Soham Techno Solutions

STS works to facilate and promote clean energy to India future by aiding them through design, developing, innovating manufacturing Solar pumpControllers ranging from 1HP – 3HP Single phase , 1HP-50 HP Three Phase Sutaible for all applications. controllers are MPPT and VFD based which works on both Solar and Electricity, aavalable in three phase low voltage and high voltage AC submersible pump Our controllers are designed with low maintainance cost. Its soft starter feature prevents water hammering and increases life of the pump.

Applications:

• Tank filling
• Wildlife farms
• Rural water supply for villages homesteads
• Irrigation systems
• Fountains

 

Protection:
The SOLAR PUMP CONTROLLER products include diagnostic Features and protection from harmful conditions.

• Short circuit
• Under load
• Overheated controller
• Under voltage
• Dry run
• Locked pump
• Reverse polarity

Additional Information:

• Item Code: STS
• Production Capacity: 100 NOS PER WEEK
• Delivery Time: 3-4 WORKING DAYS
• Packaging Details: BOX PACKING

STS provide single phase solar pump controller 1 hp and 2hp
which can run your existing single phase pump and motor.

Additional Information:

• Item Code: STSSP
• Production Capacity: 100 NOS PER WEEK
• Delivery Time: 3-4 WORKING DAYS
• Packaging Details: BOX PACKING

Solar pump Contoller;
STS works to facilate and promote clean energy to India future by aiding them through design, developing, innovating manufacturing Solar pump Controllers ranging from 1HP – 3HP Single phase , 1HP-50 HP Three Phase Sutaible for all applications. controllers are MPPT and VFD based which works on both Solar and Electricity, available in three phase low voltage and high voltage AC submersible pump Our controllers are designed with low maintainance cost. Its soft starter feature prevents water hammering and increases life of the pump.

Applications:

• Tank filling
• Wildlife farms
• Rural water supply for villages homesteads
• Irrigation systems
• Fountains

 

Protection:
The SOLAR PUMP CONTROLLER products include diagnostic Features and protection from harmful conditions.

• Short circuit
• Under load
• Overheated controller
• Under voltage
• Dry run
• Locked pump
• Reverse polarity

Additional Information:

• Item Code: STS1160TP
• Production Capacity: 100 NOS PER WEEK
• Delivery Time: 2-3 DAYS
• Packaging Details: BOX PACKING

3 Phase Solar Pump STS works to facilate and promote clean energy to India future by aiding them through design, developing, innovating manufacturing Solar pump with Controllers ranging from 1HP – 2HP Single phase , 1HP-50 HP Three Phase Sutaible for Agriculture Pumps. in Which controllers are MPPT and VFD based which works on both Solar and Electricity, aavalable in three phase low voltage and high voltage AC submersible pump Our controllers are designed with low maintainance cost. Its soft starter feature prevents water hammering and increases life of the pump.

STS provide solar submersible pumps, openwell and monoblock pumps with low voltage SS, semi SS and CI series pumps which can gives a better prerformance even in a low radiation.

Additional Information:

• Item Code: STS2SPC
• Production Capacity: 100 NOS PER WEEK
• Delivery Time: 3-4 WORKING DAYS
• Packaging Details: BOX PACKING

Solar pump Contoller;
STS works to facilate and promote clean energy to India future by aiding them through design, developing, innovating manufacturing Solar pump Controllers ranging from 1HP – 3HP Single phase , 1HP-50 HP Three Phase Sutaible for all applications. controllers are MPPT and VFD based which works on both Solar and Electricity, available in three phase low voltage and high voltage AC submersible pump Our controllers are designed with low maintainance cost. Its soft starter feature prevents water hammering and increases life of the pump.

Applications:

• Tank filling
• Wildlife farms
• Rural water supply for villages homesteads
• Irrigation systems
• Fountains

 

Protection:
The SOLAR PUMP CONTROLLER products include diagnostic Features and protection from harmful conditions.

• Short circuit
• Under load
• Overheated controller
• Under voltage
• Dry run
• Locked pump
• Reverse polarity

STS works to facilate and promote clean energy to India future by aiding them through design, developing, innovating manufacturing Solar pumpControllers ranging from 1HP – 3HP Single phase , 1HP-50 HP Three Phase Sutaible for all applications. controllers are MPPT and VFD based which works on both Solar and Electricity, aavalable in three phase low voltage and high voltage AC submersible pump Our controllers are designed with low maintainance cost. Its soft starter feature prevents water hammering and increases life of the pump.

