1 Overview. Pressure Measurement Single-range transmitters for general applications. 1/22 Siemens FI US Edition

Transcription

1 Siemens AG 07 SITRANS LH00 Transmitter for hydrostatic level Overview Function U const. p U I EM The pressure transmitter SITRANS LH00 is a submersible sensor for hydrostatic level measurement. The pressure transmitter measures the liquid levels in tanks, containers, channels and dams. The SITRANS LH00 pressure transmitters are available for various measuring ranges and with explosion protection as an option. A junction box and a cable hanger are available as accessories for simple installation. Sensor Connection for auxiliary power supply Vent pipe with humidity filter Protective conductor connection/ Equipotential bonding Diaphragm Benefits Compact design Simple installation Small error in measurement (0. %) Degree of protection IP68 Application SITRANS LH00 pressure transmitters are used in the following branches, for example: Shipbuilding Water/waste water supply For use in unpressurized/open vessels and wells The pressure transmitter has a built-in ceramic sensor which is equipped with a Wheatstone resistance bridge. These pressure transmitters are equipped with an electronic circuit fitted together with the sensor in a stainless steel housing. In addition, the connecting cable contains a vent pipe which is equipped with a humidity filter to prevent the build-up of condensation. The diaphragm is protected against external influences by a protective cap. The sensor, the electronics and the connecting cable are housed in an enclosure with small dimensions. The pressure transmitter is temperature-compensated for a wide temperature range. SITRANS LH00 pressure transmitter, mode of operation and connection diagram On one side of the sensor (), the diaphragm () is exposed to the hydrostatic pressure which is proportional to the submersion depth. This pressure is compared with atmospheric pressure. Pressure compensation is carried out using the vent pipe () in the connecting cable. The vent pipe is equipped with a humidity filter which prevents the build-up of condenstation in the vent pipe. The hydrostatic pressure of the liquid column acts on the diaphragm of the sensor and transmits the pressure to the Wheatstone resistance bridge in the sensor. The output voltage of the sensor is applied to the electronic circuit where it is converted into an output current of to 0 ma. The protective conductor connection/equipotential bonding () is connected to the enclosure. Integration It is generally recommended that the connecting cable of the SITRANS LH00 transmitter is connected to the junction box, which can be ordered separately, and secured with the cable hanger, also available separately. The junction box has to be installed near the measuring point. If the medium is anything other than water, it is also necessary to check compatibility with the specified materials of the transmitter. Venting pipe To measuredvalue processing To transmitter 7MF7 Junction box 7MF7-8AA, open, schematic diagram / Siemens FI 0 07 US Edition

2 Siemens AG 07 SITRANS LH00 Transmitter for hydrostatic level Technical specifications Measuring point setup, generally with junction box 7MF7-8AA and 7MF7-8AB cable hanger Pressure transmitter SITRANS LH00 (submersible sensor) Mode of operation Measuring principle piezo-resistive Input Measured variable Hydrostatic level Max. permissible operating pressure 0... mh O ( fth O). bar (.8 psi) (corresponds to mh O ( fth O)) 0... mh O (0... fth O). bar (.8 psi) (corresponds to mh O ( fth O)) 0... mh O (0... fth O). bar (.8 psi) (corresponds to mh O ( fth O)) mh O ( fth O). bar (.8 psi) (corresponds to mh O ( fth O)) mh O ( fth O).0 bar (. psi) (corresponds to 0 mho (90 fth O)) mh O ( fth O).0 bar (7. psi) (corresponds to 0 mh O (0 fth O)) bar.bar bar.bar bar.bar bar.bar 0... bar.0bar 0... bar.0bar Output Output signal...0 ma Measuring accuracy According to IEC Error in measurement at limit setting 0.% of full-scale value (typical) including hysteresis and reproducibility 0...mH O 0. % of full-scale value (typical) ( fth O bzw bar).0% of full-scale value (maximum) For all other measuring ranges 0. % of full-scale value (typical) 0.6% of full-scale value (maximum) Influence of ambient temperature Zero and span mh O (9 fth O or 0. bar) 0. %/0 K of full-scale value... 6 mh O 0. %/0 K of full-scale value (... 8 fth O or bar) > 6mH O 0. %/0 K of full-scale value ( > 8 fth O or > 0.6 bar) Long-term stability Zero and span mh O (9 fth O or 0. bar) 0. % of full-scale value/year... 6 mh O 0.% of full-scale value/year (... 8 fth O or bar) > 6mH O 0. % of full-scale value/year ( > 8 fth O or > 0.6 bar) Rated conditions Ambient conditions Process temperature C ( F) Storage temperature C ( F) Degree of protection according to IP68 IEC 609 Siemens FI 0 07 US Edition /

