BD SENSORS GmbH LMK 858 Level Measurement Probe.pdf

Nominal pressure from 0... 40 cmH2O up to 0... 100 mH2O. Output signals 2-wire: 4... 20 mA, others on request. Special characteristics: diameter 45 mm, diaphragm ceramics Al2O3 99.9 %, cable assembly and sensor head detachable, chemical resistance, housing PP-HT, integrated lightning protection and increased overvoltage protection 8 kA gas discharge tube (8/20 µsec); 4 kV surge l-l/l-e according to EN61000-4-5.

Optional versions: different kinds of cables and elastomers, cable protection (on request). Detachable Plastic Probe: accuracy according to IEC 61298-2: standard 0.35 % FSO, option 0.25 % FSO.

The separable plastic immersion probe LMK 858 was designed for level measurement in aggressive media (acids, alkalis), desalination plants and for use in more viscous media such as sludge. The immersion probe is based on an extremely robust and precise pressure sensor, the membrane of which consists of a high-purity ceramic (99.9% purity), with which even the smallest fill levels can be reliably detected.

Preferred areas of use are sewage waste water treatment, dumpsite, water recycling, aggressive media level measurement in most of acids and lyes.

Technical Data: pressure and level, input pressure range, nominal pressure gauge, level, overpressure, max. ambient pressure (housing), output signal / supply, 2-wire: 4... 20 mA / VS = 9... 32 VDC, others on request.

Performance: accuracy 1, standard: ≤ ± 0.35 % FSO, option: ≤ ± 0.25 % FSO, permissible load, influence effects, supply: 0.05 % FSO / 10 V, load: 0.05 % FSO / kΩ, long term stability, ≤ ± 0.1 % FSO / year at reference conditions, turn-on time, mean response time, measuring rate, max. response time.

Thermal effects (offset and span), tolerance band, ≤ ± 1 % FSO, in compensated range -20 … 80°C, permissible temperatures, medium / electronic / environment / storage: 0... 60 °C.

Electrical protection: short-circuit protection, permanent, reverse polarity protection, no damage, but also no function, electromagnetic compatibility, emission and immunity according to EN 61326.

Overvoltage / lightning protection: series resistance, 9.4 Ω for each positive and negative wire, max. leakage current, 8 kA (8/20 µsec), overload, 4 kV (line-line and line-earth) according to EN 61000-4-5, max. rated current, 30 mA.

Electrical connection: cable with sheath material, PVC (-5 … 70 °C) grey Ø 7.4 mm, PUR (-25 … 70 °C) black Ø 7.4 mm, FEP (-25 … 70 °C) black Ø 7.4 mm, cable capacitance, signal line/shield: 160 pF/m, cable inductance, signal line/shield: 1 µH/m, bending radius, static installation: 10-fold cable diameter, dynamic application: 20-fold cable diameter.

Materials (media wetted): housing, PP-HT, seals, FKM, EPDM, others on request, diaphragm, ceramics Al2O3 99.9 %, cable sheath, PVC, PUR, FEP, others on request.

Miscellaneous: option cable protection (on request), prepared for mounting with PP-HT pipe Ø 25 mm; available as compact product (standard: pipe with a total length up to 2 m possible), current consumption, max. 25 mA, weight, approx. 400 g (without cable), ingress protection, IP 68, CE-conformity, EMC Directive: 2014/30/EU.

Wiring diagram / pin configuration: 2-wire-system (current), electrical connection, M12x1 (4-pin) 5, cable colours (IEC 60757), supply +, 3, WH (white), supply -, 4, BN (brown), shield, 2, GNYE (green-yellow), 5 if detached, supply +, supply -, VS, p, I, A.

Dimensions (mm / in): sensor head and cable detached, 174 x 45 x 32, hook diameter, 20 mm, ordering type, ordering code, weight, terminal clamp, steel, zinc plated, Z100528, approx. 160 g, terminal clamp, stainless steel 1.4301 (304), Z100527.