• ...you'll be pumped

Vasco Variable Speed Controllers See all Brands

vasco pumps

A purpose-built range of variable frequency drives, designed to control and protect pumping systems based on changing pump speed.

From water supply for domestic, irrigation, liquid transfer and industrial applications, to heating and air conditioning, commercial building services, filtering pressurewashing, the VASCO range perfectly fits any new or existing application.

  • Overview
  • Technical Details
  • The Range
  • Remote Android App

Vasco also provides motor protection and monitoring, such as:

  • Protection against overload and dry running
  • Integrated soft start & soft stop functions, extending the life of the system & reducing peak absorption
  • Indication of input current and supply voltage
  • Recording running hours and logins errors and alarms reported by the system
  • The Vasco can control a second or third pump at constant speed DOL (DOL: Direct On Line)
  • Connect to other VASCO units to get combined operation

VASCO units are extremely compact and will manage the operation of the pump to maintain a constant requirement (such as pressure, flow, temperature or other). The pumping system runs only at the speed necessary to meet user's requirements, ensuring energy savings and extending the life of the system.

The body is constructed entirely of aluminium, making VASCO, with its compact dimensions, extremely solid, lightweight and easily cooled, adding to the unit's versatility. The degree of protection, IP55, makes it possible to install VASCO virtually anywhere, including a humid and dusty environment. The liquid crystal illuminated display ensures VASCO is easy to operate and a buzzer provides an immediate indication of alarm.

Wall Kit

VASCO is cooled by an external cooling fan attached to the inverter radiator. A special metal bracket is supplied for the VASCO to be wall mounted.

Vasco Wall Kit

Motor Kit

VASCO is cooled by the motor cooling fan. Motor kits consist of 4 special clamps to fix the VASCO to the motor fan cover.

Vasco Motor Kit

Installing the Vasco is Simple, User Friendly & Consists of a Few Quick Steps

If the water demand changes frequently, it is advisable to share the load using a multiple pump group, resulting in greater reliability and efficiency.

  • Connect the VASCO to power supply
  • Connect the VASCO to pump
  • Connect the VASCO to the pressure sensor , located wherever in the piping you want to maintain the desired constant physical dimension
  • Set the VASCO to configure the pump to the system, and the required performance

1 VASCO + 1 or 2 DOL

A first way of splitting consists of installing one pump driven by the VASCO and 1 or 2 DOL pumps directly connected to the main power (Direct on Line) ; VASCO alternates the two DOL pumps (same working time) to even out pump wear.

1 VASCO + 1 or 2 DOL

1 to 8 VASCO in COMBO connection

A second way of splitting (named COMBO) consists of using several pumps in parallel (up to 8) each one driven by a VASCO unit. In this way efficiency and the reliability of the pump group is maximised. Vasco controls and protects each connected pump. Each VASCO controls and protects its pump and the operation is shared among all the connected pumps to average out pump wear; in case of failure, the remaining pumps will maintain the pumping operation.

1 to 8 VASCO in COMBO connection

1 to 8 VASCO in COMBO connection + 1 or 2 DOL

Additionally, it is possible to equip the system with pumps connected in COMBO mode plus 1 or 2 DOL pumps to satisfy additional water demand.

1 to 8 VASCO in COMBO connection + 1 or 2 DOL


When first powering the VASCO, a quick initial configuration is required for complete configuration of the drive. Additional parameters can be configured later by entering 3 different setting levels:

  • End user level. The only level which can be accessed without password. It allows the user to monitor electrical and hydraulic parameters and status of the VASCO and pump.
  • Installer level. In this level , the installer can configure the VASCO pump system to the characteristics of the hydraulic system. An entry password is required.
  • Advanced level. This level allows the electrical configuration of the VASCO to the pump.
    Another entry password is required.

Initial Configuration

Constant Pressure Control

Constant Pressure Control

VASCO controls the pump speed to maintain constant pressure at a set point independent of the water demand in the system. In a hydraulic system equipped with VASCO, the standard pressure tank is replaced by a smaller tank which functions to maintain the set pressure in the system when the pump is stopped.