Applications:

• Tank filling
• Wildlife farms
• Rural water supply for villages homesteads
• Irrigation systems
• Fountains

 

Protection:
The SOLAR PUMP CONTROLLER products include diagnostic Features and protection from harmful conditions.

• Short circuit
• Under load
• Overheated controller
• Under voltage
• Dry run
• Locked pump
• Reverse polarity

STS works to facilate and promote clean energy to India future by aiding them through design, developing, innovating manufacturing Solar pump Controllers ranging from 1HP – 3HP Single phase , 1HP-50 HP Three Phase Sutaible for all applications. controllers are MPPT and VFD based which works on both Solar and Electricity, aavalable in three phase low voltage and high voltage AC submersible pump Our controllers are designed with low maintainance cost. Its soft starter feature prevents water hammering and increases life of the pump.

Applications:

• Tank filling
• Wildlife farms
• Rural water supply for villages homesteads
• Irrigation systems
• Fountains

 

Protection:
The Solar Pump Controller products include diagnostic Features and protection from harmful conditions.

• Short circuit
• Under load
• Overheated controller
• Under voltage
• Dry run
• Locked pump
• Reverse polarity

Additional Information:

• Item Code: STS1110VTP
• Production Capacity: 100 Nos Per Week
• Delivery Time: 3-4 Working Days
• Packaging Details: Box Packing

STS works to facilate and promote clean energy to India future by aiding them through design, developing, innovating manufacturing Solar pumpControllers ranging from 1HP – 3HP Single phase , 1HP-50 HP Three Phase Sutaible for all applications. controllers are MPPT and VFD based which works on both Solar and Electricity, aavalable in three phase low voltage and high voltage AC submersible pump Our controllers are designed with low maintainance cost. Its soft starter feature prevents water hammering and increases life of the pump.

Applications:

• Tank filling
• Wildlife farms
• Rural water supply for villages homesteads
• Irrigation systems
• Fountains

 

Protection:
The SOLAR PUMP CONTROLLER products include diagnostic Features and protection from harmful conditions.

• Short circuit
• Under load
• Overheated controller
• Under voltage
• Dry run
• Locked pump
• Reverse polarity

Additional Information:

• Item Code: STS1110TP
• Production Capacity: 100 NOS PER WEEK
• Delivery Time: 2-3 WORKING DAYS
• Packaging Details: BOX PACKING

STS works to facilate and promote clean energy to India future by aiding them through design, developing, innovating manufacturing Solar pumpControllers ranging from 1HP – 3HP Single phase , 1HP-50 HP Three Phase Sutaible for all applications. controllers are MPPT and VFD based which works on both Solar and Electricity, aavalable in three phase low voltage and high voltage AC submersible pump Our controllers are designed with low maintainance cost. Its soft starter feature prevents water hammering and increases life of the pump.

Applications:

• Tank filling
• Wildlife farms
• Rural water supply for villages homesteads
• Irrigation systems
• Fountains

 

Protection:
The Solar Pump Controller products include diagnostic Features and protection from harmful conditions.

• Short circuit
• Under load
• Overheated controller
• Under voltage
• Dry run
• Locked pump
• Reverse polarity

Additional Information:

• Item Code: STS3230415VTP
• Production Capacity: 100 NOS PER WEEK
• Delivery Time: 2-3 WORKING DAYS
• Packaging Details: BOX PACKING

STS 25HP THREE PHASE Solar Pump Controller;
STS works to facilate and promote clean energy to India future by aiding them through design, developing, innovating manufacturing Solar pump Controllers ranging from 1HP – 3HP Single phase , 1HP-50 HP Three Phase Suitable for all applications. controllers are MPPT and VFD based which works on both Solar and Electricity, available in three phase low voltage and high voltage AC submersible pump Our controllers are designed with low maintenance cost. Its soft starter feature prevents water hammering and increases life of the pump.

Applications:

• Tank filling
• Wildlife farms
• Rural water supply for villages homesteads
• Irrigation systems
• Fountains

 

Protection:
The SOLAR PUMP CONTROLLER products include diagnostic Features and protection from harmful conditions.

