Electricity + Control October 2017

Launch of turbidimeters Prei Instrumentation proudly introduces the Hach TU5 Series family of turbidimeters for drinking and high purity water turbidity measure- ment, for online as well as laboratory use. Not only does Hach use the latest ISO standard (DIN EN ISO 7027) for laser technology Nephlerometric measurement, but Hach has de- veloped a newstandard, HachMethod 10258which has been approved and adopted by the USEPA as a standard for the measurement of Tur- bidity.The HachTU5 Series of turbidimeters uses groundbreaking 360º x 90º detection technology employing a patented optical design that sees more of your sample than any other turbidity meter, delivering the best low level precision and sensitivity while minimising variability from test to test. The turbidimeter measures turbidity by directing a laser into a sample to scatter off suspended particles.The light that is scattered at 90º from the incident beam is reflected through a conical mirror in a 360º ring around the sample before it is captured by a de- tector.The amount of light scattered is proportional to the turbidity of the sample. If the turbidity of the sample is negligible, little light will be scattered and detected by the photocell and the turbidity reading will be low. High turbidity, on the other hand, will cause a high level of light scattering and result in a high reading. Prognosys monitors

your TU5 series online instrument, proactively alerting you to main- tenance needs before your measurement becomes questionable. A Hach Service Agreement protects your investment and helps ensure that you stay in compliance and on budget. Prei Instrumentation is the South African distributor for Hach online liquid analysis equipment. Hach has been the market leader in turbidity measurement since Clifford Hach introduced the first Continuous Read turbidimeter in 1957. Enquiries: Email steve.herbst@prei.co.za

Optic principle.

360º x 90º detection technology.

Accurate echo

sor emits an ultrasonic pulse train and receives the echoes reflected. The electronics evaluates the echo time of the pulses and determines the level. The compact evaluating electronics is mounted on the unit. For remote transmission, a norm signal out- put and for monitoring purposes, a relay contact is available. For programming and for local dis- play, the units may be delivered with an optional pluggable programming unit with LCD display. The sensors have a total beam angle of 5°-7° at -3 dB. This ensures a reliable measurement in nar- row silos with uneven side walls as well as in pro- cess tanks with various protruding objects. Further- more, as a result of the narrow beam angle − the emitted ultrasonic signals focus and penetrate gases, vapour and foam. Enquiries:Tel. +27 (0) 10 595 1831 or email sales@instrotech.co.za

KOBOLD, represented locally by Instrotech , has on offer an ultrasonic level meter, model NUS-4, to be used for non-contact, continuous level and volume measurement in vessels or for flow measurement in open channels. Level measurement technology based on the non-contacting ultrasonic principle is especially suited for sticky or abrasive media and applications where, for any reason, no physical contact can be es- tablished to the surface of the material to be meas- ured. Such reasons may include corrosive attack by the process medium against the measuring device material (acids), possible contamination (sewage) or particles of the process medium adhering to the measuring device (adhesive materials). The ultrasonic level metering technology is based on the principle of measuring the time required for the ultrasound pulses to make a round trip from the sensor to the level to be measured and back.The sen-

10 Electricity + Control

OCTOBER 2017