Specification sheet Deltapi N Series Pneumatic Transmitters Model NDC Absolute pressure transmitter GENERAL CHARACTERISTICS The blind type absolute pressure transmitter, mod. NDC, is used to measure an absolute pressure and convert it into a proportional pneumatic signal. The instrument works on the force-balance principle and consists of two main units: the measuring unit comprises a main body which houses a bellows unit, clamped in the main body forging by means of a flange. The bellows unit incorporates an evacuated reference chamber and releves the absolute pressure applied to the positive connection port. The bellows unit can withstand the maximum overrange without damage. the transmission unit converts the differential force applied to the measuring element into a proportional output pneumatic signal. The output pressure, generated by a flapper nozzle relay, is fed to a feedback bellows with a rising pressure until the bellows force balances that of the measuring element. Span value continuously adjustable by an internal micrometric screw. Zero value adjustable by an external screw. Mounting in a vertical position on 2in diameter pipe by a special bracket. OPTIONAL EXTRA FEATURES A zero suppression device allows to set as a zero of the transmitter a measured variable value different from the absolute zero. The sum of the zero suppression value (S) plus the calibrated span cannot exceed the upper range limit (M) suitable by the bellows capsule : S + span M (see table). Air filter regulator can be directly mounted on the transmitter, with or without pressure gauge, and connected with piping and fittings either in stainless steel or copper. Special versions of air filter regulator and gauges, in stainless steel, are available on request. Oxygen measurements a special degreasing and final test operations can be required on the oxygen measuring transmitter. SPECIFICATIONS The data were obtained from laboratory tests on standard instruments with: carbon steel or AISI 316L body and flange; AISI 316L bellows unit; gasket: Viton; calibration span: 800 kPa - 8 bar SPAN LIMITS 170 and 1700 kPa 1.7 and 17 bar RANGE LIMITS (absolute) lower and upper (M) 0 and 2500 kPa 0 and 25 bar Air supply nom. 140 kPa (1.4 bar, 20 psi); min. 125 kPa (1.25 bar, 18 psi); max. 175 kPa (1.75 bar, 25 psi) Output signal 20 to 100 kPa/0.2 to 1 bar, 3 to 15 psi or 0.2 to 1 kg/cm2 Static air consumption 350 Nl/h MAXIMUM ZERO SUPPRESSION (S) OVERRANGE LIMIT 2330 kPa 23.3 bar 3.5 MPa 35 bar Measuring bellows material AISI 316L, Monel Gaskets material PTFE, Viton Cover material thermoplastic resin Maximum output flow - with rising output pressure: 30 Nl/min. - with falling output pressure: 40 Nl/min. Surface protections - carbon steel body and flange: zinc plating and chrome passivation - AISI 316L body and flange: no protection Accuracy 0.5% F.S.D. (typical) Process connections (see figure ref. D ) 1/2 in NPT-F Thermal drift (for ambient temperature variation between -20 C and + 65 C) - span 170 to 340 kPa (1.7 to 3.4 bar): 0.5%/10C - span 340 to 1700 kPa (3.4 to 17 bar): 0.25%/10C Pneumatic connections - Air supply (in figure ref. A): 1/4 in NPT-F - Output (in figure ref. B): 1/4 in NPT-F Degree of protection in accordance with IEC 529 IP55 Ambient temperature limits -40 and + 120C Body and material Carbon steel, AISI 316L, Monel Body bolts and nuts material high tensile carbon steel; AISI 316 Class A4-70 per ISO 3506; high tensile stainless steel, in compliance with NACE MR0175 Pressure gauge Brass with stainless steel case (all stainless steel on request) external diameter 51 mm; 0-200 kPa, 0-2 bar and 0-30 psi indication on 82 mm/260 scale. Air filter regulator with copper or stainless steel piping, as specified. Die cast aluminium alloy with light grey epoxy finish. Net weight (maximum) 14 kg approx Packing expanded polythene box ORDERING INFORMATION Select one character or set of characters from each category and specify complete catalog number. PRODUCT CODE abc de fg hi j k lm BASE MODEL VERSION BODY AND FLANGE MEASURING ELEMENT GASKETS OUTPUT EXTRAS Code abc BASE MODEL NDC Absolute pressure transmitter de VERSION Standard with body bolts and nuts in high tensile carbon steel Standard with body bolts and nuts in AISI 316 Standard with body bolts and nuts in high tensile stainless steel fg 01 11 21 BODY AND FLANGE (*) 01 11 13 21 Carbon steel / Carbon steel AISI 316L / AISI 316L AISI 316L / Carbon steel Monel / AISI 316L (*) Only the body is in contact with fluid MEASURING ELEMENT hi Range limits - 0 and kPa psi 2500 362 2500 362 2500 362 Note 1: Multiply by 10 the value in kPa (MPa) to obtain mbar (bar). (*) Suitable for oxygen service Bellows material AISI 316L Monel AISI 316L (*) Span limits kPa (psi) - (Note 1) 170 and 1700 (24.6 and 246) 170 and 1700 (24.6 and 246) 170 and 1700 (24.6 and 246) 01 21 41 GASKETS j Measuring element gasket Viton PTFE (*) (*) k lm Fulcrum diaphragm gasket Viton PTFE (*) 2 3 Suitable for oxygen service OUTPUT 3 to 15 psi 3 to 15 psi with zero suppression device 0.2 to 1.0 kg/cm2 0.2 to 1.0 kg/cm2 with zero suppression device 20 to 100 kPa / 0.2 to 1 bar 20 to 100 kPa / 0.2 to 1 bar with zero suppression device EXTRAS Identification tag material Stainless Steel Stainless Steel Stainless Steel Stainless Steel Stainless Steel Piping material -Stainless Steel Copper Stainless Steel Copper According to ANSI/ISA S 51.1-1979 standard terminology Air filter regulator -with with with with Compliance to NACE class II bolting, according to specification MR0175, latest revision Pressure gauge ---with with 1 3 4 6 7 9 02 10 11 13 14 MOUNTING DIMENSIONS SS/NDC Rev 7 D The Company's policy is one of continuous product improvement and the right is reserved to modify the specifications contained herein without notice. ABB Ltd. Howard Road St. Neots, Cambs. England PE19 8EU Tel. (01480) 475321 Facsimile (01480) 217948 ABB Inc. 125 East County Line Road Warminster, Pa 18974 USA Tel. (215) 674-6000 Facsimile (215) 674-7183 ABB Instrumentation spa Via Statale, 113 22016 Lenno (CO) Italia Tel. 0344 58111 Facsimile 0344 56278