Vega Borehole Motors
A Vega submersible borehole motor sits below the pump end in the borehole and turns it, cooled by the water flowing past on its way into the pump. Vega makes oil-filled motors in 3-inch, 4-inch and 6-inch sizes and water-filled, rewindable motors in 6-inch and 8-inch, on 220V single-phase, 220V three-phase, 380V and 525V. This guide shows how to match a motor to your pump end, the full specifications, and current prices.
Motor Sizes
3", 4", 6" and 8"
NEMA couplings
Power Range
0.18 – 75 kW
220V, 380V and 525V
Protection
IP68
Fully submersible
Cooling
Oil or water filled
Water-filled are rewindable
Pressure Rating
20 – 35 bar
By size and type
4" Motors
From R1 434
Incl. VAT
Match the motor to the pump end
A borehole motor is chosen by four things, in this order. Get any one wrong and the pump either will not fit, will not start, or will burn out.
- Diameter – the same size as the pump end: a 4" pump end needs a 4" motor. The 10SP pump ends state on the listing whether they take a 6" or 8" motor.
- Power – exactly the kW shown on the pump end listing. A smaller motor overloads; a bigger one wastes money and may not suit the control box.
- Voltage – what is available on site: 220V single-phase, 380V or 525V three-phase. 220V three-phase motors are for solar inverters and VSDs.
- Oil or water filled – see below. In 4" and smaller, Vega motors are oil filled; from 6" you can choose.
A single-phase motor needs its control box. The start and run capacitors live in the control box on the surface, not in the motor. Always buy the Vega control box or 20Y controller rated for the same kW.
Oil-filled or water-filled?
| Oil-filled | Water-filled | |
|---|---|---|
| Vega sizes | 3", 4" and 6" | 6" and 8" |
| Pressure rating | 20 bar (4"), 25 bar (6") | 35 bar |
| Repair | Sealed unit, normally replaced | Stator replaceable and rewindable |
| Filled with | Oil, sealed at the factory | Clean water, checked before installation |
| Best for | Domestic and small farm boreholes | Deep, high-power and continuous-duty installations |
Water-filled motors are the usual choice for large and deep installations, because they can be rebuilt rather than replaced, and there is no oil to leak into the borehole. Oil-filled motors are compact and simple for domestic sizes.
Vega motor ranges
| Range | Supply | Power | Rating | Price range |
|---|---|---|---|---|
| 3" oil filled | 220–240V 1-phase | 0.18 – 1.5 kW | – | R1 271 – R2 529 |
| 4" oil filled | 220–240V 1-phase | 0.37 – 2.2 kW | 20 bar | R1 449 – R3 080 |
| 4" oil filled | 220V 3-phase (solar and VSD) | 0.37 – 5 kW | 20 bar | R1 434 – R6 659 |
| 4" oil filled | 380–415V 3-phase | 0.37 – 7.5 kW | 20 bar | R1 560 – R6 651 |
| 4" oil filled | 525V 3-phase | 2.2 – 7.5 kW | 20 bar | R8 416 – R17 025 |
| 6" oil filled | 380–415V 3-phase | 5.5 – 30 kW | 25 bar | R7 790 – R20 714 |
| 6" oil filled | 525V 3-phase | 5.5 – 30 kW | 25 bar | R17 968 – R52 726 |
| 6" water filled | 380–415V 3-phase | 5.5 – 37.5 kW | 35 bar | R7 790 – R28 081 |
| 6" water filled | 525V 3-phase | 22 – 37.5 kW | 35 bar | R38 614 – R48 214 |
| 8" water filled | 380–415V 3-phase | 45 – 75 kW | 35 bar | R49 606 – R60 037 |
| 8" water filled | 525V 3-phase | 45 – 75 kW | 35 bar | R55 829 – R70 066 |
4-inch motor specifications
Vega 4" oil-filled motors have a stainless steel casing, a maximum diameter of 95 mm, IP68 protection, class B insulation and a sand-proof cover with pressure-balance membrane and mechanical seal. Speed is 2850 rpm and the flange and coupling follow the NEMA standard.
