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SKU: 93209321
Grundfos NB 50-250/254 Cast Iron 30 kW End Suction Centrifugal Pump with Closed Impeller
Australia-Wide
(08) 9240 2992
Official Grundfos
Peace of Mind
Product Overview
Constructed for fixed foundation mounting in mechanical rooms, the NB 50-250/254 single-stage end-suction pump connects via DN 65 suction and DN 50 discharge ports. A 30 kW electric motor provides mechanical power for continuous water circulation across building service headers.
Fluid output parameters show a rated throughput of 1525 L/Min and a maximum head limit of 75.37 m. Electrocoating treatment on the cast iron casing limits rust in hydronic loops. The internal rotor holds a stainless steel impeller with bronze wear rings. Unit physical weight is 275 kg.
Operating on a 415 V three-phase power supply, the NB 50-250/254 electric motor yields 30 kW output power with a current draw of 56 Amps. Media temperature capabilities span from -25°C to 120°C under continuous line pressures up to 16 bar. Flanged ports feature DN 65 suction and DN 50 discharge sizing.
Winding insulation on the NB 50-250/254 motor complies with Class F standards within an IP55 dust and spray resistant motor housing equipped with PTC thermistors. Service procedures benefit from back-pull-out construction, permitting internal rotor disassembly without disconnecting main system pipework headers.
Features
- Housing, impeller and wear ring use dissimilar material pairings to prevent galling and ensure no sticking elements during extended standby periods.
- High-efficiency motor selection is configured to match the specific power supply characteristics, pumping environment and liquid properties of each installation.
- Back pull-out design allows complete rotating assembly removal including motor, coupling and impeller without disturbing pump housing or connected pipework.
- EN733 and ISO2858 dimensional compliance ensures interchangeability with other standard end-suction pumps across commercial and industrial installations.
- ATEX Zone 1, 2, 21 or 22 certification available for operation in potentially explosive atmospheres (except E-model variants).
- Integrally cast suction and discharge ports with dedicated vent and drain ports provide direct connection points without additional fittings.
- No baseplate or grouting required to maintain correct shaft alignment and vibration levels within Hydraulic Institute standards.
IMPORTANT:Bulk freight charges apply. Please contact us for a freight quote before ordering.
SPECIFICATIONS
| Max Flow | 1525 L/Min |
| Max Head | 75.37 m |
| Power | 30 kW / 415v |
| Rated Current | 56 Amps |
| Suitable For | Commercial Building Services HVAC |
| Body Material | Cast Iron |
| Liquid Temperature | '-25°C to 120°C |
| Inlet Size | 65 mm |
| Outlet Size | 50 mm |
| Warranty | 24 Months |
Warranty & Returns
All products supplied by Foundation Pumps are covered by a minimum 12-month warranty unless otherwise stated. Some brands may offer longer manufacturer warranties. Warranty covers manufacturing defects, faulty materials and workmanship under normal use.
- Products must be installed correctly and in accordance with the manufacturer’s instructions.
- Warranty does not cover incorrect installation, misuse, dry running, normal wear and tear, unauthorised repairs or damage caused by external factors.
- Proof of purchase, photos, videos and installation details may be requested when assessing a warranty claim.
- The customer is responsible for returning the product to Foundation Pumps or the nominated service centre unless otherwise agreed.
- Removal, reinstallation, labour and associated site costs are generally the customer’s responsibility unless required under Australian Consumer Law.
- Change-of-mind returns may be accepted within 30 days provided the product is unused, uninstalled and returned in its original packaging.
- Customers are responsible for return freight costs for change-of-mind returns.
- Restocking fees may apply to special-order, bulky or non-stocked products.
- Used, installed or specially ordered products may not be eligible for change-of-mind returns.
- If a product arrives damaged or faulty, please contact Foundation Pumps as soon as possible so we can assist with the appropriate repair, replacement or refund.
Your rights under Australian Consumer Law are not affected.
What electrical capacity, operating voltage configuration, and current draw are engineered into this unit?
Supplied for primary boiler skids, Grundfos NB 50-250/254 features a 30 kW motor operating on a three-phase 415 V connection at 56.0 Amps.
For hot and chilled hydronic media, what thermal boundaries apply under full working pressure?
Circulating media temperatures between -25°C to 120°C are sustained by NB 50-250/254 with a maximum operating pressure of 16 bar.
For demanding campus utility networks, what maximum dynamic head is developed by this pump?
Hydraulic pressure generation certified for NB-50-250-254 establishes an operational dynamic head of approximately 75.37 m.
Supplying primary boiler plant displacement, what maximum liquid circulation rate does this unit achieve?
Within central utility plant rooms, NB 50 250 254 maintains an operational volumetric delivery of approximately 1525 L/Min.
To resist hydrodynamic wear, what alloy selection characterizes the casing and closed runner?
To prevent physical distortion from piping loads, NB/50/250/254 pairs a foot-mounted cast iron shell with a precision-cast bronze impeller.
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