In traditional systems with fixed speed pumps, a larger size of pressure tank is required due to the number of pump starts and to the maximum flow rate of the pump. In large tanks, special precaution has to be taken if the working pressure is high or if there is a possibility of extended stagnation of the water causing bacteria.

Maximum & Minimum Pressure Alarm

When the pressure rises above a certain settable pressure value, Vasco will stop the pump to prevent damage to the hydraulic components in the system. Similarly, if the pressure drops below a certain set pressure, an alarm is declared and the pump is stopped.

Pressure Graph

V/F Programmable Curve


If pump runs dry, its cos phi value drops below a settable cos phi value, and VASCO stops the pump after 2 seconds. Vasco will try to start the pump every 10, 20, 40, 80 and 160 minutes, after which it will declare an alarm and stop the pump if the condition persists.


After reaching the minimum frequency at zero flow (F min Q=0) VASCO progressively slows the pump while monitoring the signal from the pressure transducer. If the pressure is close to the set pressure, Vasco stops the pump.

Zero Water Flow

Loss Compensation


Loss compensation proportional to the water flow. If the pressure sensor is placed near the pump, pressure value on the working point is lower than set pressure due to the loss proportional to the water flow. It is possible to vary the pressure set in a linear relation with respect to the frequency to compensate pressure loss in the pipes.


If pump runs dry, its cos phi value drops below a settable cos phi value, and VASCO stops the pump after 2 seconds . Vasco will try to start the pump every 10, 20, 40, 80 and 160 minutes, after which it will declare an alarm and stop the pump if the condition persists.


This parameter prevents the pump from running lower below a certain speed, avoiding the risk of damaging the thrust bearing in submersible pumps.


To prevent motor damage, the motor can accelerate quickly to reach the minimum motor frequency, and then is allowed to follow a lower start-up ramp.

Vasco Speed Controllers


If VASCO controls a submersible pump with long cables, it is possible to decrease the carrier frequency value to ensure longer motor life.


In addition to constant pressure control, VASCO allows other control modes such as fixed frequency, constant flow, constant temperature.

Vasco Speed Controllers Kit

Vasco is in position to offer a wide range of accessories including pressure sensors, flow sensors, temperature sensors, shielded cables , input EMC/RFI filters, and output dv/dt filters to protect motor windings in presence of long cables.


General Characteristics
Power frequency: 50-60 Hz (+/- 2%)
Max. ambient temperature at nominal current: 40°C (104°F)
Max. altitude at nominal current: 1000m
Grade of protection IP55

Settable Digital Output Signals (N.O or N.C):
1. Motor run signal
2. Alarm signal
3. DOL 1 pump signal
4. DOL 2 pump signal

Analogue Input (10 OR 15 VDC):
1. 4-20 mA
2. 4-20 mA
3. 4-20 mA / 0 - 10 Vdc (settable)
4. 4-20 mA / 0 - 10 Vdc (settable)

Vasco Speed Controller Single

  • 4 Digital input, N.O. or N.C (settable), for motor run & motor stop
  • RS485 serial communication

Nastec Now App allows you to communicate with all Nastec devices with Bluetooth® SMART.


  • Monitor multiple operating parameters simultaneously on the wide, high definition, coloured screen of your smartphone or tablet.
  • Get statistics of energy consumption and check alarms history.
  • Perform reports with the possibility to insert notes, images and email them or keep them into the digital archive.
  • Make programs, save them in the archive, copy them to other devices and share them among multiple users.
  • Remotely control, via wi-fi or GSM, a Nastec device, using a smartphone nearby as a modem.
Nastec Now app home

Nastec Now App is available for smartphones and tablets with Bluetooth 4.0 and Android v.4.2 or later.

Nastec Now app monitor
Nastec Now app archive
Nastec Now app status
Nastec Now app connect

Contact Form