• Short circuit
• Under load
• Overheated controller
• Under voltage
• Dry run
• Locked pump
• Reverse polarity

Additional Information:

• Item Code: STS25415TP
• Production Capacity: 100 NOS PER MONTH
• Delivery Time: 3-4 WORKING DAYS
• Packaging Details: BOX PACKING

STS works to facilate and promote clean energy to India future by aiding them through design, developing, innovating manufacturing Solar pump with Controllers ranging from 1HP – 2HP Single phase , 1HP-50 HP Three Phase Sutaible for Agriculture Pumps. in Which controllers are MPPT and VFD based which works on both Solar and Electricity, aavalable in three phase low voltage and high voltage AC submersible pump Our controllers are designed with low maintainance cost. Its soft starter feature prevents water hammering and increases life of the pump.

STS provide solar submersible pumps, openwell and monoblock pumps with low voltage SS, semi SS and CI series pumps which can gives a better prerformance even in a low radiation.

Additional Information:

• Item Code: STSPC
• Production Capacity: 100 NOS PER MONTH
• Delivery Time: 3-4 WORKING DAYS

STS works to facilate and promote clean energy to India future by aiding them through design, developing, innovating manufacturing Solar pumpControllers ranging from 1HP – 3HP Single phase , 1HP-50 HP Three Phase Sutaible for all applications. controllers are MPPT and VFD based which works on both Solar and Electricity, aavalable in three phase low voltage and high voltage AC submersible pump Our controllers are designed with low maintainance cost. Its soft starter feature prevents water hammering and increases life of the pump.

Applications:

• Tank filling
• Wildlife farms
• Rural water supply for villages homesteads
• Irrigation systems
• Fountains

Protection:

The Solar Pump Controller products include diagnostic Features and protection from harmful conditions.

• Short circuit
• Under load
• Overheated controller
• Under voltage
• Dry run
• Locked pump
• Reverse polarity

Additional Information:

• Item Code: STS2160VTP
• Production Capacity: 100 Nos Per Week
• Delivery Time: 3-4 Working Days
• Packaging Details: Box Packing

STS works to facilate and promote clean energy to India future by aiding them through design, developing, innovating manufacturing Solar pumpControllers ranging from 1HP – 3HP Single phase , 1HP-50 HP Three Phase Sutaible for all applications. controllers are MPPT and VFD based which works on both Solar and Electricity, aavalable in three phase low voltage and high voltage AC submersible pump Our controllers are designed with low maintainance cost. Its soft starter feature prevents water hammering and increases life of the pump.

Applications:

• Tank filling
• Wildlife farms
• Rural water supply for villages homesteads
• Irrigation systems
• Fountains

 

Protection:
The SOLAR PUMP CONTROLLER products include diagnostic Features and protection from harmful conditions.

• Short circuit
• Under load
• Overheated controller
• Under voltage
• Dry run
• Locked pump
• Reverse polarity

Additional Information:

• Item Code: STSTP
• Production Capacity: 100 NOS PER WEEK
• Delivery Time: 3-4 WORKING DAYS

STS works to facilate and promote clean energy to India future by aiding them through design, developing, innovating manufacturing Solar pump with Controllers ranging from 1HP – 2HP Single phase , 1HP-50 HP Three Phase Sutaible for Agriculture Pumps. in Which controllers are MPPT and VFD based which works on both Solar and Electricity, aavalable in three phase low voltage and high voltage AC submersible pump Our controllers are designed with low maintainance cost. Its soft starter feature prevents water hammering and increases life of the pump.

STS provide solar submersible pumps, openwell and monoblock pumps with low voltage SS, semi SS and CI series pumps which can gives a better prerformance even in a low radiation.

Additional Information:

• Item Code: STSSPC5
• Production Capacity: 100 NOS PER MONTH
• Delivery Time: 3-4 WORKING DAYS
• Packaging Details: BOX PACKING

STSSPC10 Solar Pump Controller STS works to facilate and promote clean energy to India future by aiding them through design, developing, innovating manufacturing Solar pump with Controllers ranging from 1HP – 2HP Single phase , 1HP-50 HP Three Phase Sutaible for Agriculture Pumps. in Which controllers are MPPT and VFD based which works on both Solar and Electricity, aavalable in three phase low voltage and high voltage AC submersible pump Our controllers are designed with low maintainance cost. Its soft starter feature prevents water hammering and increases life of the pump.