220–240V single-phase
| Motor | kW | HP | Run capacitor | Running amps | Length | Weight |
|---|---|---|---|---|---|---|
| 4SDm-0.37 | 0.37 | 0.5 | 20 µF | 3.7 A | 314 mm | 6.7 kg |
| 4SDm-0.55 | 0.55 | 0.75 | 25 µF | 4.7 A | 329 mm | 7.3 kg |
| 4SDm-0.75 | 0.75 | 1.0 | 35 µF | 6.2 A | 344 mm | 8.0 kg |
| 4SDm-1.1 | 1.1 | 1.5 | 45 µF | 8.0 A | 399 mm | 10.6 kg |
| 4SDm-1.5 | 1.5 | 2.0 | 55 µF | 10.5 A | 424 mm | 11.7 kg |
| 4SDm-2.2 | 2.2 | 3.0 | 60 µF | 15 A | 502 mm | 15.7 kg |
380–415V three-phase
| Motor | kW | HP | Running amps | Length | Weight |
|---|---|---|---|---|---|
| 4SD-0.37 | 0.37 | 0.5 | 1.5 A | 314 mm | 6.7 kg |
| 4SD-0.55 | 0.55 | 0.75 | 1.8 A | 329 mm | 7.3 kg |
| 4SD-0.75 | 0.75 | 1.0 | 2.5 A | 344 mm | 8 kg |
| 4SD-1.1 | 1.1 | 1.5 | 3.2 A | 379 mm | 9.8 kg |
| 4SD-1.5 | 1.5 | 2.0 | 4.3 A | 424 mm | 11.7 kg |
| 4SD-2.2 | 2.2 | 3.0 | 6.0 A | 514 mm | 15.7 kg |
| 4SD-3 | 3.0 | 4.0 | 8.0 A | 594 mm | 19.8 kg |
| 4SD-4 | 4.0 | 5.5 | 10.0 A | 698 mm | 23.7 kg |
| 4SD-5.5 | 5.5 | 7.5 | 13.0 A | 788 mm | 28 kg |
| 4SD-7.5 | 7.5 | 10.0 | 17.0 A | 908 mm | 34 kg |
6-inch motor specifications
Oil filled, 380–415V
IP68, class F insulation, 2500 N thrust load, maximum submerged depth 250 m, water pH 6.5 – 8.0, minimum cooling flow along the motor 8 cm/s, 10 – 30 starts per hour depending on size.
| Motor | kW | HP | Current | Length | Weight |
|---|---|---|---|---|---|
| HTY6-5.5 | 5.5 | 7.5 | 12.3 A | 580 mm | 42 kg |
| HTY6-7.5 | 7.5 | 10 | 16.5 A | 620 mm | 46 kg |
| HTY6-9.2 | 9.2 | 12.3 | 20.2 A | 655 mm | 50 kg |
| HTY6-11 | 11 | 15 | 23.6 A | 685 mm | 53 kg |
| HTY6-13 | 13 | 17.5 | 27.6 A | 715 mm | 56 kg |
| HTY6-15 | 15 | 20 | 31.8 A | 755 mm | 59 kg |
| HTY6-18.5 | 18.5 | 25 | 38.2 A | 820 mm | 66 kg |
| HTY6-22 | 22 | 30 | 45.2 A | 880 mm | 73 kg |
| HTY6-26 | 26 | 35 | 53.5 A | 930 mm | 80 kg |
| HTY6-30 | 30 | 40 | 61.6 A | 980 mm | 86 kg |
Water filled, 380V and 525V
Polywrapped winding, IP68, stainless steel shell and shaft, replaceable stator, maximum water temperature 35 °C, maximum immersion 350 m, cooling flow 0.2 m/s, allowable voltage variation +6% / −10%.
| kW | HP | Length (SS) | Length (CI) | Weight motor only | Weight packed |
|---|---|---|---|---|---|
| 5.5 | 7.5 | 747 mm | 727 mm | 46 – 49 kg | 51 – 54 kg |
| 7.5 | 10 | 777 mm | 757 mm | 50 – 54 kg | 54 – 58 kg |
| 9.3 | 12.5 | 803 mm | 787 mm | 53 – 59 kg | 57 – 63 kg |
| 11 | 15 | 847 mm | 827 mm | 61 – 63 kg | 65 – 67 kg |
| 13 | 17.5 | 897 mm | 877 mm | 64 – 67 kg | 68 – 71 kg |
| 15 | 20 | 937 mm | 917 mm | 70 – 71 kg | 75 kg |
| 18.5 | 25 | 992 mm | 972 mm | 76 – 80 kg | 80 – 84 kg |
| 22 | 30 | 1067 mm | 1047 mm | 90 kg | 94 kg |
| 26 | 35 | 1127 mm | 1107 mm | 94 – 97 kg | 98 – 101 kg |
| 30 | 40 | 1247 mm | 1227 mm | 100 – 102 kg | 105 – 108 kg |
| 37.5 | 50 | 1347 mm | 1347 mm | 126 – 128 kg | 131 – 134 kg |
SS = stainless steel construction, CI = cast iron construction. Weight ranges cover both.
