Echotel 961/962 Liquid Level Switches

The Echotel 961/962 liquid level switch makes use of unique self-diagnostics to detect malfunctions of the electronics and transducer, and also alarm the user in case of excessive electro-magnetic noise interference. This unique feature watchguards not only the performance of the switch but also the performance of other field instrumentation in the area. SIL philosophy is fully integrated into the design, resulting in a reliable and safe to use switch. With a SFF of > 90%, the 961/962 scores as one of the safest switches in the world. It can be easily integrated in SIL instrumented loops of SIL 1, 2 and 3 level depending the users’ safety system and historical experience with the technology.

The unique features of the 961/962 include adjustable time delay, “on-demand” testbuttons for the output (alarm, error, wiring, linked actuators), LED indication for alarm status, reliability condition and in case of malfunction, identification of the malfunction and separate error signal. The 961 provides a single setpoint where the 962 offers two selectable setpoints on the same sensor. The 962 can be set for high/low level alarm detection or pump control. In pump control mode, the unit will latch its relays internally so that no peripheral equipment is needed to perform automatic fill and drain functions.

The 961/962 is available with relay or mA output options, various transducer materials incl. plastics, aluminium or stainless steel housing, threaded and flanged process connection. The 961/962 is designed for use in ATEX intrinsically and explosion proof area as well as CIP/SIP clean environments. The construction of the device is conform to PED (Pressure Equipment Directive) regulations.

The 961/962 is not sensitive by changing density or other liquid variables and therefore does not require any calibration. The units can be used on almost each liquid with a max. viscosity of 10.000 cP, resisting temperatures up to +165°C and pressures from full vacuum service up to 138 bar.