3 Siemens AG 07 Pressure transmitter 0. kg ( 0. lb) Cable; maximum cable length 00 m 0.0 kg/m ( 0.0 lb/ft) (0 ft) Electrical connection Cable with conductors, vent pipe and integrated humidity filter Material Seal diaphragm Al O ceramic, 96% Enclosure Stainless steel, mat. no..0/6l Gasket FPM (standard) EPDM (optional) Connecting cable PE-HD (standard) PE-LD (in the case of versions with EPDM seal, suitable for drinking water) Auxiliary power Terminal voltage on pressure transmitter U B V DC for transmitter with 0... V DC intrinsic safety explosion protection Certificates and approvals Drinking water approval (ACS) Applied for Drinking water approval (WRAS) 0 EAC TC RU C-DE.ГБ0.В.007 OC НАНИО «ЦСВЭ» Underwriters Laboratories (UL) E The transmitter is not subject to the pressure equipment directive (PED 0/68/EU) Explosion protection Intrinsic safety "i" IECEx SEV.000 SEV ATEX 009 -Marking II G Ex ia IIC T Ga Junction box Application for connecting the transmitter cable 0. kg (0. lb) Electrical connection x -way (8 to 8 AWG) Cable entry x Pg 9 Enclosure material polycarbonate Vent pipe for atmospheric pressure Rated conditions Degree of protection according to IP6 IEC 609 Cable hanger Application Material for mounting the transmitter 0.6 kg (0. lb) Galvanized steel, polyamide SITRANS LH00 Transmitter for hydrostatic level / Siemens FI 0 07 US Edition

4 Siemens AG 07 Selection and ordering data Article No. Order code Pressure transmitter 7 M F A SITRANS LH00 (submersible sensor) For measurement of the hydrostatic level through submersion, two-wire system, 0 ma, enclosure material mat. no..0 (6L), measuring cell Al O ceramic, with permanently mounted PE cable Click on the Article No. for the online configuration in the PIA Life Cycle Portal. Cable length 0...mH O ) 0 m C 0... mh O 0 m D 0... mh O 0 m E mh O 0 m F mh O 0 m H mh O 0 m K 0...9ftH O ) ft C 0... fth O ft D 0... fth O ft E fth O ft F fth O 66 ft H fth O 98 ft K bar ) 0 m C bar 0 m D bar 0 m E bar 0 m F 0... bar 0 m H 0... bar 0 m K Special versions: s for special versions between 0... mh O and mh O or fth O and fth O or bar and 0... bar possible. Special cable lenght/special measuring range Please add -Z" to Article No. and 9 A H.. + Y 0 specify Order code and plain text. Note: Indication of measuring range Y0 is always necessary. For evaluation of the maximum possible cable length following data have to be regarded: Transmitter: C i = 0 µf, L i = 0 µh Cable: C k = 0.9 nf per meter cable L k =. µh per meter cable The maximum permitted data of the transmitter s power supply have to be considered! m (0 ft) H A m (6 ft) H B 7 m ( ft) H C 0 m ( ft) H D m (9 ft) H E 0 m (66 ft) H F m (8 ft) H G 0 m (98 ft) H H 0 m ( ft) H J 0 m (6 ft) H K 60 m (98 ft) ) H L 70 m ( ft) ) H M 80 m (6 ft) ) H N 90 m (97 ft) ) H P 00 m (0 ft) ) H Q SITRANS LH00 Transmitter for hydrostatic level Selection and ordering data Article No. Order code Pressure transmitter 7 M F A SITRANS LH00 (submersible sensor) For measurement of the hydrostatic level through submersion, two-wire system, 0 ma, enclosure material mat. no..0 (6L), measuring cell Al O ceramic, with permanently mounted PE cable Sealing material between sensor and enclosure FPM (Standard) EPDM (for drinking water applications) Explosion protection without 0 With ATEX II G Ex ia IIC T Ga and IECEx Ex ia IIC T Ga Additional versions Order code Quality Inspection Certificate (-point C characteristic curve test) according to IEC , add "-Z" to article no. and add order code. Indication of measuring range (only at Y0 special cable lengths) in "... to... mh O" or "... to... fth O" or "... to... bar" Accessories/spare parts Article No. Junction box 7MF7-8AA for connecting the transmitter cable Cable hanger for securing the pressure transmitter Protective caps as spare parts (0-pack) Humidity filters as spare parts (0-pack) ) Approvals pending. 7MF7-8AB 7MF7-8AD 7MF7-8AE Siemens FI 0 07 US Edition /

5 Siemens AG 07 SITRANS LH00 Transmitter for hydrostatic level Dimensional drawings ~6. (.8) More information Establishing the measuring range for water as process medium Ø. (0.9) 6 Cable, sheat Ø.8 (0.9) (black, PE) - (green) + (brown) 6 Protective conductor connection/equipotential bonding (white) Vent pipe with humidity filter Ø (0.0) (inner diameter) Protective cap with x Ø. (0.0) holes (black, PPE) H r SITRANS LH00 pressure transmitter, dimensions in mm (inch) 86 (.9) (.0) 6 (.) Junction box, dimensions in mm (inch) 7 (.6) 7 (0.07) 7 (0.07) Fastening hole Vent valve Cable gland Pg 9, cable diameter... 8 mm ( ) 9 (0.7) 86 (.9) 0 (.) 0 (.) Calculation of the measuring range: p = ρ x g x H with: ρ = density of medium g = local acceleration due to gravity H = maximum level Example: Medium: Water, ρ = 000 kg/m Acceleration due to gravity: 9.8 m/s Start-of-scale: 0 m Maximum level: 6.0 m Cable length: 0 m Calculation: p = 000 kg/m x 9.8 m/s x 6.0 m p = N/m p = 89 mbar Transmitter to be ordered: 7MF7-FA0 Plus, if required, junction box 7MF7-8AA and cable hanger 7MF7-8AB 90 (7.) 8 (.9) Cable hanger, dimensions in mm (inch) /6 Siemens FI 0 07 US Edition