8-inch water-filled motors
For 8VP and large 10SP pump ends. Coupling to NEMA standard, IP68, maximum 20 starts per hour, maximum immersion 350 m, supplied with 3 m of 4-core cable, maximum water temperature 35 °C.
| kW | HP | Net weight | Gross weight | 380V price | 525V price |
|---|---|---|---|---|---|
| 45 | 60 | 165 kg | 183 kg | R49 606 | R55 829 |
| 55 | 75 | 205 kg | 223 kg | R58 381 | R65 678 |
| 75 | 100 | 220 kg | 245 kg | R60 037 | R70 066 |
The 55 kW motor is listed on our store as 56 kW, as it appears on the price list.
Keeping a borehole motor alive
- Cooling flow. The motor is cooled by water moving past it into the pump. In a wide casing, or with the pump below the screens or in open water, fit a flow-inducer sleeve.
- Water temperature. Full rating applies in water up to 35 °C.
- Sand. 4" motors are rated for up to 40 g/m³ of sand. More than that wears seals and bearings.
- Voltage at the motor. Size the cable for the full length. Low voltage on start-up is the most common cause of burnt windings.
- Starts per hour. Stay within the datasheet limit. A pressure tank or a VSD controller reduces starts.
- Dry-run protection. A Vega 20Y, Y1 or 30Y controller switches off before the motor runs without water.
- Water-filled motors must be filled with clean water and checked for air before they go down the hole.
Price guide
| Motor range | Models | Price range | |
|---|---|---|---|
| 3" oil filled 220V | 7 | R1 271 – R2 529 | Shop |
| 4" oil filled 220V single-phase | 6 | R1 449 – R3 080 | Shop |
| 4" oil filled 220V three-phase | 8 | R1 434 – R6 659 | Shop |
| 4" oil filled 380V | 10 | R1 560 – R6 651 | Shop |
| 4" oil filled 525V | 5 | R8 416 – R17 025 | Shop |
| 6" oil filled 380V | 10 | R7 790 – R20 714 | Shop |
| 6" oil filled 525V | 10 | R17 968 – R52 726 | Shop |
| 6" water filled 380V | 11 | R7 790 – R28 081 | Shop |
| 6" water filled 525V | 3 | R38 614 – R48 214 | Shop |
| 8" water filled 380V | 3 | R49 606 – R60 037 | Shop |
| 8" water filled 525V | 3 | R55 829 – R70 066 | Shop |
Prices include VAT and are correct at the time of writing. The product page always shows the current price.
Frequently asked questions
Which Vega motor do I need for my pump end?
The same diameter and exactly the same kW as shown on the pump end listing, in the voltage you have on site. A 4-inch pump end rated 1.1 kW needs a 4-inch 1.1 kW motor.
What is the difference between oil-filled and water-filled motors?
Oil-filled motors are sealed units and are normally replaced when they fail. Water-filled motors are filled with clean water and can be rewound, so they are preferred for large and deep installations.
Do single-phase borehole motors need a control box?
Yes. The start and run capacitors are in the surface control box. Use a Vega control box or 20Y controller rated for the same kW.
What is a 220V three-phase borehole motor for?
It is designed to run from a solar pump inverter or a variable speed drive that produces 220V three-phase from a single-phase or DC supply. It is not for direct connection to a 380V supply.
How deep can a Vega borehole motor be installed?
Vega 4-inch oil-filled motors are rated 20 bar, 6-inch oil-filled motors to 250 m submerged depth and the water-filled 6-inch and 8-inch motors to 350 m immersion. Check the pump head as well.
How hot can the water be?
Vega borehole motors are rated for water up to 35 °C at full load.
Can a Vega motor drive another brand of pump end?
Yes, if the pump end has a NEMA coupling of the same size and needs the same kW. Vega motors use NEMA-standard flanges and couplings.
Why did my borehole motor burn out?
The usual causes are low voltage at the motor from undersized cable, dry running when the water level dropped, too many starts per hour, sand, or a control box of the wrong kW. A dry-run controller and correct cable prevent most failures.
Need help matching a motor?
Send us the pump end model, borehole depth, cable length and the power on site. We will confirm the motor, control box and cable size.
Related guides
- Vega Borehole Pumps — pump ends and kits
- Vega Pump Controllers — control boxes and protection
- Vega Variable Speed Drives — constant pressure and soft start
- Vega Solar Pumps — DC motors and inverters
- Vega Pumps — the full Vega range
- Vega Submersible Electric Borehole Motors — shop the category