BAE-SPS3 JOLA strip electrode

Description

The BAE-SPS3 JOLA strip electrode signals via an electrode relay the presence of liquid medium due to, for example, a burst pipe. Floor electrodes are designed for use in dry rooms.

BAE-SPS3 with integrated galvanic isolation:

• prevents interconnection of electrode circuits
• prevents the formation of earth loops when more than one detector is connected to a common power supply circuit.

BAE-SPS conductive strip electrodes. use only in normally dry environments. They can be used on floors, ceilings, along pipes or in two-pipe systems. They should be located at the lowest point of the potential hazard area to be monitored.

BAE-SPS. The strip electrodes are equipped with two separate electrodes in the form of two stainless steel ropes: 1 control electrode and 1 ground electrode. As soon as a trace of conductive liquid creates a conductive path between the two stainless steel ropes, the switching state of the leak detector changes.

In contrast to the cable electrodes on the previous pages, the strip electrodes do not have two separate sensor cables. The two stainless steel ropes are integrated in a halogen-free polyester strap, ensuring that the spacing between them remains constant. This polyester tape is designed to prevent stainless steel ropes from coming into contact with each other or with an electrically conductive surface (e.g. steel tub, steel pipes, etc.), thus preventing false alarms while allowing leaking liquid to penetrate the stainless steel ropes.

To avoid false alarms, it is essential that the surroundings of the strip electrodes are completely dry under normal circumstances, as strip electrodes have the ability to bind moisture (including high levels of humidity in the air), which can lead to false alarms in environments that are not completely dry, especially with long strip electrodes.

Conductive measurement principle

The principle of conductive measurement is used to detect electrically conductive liquids. Not suitable for the detection of electrically non-conductive liquids.

Electrically conductive liquids are usually aqueous solutions of salts, acids or alkalis. In water, the molecules of these substances separate into positive and negative ions, which give the aqueous solution its electrical conductivity. The conductive leak detector detects the presence of an electrically conductive liquid and then sounds an alarm.

The measurement process uses alternating current to ensure accurate response sensitivity and to prevent galvanic processes at the electrodes. The conductive leak detector shall have an integrated electronic evaluation unit with galvanically isolated circuits. This prevents the electrode circuits from interconnecting and forming earth loops if more than one of these leakage detectors is connected.

Reliable detection of liquids with poor electrical conductivity, such as condensate or demineralised water, is ensured by the factory-set sensitivity response of the conductive leak detector.

BAE-SPS3 features

• design: leak detector with quiescent current / NC (interrupting)
• Sensor strip: 2 ropes of 316 Ti or 316 stainless steel, each 1,5 mm in diameter, woven into an approximately halogenated polyester fabric strip approximately 30 mm wide, spaced approximately 24-25 mm apart; length: 2 m, longer on request
• max. cable length: 30 m
• Electrode head: PC or PP
• electrical connection: three-wire connection via 3 x 0.75, 2 m connecting cable
• supply voltage: only for connection to extra low voltage SELV or PELV! (see datasheet)
• Energy consumption: max. 0.5 VA
• Output: estimate based on the magnitude of energy consumption
• short-circuit protection: present, Ik < 30 mA
• switching condition without supply voltage: low signal
• switching status with dry sensor cables: the output of the PNP transistor carries the directional supply voltage = high signal
• switching status with wet sensor leads: PNP transistor output does not carry a directional supply voltage = low signal
• sensor cable break monitoring: via the Z-4V7 cable break monitoring unit at the end of the sensor cables
• switchover condition with sensor cable line break: PNP transistor output does not carry the directional supply voltage = low signal
• cable break control of connecting cables: control of cable breakage due to quiescent current
• galvanic isolation: only for connection to extremely low voltage SELV or PELV! voltage resistance > 500 V between the capacitor circuit and the supply circuit
• max. no-load voltage on sensor cables: 10 Veff 60 Hz
• max. short-circuit current on sensor cables: 0.1 mA
• response sensitivity: approx. 30 kΩ or approx. 33 μS (conductivity)
• temperature range: – 20 °C to + 60 °C

For more technical information, please refer to the datasheet attached under the Documentation tab.

BAE-SPS3 use case: monitoring false floors in a server room using a cable electrode and a panel electrode in an adjacent room.

Welcome to the article ”Conductive Measurement of Liquids”