NR, NR4

Summary

Product Identification

The Calpeda NR and NR4 series are close-coupled, single-impeller, centrifugal in-line pumps. They feature an electric motor with an extended shaft directly connected to the pump. The pump casing has suction and delivery connections of the same diameter and on the same axis.

Models:

• NR: 2-pole induction motor (n ≈ 2900 rpm)
• NR4: 4-pole induction motor (n ≈ 1450 rpm)
• NR EI, NR4 EI: Versions with integrated frequency converter (I-MAT) for variable-speed operation.

Connections:

• Flanges PN 10, EN 1092-2 for NR, NR4 sizes 32, 40, 50, 65.
• Screwed flanges PN 16, EN 1092-1 for NR4 sizes 100, 125.
• Flanges for welding PN 10, EN 1092-1 are also available.
• Counterflanges are available on request.

Applications

These pumps are designed for clean, non-abrasive, and non-aggressive liquids, with a maximum solids content of up to 0.2%.

Typical applications include:

• Heating, conditioning, cooling, and circulation plants.
• Civil and industrial applications.
• Situations requiring low noise operation (NR4 series, n ≈ 1450 rpm).

Operating Limits

• Liquid temperature: From -10 °C to +90 °C
• Ambient temperature: Up to 40 °C
• Total suction lift: Up to 7 m
• Maximum permissible working pressure: Up to 10 bar
• Duty: Continuous duty

Electrical

Motor Type: 50 Hz induction motors.

NR Series (2-pole, n ≈ 2900 rpm):

• NR (three-phase):
  • 230/400 V ± 10% up to 3 kW
  • 400/690 V ± 10% from 4 to 18,5 kW
• NRM (single-phase): 230 V ± 10%

NR4 Series (4-pole, n ≈ 1450 rpm):

• NR4 (three-phase):
  • 230/400 V ± 10% up to 3 kW
  • 400/690 V ± 10% for 4 kW
• NRM4 (single-phase): 230 V ± 10%

General Electrical Specifications:

• Insulation class: F
• Protection: IP 54
• Frequency converter suitability:
  • From 0,75 kW for NR4
  • From 1,1 kW for NR
• Efficiency: Classification scheme IE3 for three-phase motors from 0,75 kW.
• Compliance: Constructed in accordance with EN 60034-1, EN 60034-30-1, EN 60335-1, EN 60335-2-41.

NR EI, NR4 EI (Pumps with Frequency Converter):

• Rated motor power output: From 0,25 kW to 18,5 kW.
• Control range (2-pole): 1750 to 2900 rpm.
• Control range (4-pole): 870 to 1450 rpm.
• Protections:
  • Dry running
  • Operations with closed valve ports
  • System leakages
  • Overcurrent in the motor
  • Overvoltage and undervoltage of the power supply
  • Current unbalances between phases
• Operating modes:
  • Constant pressure mode (with pressure transducer)
  • Proportional pressure mode (with pressure transducer)
  • Constant flow mode (with flow meter)
  • Fixed speed mode (with setting of the speed preferential rotation)
  • Constant temperature mode (with temperature transducer)

Mechanical / Hydraulic

Construction:

• Close-coupled, single-impeller, centrifugal design.
• In-line pump casing with same-diameter suction and delivery connections on the same axis.

Materials:

• Pump casing: Cast iron GJL 200 EN 1561
• Lantern bracket: Cast iron GJL 200 EN 1561
• Impeller:
  • Cast iron GJL 200 EN 1561
  • Brass P-Cu Zn Pb 2 EN 1982 for NR-NR4 32, 40, 50 models
• Shaft:
  • Chrome-nickel steel AISI 303 for pumps up to 1.1 kW
  • Chrome steel AISI 430 for pumps from 1.5 to 18,5 kW
• Mechanical seal: Carbon - Ceramic - NBR
• Counterflanges: Steel Fe 42 UNI 7070

Performance Data

Detailed performance curves and tables for various models (NR, NR4, NR EI, NR4 EI) showing head (H) vs. flow rate (Q), power input (P1), rated motor power output (P2), and efficiency (η) are available in the official PDF.

Dimensions and Weights

Detailed dimensions (fM, h1, h2, AD, l1, l2, x, Øb) and weights (kg) for all NR, NR4, NR EI, and NR4 EI models are provided in tabulated form in the official PDF. Flange dimensions (DN, DE, W, DG, DK, N° Ø Holes) are also specified.

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Disclaimer: This summary is based on extracted text and may not include all figures, footnotes, or the latest revisions from the original OEM PDF. Contractual data must always match the specific OEM PDF revision used for the project.

Official datasheet (PDF)

Lenntech datasheet mirror