STS provide solar submersible pumps, openwell and monoblock pumps with low voltage SS, semi SS and CI series pumps which can gives a better prerformance even in a low radiation.

Additional Information:

• Item Code: STSSPC10
• Production Capacity: 100 NOS PER MONTH
• Delivery Time: 5-6 WORKING DAYS
• Packaging Details: BOX PACKING

3 Phase Solar Pump With Contoller STS works to facilate and promote clean energy to India future by aiding them through design, developing, innovating manufacturing Solar pump with Controllers ranging from 1HP – 2HP Single phase , 1HP-50 HP Three Phase Sutaible for Agriculture Pumps. in Which controllers are MPPT and VFD based which works on both Solar and Electricity, aavalable in three phase low voltage and high voltage AC submersible pump Our controllers are designed with low maintainance cost. Its soft starter feature prevents water hammering and increases life of the pump.

STS provide solar submersible pumps, openwell and monoblock pumps with low voltage SS, semi SS and CI series pumps which can gives a better prerformance even in a low radiation.

Additional Information:

• Item Code: STSSPC5HP
• Production Capacity: 100 NOS PER WEEK
• Delivery Time: 3-4 WORKING DAYS
• Packaging Details: BOX PACKING

Solar Pump Combo STS works to facilate and promote clean energy to India future by aiding them through design, developing, innovating manufacturing Solar pump with Controllers ranging from 1HP – 2HP Single phase , 1HP-50 HP Three Phase Sutaible for Agriculture Pumps. in Which controllers are MPPT and VFD based which works on both Solar and Electricity, aavalable in three phase low voltage and high voltage AC submersible pump Our controllers are designed with low maintainance cost. Its soft starter feature prevents water hammering and increases life of the pump.

STS provide solar submersible pumps, openwell and monoblock pumps with low voltage SS, semi SS and CI series pumps which can gives a better prerformance even in a low radiation.

Additional Information:

• Item Code: STSSPC
• Production Capacity: 100 NOS PER WEEK
• Delivery Time: 5-6 WORKING DAYS
• Packaging Details: BOX PACKING

Solar pump Contoller;
STS works to facilate and promote clean energy to India future by aiding them through design, developing, innovating manufacturing Solar pump Controllers ranging from 1HP – 3HP Single phase , 1HP-50 HP Three Phase Sutaible for all applications. controllers are MPPT and VFD based which works on both Solar and Electricity, available in three phase low voltage and high voltage AC submersible pump Our controllers are designed with low maintainance cost. Its soft starter feature prevents water hammering and increases life of the pump.

Applications:

• Tank filling
• Wildlife farms
• Rural water supply for villages homesteads
• Irrigation systems
• Fountains

 

Protection:
The SOLAR PUMP CONTROLLER products include diagnostic Features and protection from harmful conditions.

• Short circuit
• Under load
• Overheated controller
• Under voltage
• Dry run
• Locked pump
• Reverse polarity

Additional Information:

• Item Code: STS20415VTP
• Production Capacity: 50 NOS PER MONTH
• Delivery Time: 5-6 WORKING DAYS
• Packaging Details: BOX PACKING

Solar Pump STS works to facilate and promote clean energy to India future by aiding them through design, developing, innovating manufacturing Solar pump with Controllers ranging from 1HP – 2HP Single phase , 1HP-50 HP Three Phase Sutaible for Agriculture Pumps. in Which controllers are MPPT and VFD based which works on both Solar and Electricity, aavalable in three phase low voltage and high voltage AC submersible pump Our controllers are designed with low maintainance cost. Its soft starter feature prevents water hammering and increases life of the pump.

STS provide solar submersible pumps, openwell and monoblock pumps with low voltage SS, semi SS and CI series pumps which can gives a better prerformance even in a low radiation.

Additional Information:

• Item Code: STSSPC1
• Production Capacity: 100 NOS PER WEEK
• Delivery Time: 3-4 WORKING DAYS
• Packaging Details: BOX PACKING

STS works to facilate and promote clean energy to India future by aiding them through design, developing, innovating manufacturing Solar pump Controllers ranging from 1HP – 3HP Single phase , 1HP-50 HP Three Phase Sutaible for all applications. controllers are MPPT and VFD based which works on both Solar and Electricity, available in three phase low voltage and high voltage AC submersible pump Our controllers are designed with low maintenance cost. Its soft starter feature prevents water hammering and increases life of the pump.

