Electricity and Control April 2024

MEASUREMENT + INSTRUMENTATION : PRODUCTS + SERVICES

High-precision data loggers

The PRO 111/PRO 115 data loggers are professional handheld meters for 4-wire Pt100 probes. Any four wire Pt100 standard probe can be connected provided it is equipped with an M12 connector. The instruments have a high-precision temperature-compensated analogue front-end meter that does not add any significant error in the measurement chain and also offers life chart view ing. The devices incorporate sophisticated polynomial sensor linearisation to ensure best performance and to provide all relevant possibilities for calibration and ad justments. Both the PRO 131 and PRO 135 models are dual channel professional handheld meters for thermocouple probes. They offer configurable surface correction factors and can be set for use in combination with Senseca contact probes for enhanced measuring accuracy. The PRO 135 additionally has a data logging capability. □ ing pressure wave can cause significant problems, in cluding pipe failure. To prevent this, a long closing time is often specified. Sometimes as long as 10 to 20 minutes. This is achieved using a speed control needle valve on the level control valve. However, the needle valve is usually set very low, which makes it prone to clogging with dirt and sediment. When this happens the level control valve will not close and the reservoir overflows. Needle valves require high maintenance. Ultra Control Valves has developed a self-cleaning speed controller to solve this problem. It can accommo date a wide range of closing speeds and is reliable even without regular maintenance. This innovation marks a significant step forward in the efficient operation of level control valves. □

Senseca, formerly the GHM Group, has launched its redesigned PRO 111/PRO 115 handheld meter/ data logger for Pt100 4-wire probes as well as the PRO 131/PRO 135 data logger for thermocouple probes. Both the devices now include enhanced features. A higher quality LED screen with backlit dot matrix and clear text display make the data more easily vis ible and the data logging storage capacity provides for logging of up to one million data units. “The high-precision instruments are suitable for temperature measurement across all industries. They are robust, reliable and ergonomically designed for one handed or bench top use,” says Jan Grobler, Managing Director of Senseca South Africa.

Senseca has launched its redesigned data loggers with improved functionality.

Level control in water reservoirs

Ultra Control Valves has developed a self-cleaning

Peter Bowen of Ultra Control Valves says one of the most common applications for self-actuated control valves is in reservoir level control. At first glance the valve looks simple – exactly like the valve in a toilet cistern. Except that toilet valves are not likely to fail from cavitation.

speed controller to ensure reliable closing of level control valves.

Combatting cavitation by controlling flow rates through level control valves is a cen tral concern in water management. Here, however, Bowen looks at a common problem that arises from preventing wa ter hammer when closing reservoir control valves. Water hammer occurs when a fluid in mo

tion is forced to stop suddenly – for instance, when closing the level control valve on a reservoir. The result

20 Electricity + Control APRIL 2024