Amplifier heating monitoring for communication equipment using hexagonal bolt temperature sensing probes.
Comlab based at Ittigen in Switzerland is a specialist provider of radio communication equipment. Its digital multi-band repeaters are designed to ensure seamless mobile communication and radio reception in challenging environments such as road and railway tunnels, mines and other difficult to service areas such as mass transit stations, shopping centres and large commercial buildings. With both standard and user-customised products available that must operate with optimal performance and highest reliability, they have chosen Variohm EuroSensor ETP-SP-PT platinum series hexagonal bolt temperature sensors as a convenient and cost-effective way of monitoring the instrument’s amplifier heating characteristics.
Each Comlab multi-band repeater typically includes several amplifier stages and associated sensors. As the Variohm hexagonal bolt probe is integrated into its own fastening screw, there is no need for an additional clamping assembly that would be required for a regular temperature probe. There is also a distinct and ideal advantage in the way that Comlab design engineers applied the component as the heat transfer directed through the screw into the sensing element is fully optimised with minimal external temperature disturbance.
The ETP-SP-PT is part of a family of temperature probes based on the industry-standard PT100 and PT1000 thermistors that are aimed at a broad range of industrial, automotive and scientific applications for precision temperature measurement. As well as the hexagonal bolt version with a choice M6, M7 and M8 thread options, a ring terminal probe is offered for hole clearance diameters between M4 and M8.
Standard probes for the PT100 and PT1000 thermistor cover a temperature range from -40 to +250C. The hexagonal bolt and ring terminal designs are also available as lower cost NTC versions with a 10K3A1B sensing element for a lower, -40 to +125C, temperature range. NTC versions are also available as probes housed in 4 mm diameter PTFE or 5 mm diameter brass.
A wide choice of options for both PTC and NTC versions include different thread sizes for the hexagonal bolt model, alternative ring terminal mount diameters, alternative housing diameter and length for the cylindrical probes, and other lead lengths or connector terminations. Fully connectorised versions with M10 threaded connections are also available.