Applications:

• Tank filling
• Wildlife farms
• Rural water supply for villages homesteads
• Irrigation systems
• Fountains

 

Protection:
The SOLAR PUMP CONTROLLER products include diagnostic Features and protection from harmful conditions.

• Short circuit
• Under load
• Overheated controller
• Under voltage
• Dry run
• Locked pump
• Reverse polarity

Additional Information:

• Item Code: STS15415TP
• Production Capacity: 100 NOS PER MONTH
• Delivery Time: 5-6 WORKING DAYS
• Packaging Details: BOX PACKING

30HP THREE PHASE 415V Solar Pump Controller
STS works to facilate and promote clean energy to India future by aiding them through design, developing, innovating manufacturing Solar pump Controllers ranging from 1HP – 3HP Single phase , 1HP-50 HP Three Phase Suitable for all applications. controllers are MPPT and VFD based which works on both Solar and Electricity, available in three phase low voltage and high voltage AC submersible pump Our controllers are designed with low maintenance cost. Its soft starter feature prevents water hammering and increases life of the pump.

Applications:

• Tank filling
• Wildlife farms
• Rural water supply for villages homesteads
• Irrigation systems
• Fountains

 

Protection:
The SOLAR PUMP CONTROLLER products include diagnostic Features and protection from harmful conditions.

• Short circuit
• Under load
• Overheated controller
• Under voltage
• Dry run
• Locked pump
• Reverse polarity

Additional Information:

• Item Code: STS30415VTP
• Production Capacity: 50 NOS PER MONTH
• Delivery Time: 5-6 WORKING DAYS
• Packaging Details: BOX PACKING

Solar Pump STS works to facilate and promote clean energy to India future by aiding them through design, developing, innovating manufacturing Solar pump with Controllers ranging from 1HP – 2HP Single phase , 1HP-50 HP Three Phase Sutaible for Agriculture Pumps. in Which controllers are MPPT and VFD based which works on both Solar and Electricity, aavalable in three phase low voltage and high voltage AC submersible pump Our controllers are designed with low maintainance cost. Its soft starter feature prevents water hammering and increases life of the pump.

STS provide solar submersible pumps, openwell and monoblock pumps with low voltage SS, semi SS and CI series pumps which can gives a better prerformance even in a low radiation.

Additional Information:

• Item Code: STSSPC1HP
• Production Capacity: 100 NOS PER WEEK
• Delivery Time: 3-4 WORKING DAYS
• Packaging Details: BOX PACKING

STS SUPPLIES submersible water pump is in high demand due to its innovative mechanical design and impeccable quality. It is available in all size range starts from 100 mm. Our submersible motor pumps are manufactured from the superlative quality raw material using premier manufacturing technology. They encompass both optimum performance and excellent quality. Our submersible water pump is anti-corrosion nature and provides high wear resistance it reduces the running costs due to its high pumping efficiency and longevity. It can work continuously for a longer period of time without any trouble. They are highly reliable and provide best results even under harsh conditions.

STS works to facilate and promote clean energy to India future by aiding them through design, developing, innovating manufacturing Solar pump Controllers ranging from 1HP – 3HP Single phase , 1HP-50 HP Three Phase Sutaible for all applications. controllers are MPPT and VFD based which works on both Solar and Electricity, aavalable in three phase low voltage and high voltage AC submersible pump Our controllers are designed with low maintainance cost. Its soft starter feature prevents water hammering and increases life of the pump.

Applications:

• Tank filling
• Wildlife farms
• Rural water supply for villages homesteads
• Irrigation systems
• Fountains

 

Protection:
The Solar Pump Controller products include diagnostic Features and protection from harmful conditions.

