2-LWEU Series and When to Choose Flex-Sky Series?

Flex-Sky Series – Convenient for Local Use with Modbus Support

Flex-Sky devices are a good choice when wirelessly transmitting individual signals from one location to another is desired. These devices can be used in factories with a local receiver and the customer’s own Modbus-based data acquisition system. Modbus support is necessary for integrating devices into, for example, building automation systems.

Flex-Sky devices operating within an internal network can optionally be connected to an external service, using a Cell2 base station.

Flex2-LWEU Series – Hub Base Station and NSnappy Platform

Flex2-LWEU device measurement data always passes through some network service. Unlike Flex-Sky devices, Flex2 series devices cannot be used within an internal network. Flex2 devices work in conjunction with NSnappy® Hub base station, requiring this specific base station to function. Monitoring the measurement data of Flex2 series devices is seamless through the NSnappy® service, which operates on a monthly subscription basis. We recommend its continuous usage for optimal results. Alternatively, it’s possible to connect Flex2 devices to the customer’s own cloud service.

Differences Among the 10 Flex Product Line Measurement Devices

Both the Flex-Sky and Flex2-LWEU series have five equivalent measurement devices, with the radio head changing based on the series. The table below allows you to compare these devices with each other.

Measuring device	What does the device measure?	Why choose this version?
Flex2-ES LWEU/LWNA and Flex-Sky-ES	Measures temperature with an external sensor connected to the spring connector inside the transmitter	When an external sensor is required, with infrequent replacement: - When exceeding or falling below the specifications of the measuring device, for example, the measurement sensor needs to be placed in a hotter location than the transmitter's own temperature endurance. - When measurements take place in an area with no radio coverage, an external sensor can be placed inside, for instance, a refrigerator, with the transmitter positioned outside. - Does not require an M12 connection. - Cable gland
Flex2-CS LWEU/LWNA and Flex-Sky-CS	Measures temperature with an external sensor	When there's a frequent need to replace an external sensor: - When exceeding or falling below the specifications of the measuring device, for example, the measurement sensor needs to be placed in a hotter location than the transmitter's own temperature endurance. - In locations with no radio coverage, an external sensor can be placed inside, for instance, a refrigerator, with the transmitter positioned outside. - Easy replacement of the sensor is facilitated by the M12 connector, which can be easily detached and swapped with another sensor. When the measuring device needs to be directly attached to the sensor, a mechanically stable package is achieved Easy to maintenance
Flex2-nSens LWEU/LWNA and Flex-Sky-nSENS-HT-EIS	Measures temperature and humidity with the Novasina nSens sensor	An excellent choice when aiming for a humidity measurement accuracy better than 1% Ideal for highly critical points requiring precise results, such as in the food industry and concrete drying measurements The sensor is highly durable
Flex2-T-RH LWEU/LWNA ja Flex-Sky-T-RH	Measures ambient temperature and relative humidity	General-purpose humidity and temperature measurement sensor. Used when an ultra-precise reading is not required (device accuracy > 1%). Ideal for temperature and humidity measurements in storage areas. Suitable for environmental chambers, such as in the food industry, to measure the durability of food under defined humidity and temperature conditions.
Flex2-T LWEU/LWNA ja Flex-Sky-T	Measures ambient temperature with an internal sensor	Perfect for measuring slow changes where rapid response time is not critical (response time: 30 minutes) When an external sensor is not needed, and there is no need to attach wires or connectors Long battery life