• Short circuit
• Under load
• Overheated controller
• Under voltage
• Dry run
• Locked pump
• Reverse polarity

Additional Information:

• Item Code: STS10415TP
• Production Capacity: 100 Nos Per Month
• Delivery Time: 3-4 Working Days
• Packaging Details: Box Packing

STS SOLAR PUMP CONTROLLER
FOR SINGLE PHASE AND THREE PHASE PUMPS
STS works to facilate and promote clean energy to India future by aiding them through design, developing, innovating manufacturing Solar pumpControllers ranging from 1HP – 3HP Single phase , 1HP-50 HP Three Phase Sutaible for all applications. controllers are MPPT and VFD based which works on both Solar and Electricity, aavalable in three phase low voltage and high voltage AC submersible pump Our controllers are designed with low maintainance cost. Its soft starter feature prevents water hammering and increases life of the pump.

Applications:

• Tank filling
• Wildlife farms
• Rural water supply for villages homesteads
• Irrigation systems
• Fountains

 

Protection:
The SOLAR PUMP CONTROLLER products include diagnostic Features and protection from harmful conditions.

• Short circuit
• Under load
• Overheated controller
• Under voltage
• Dry run
• Locked pump
• Reverse polarity

Solar pump Contoller;
STS works to facilate and promote clean energy to India future by aiding them through design, developing, innovating manufacturing Solar pump Controllers ranging from 1HP – 3HP Single phase , 1HP-50 HP Three Phase Sutaible for all applications. controllers are MPPT and VFD based which works on both Solar and Electricity, available in three phase low voltage and high voltage AC submersible pump Our controllers are designed with low maintainance cost. Its soft starter feature prevents water hammering and increases life of the pump.

Applications:

• Tank filling
• Wildlife farms
• Rural water supply for villages homesteads
• Irrigation systems
• Fountains

 

Protection:
The SOLAR PUMP CONTROLLER products include diagnostic Features and protection from harmful conditions.

• Short circuit
• Under load
• Overheated controller
• Under voltage
• Dry run
• Locked pump
• Reverse polarity

STS works to facilate and promote clean energy to India future by aiding them through design, developing, innovating manufacturing Solar pumpControllers ranging from 1HP – 3HP Single phase , 1HP-50 HP Three Phase Sutaible for all applications. controllers are MPPT and VFD based which works on both Solar and Electricity, aavalable in three phase low voltage and high voltage AC submersible pump Our controllers are designed with low maintainance cost. Its soft starter feature prevents water hammering and increases life of the pump.

Applications:

• Tank filling
• Wildlife farms
• Rural water supply for villages homesteads
• Irrigation systems
• Fountains

 

Protection:
The SOLAR PUMP CONTROLLER products include diagnostic Features and protection from harmful conditions.

• Short circuit
• Under load
• Overheated controller
• Under voltage
• Dry run
• Locked pump
• Reverse polarity

STS works to facilate and promote clean energy to India future by aiding them through design, developing, innovating manufacturing Solar pumpControllers ranging from 1HP – 3HP Single phase , 1HP-50 HP Three Phase Sutaible for all applications. controllers are MPPT and VFD based which works on both Solar and Electricity, aavalable in three phase low voltage and high voltage AC submersible pump Our controllers are designed with low maintainance cost. Its soft starter feature prevents water hammering and increases life of the pump.

Applications:

• Tank filling
• Wildlife farms
• Rural water supply for villages homesteads
• Irrigation systems
• Fountains

 

Protection:
The SOLAR PUMP CONTROLLER products include diagnostic Features and protection from harmful conditions.

• Short circuit
• Under load
• Overheated controller
• Under voltage
• Dry run
• Locked pump
• Reverse polarity

Additional Information:

• Item Code: STSCONTROLLER
• Production Capacity: 100 NOS PER WEEK
• Delivery Time: 3-4 WORKING DAYS
• Packaging Details: BOX PACKING

STS works to facilate and promote clean energy to India future by aiding them through design, developing, innovating manufacturing Solar pumpControllers ranging from 1HP – 3HP Single phase , 1HP-50 HP Three Phase Sutaible for all applications. controllers are MPPT and VFD based which works on both Solar and Electricity, aavalable in three phase low voltage and high voltage AC submersible pump Our controllers are designed with low maintainance cost. Its soft starter feature prevents water hammering and increases life of the pump.

Applications:

• Tank filling
• Wildlife farms
• Rural water supply for villages homesteads
• Irrigation systems
• Fountains

 

Protection:
The SOLAR PUMP CONTROLLER products include diagnostic Features and protection from harmful conditions.

• Short circuit
• Under load
• Overheated controller
• Under voltage
• Dry run
• Locked pump
• Reverse polarity