DWP Services have been using a range of variable speed pump controller for many years. We have found many of them have some advantages and some disadvantages. Here we will discuss a few to give you some guidance on what can be used.

After some years we have narrowed down inverters keeping in mind cost and performance, here is a short guide.
Motor mounted and wall mounted inverters –

Grundfos MGE and Saver

Grundfos are the biggest pump company in the world. Their reliability cannot be beaten and the technology has clearly been heavily invested in. This ensures Grundfos stays as the household name of pumps and inverters bringing complete peace of mind. The main variable speed drives is the soon to be discontinued MGE inverter and the new Saver 1 and 2 inverter. The MGE inverter has a deep parameter list for a knowledgeable engineer to fine tune to the maximum for complete efficiency and peace of mind.  But on the other hand the MGE inverter will work with the right configuration file and basic set up. It may not be running to maximum efficiency but will deliver water where you want it year after year.

The Saver inverter is the newer edition to the Grundfos family, this has a hugely expanded menu giving the customer complete configuration. Reliability and quality has not been compromised and reliability is still at the top of its game.

Grundfos are notoriously expensive to their top end products but believe you get what you pay for, if you want a long term reliable solution this may be the manufacture for you.

Xylem Lowara Hydrovar

We are now on the 5th generation of hydrovar. The years have seen complete redesigns of the hydrovar inverter but in all truth the menu and performance values have not changed too much. If you have a hydrovar it is most lijeky its the 3rd 4th or now 5th generation. Luckily enough no matter which one of these you have you can now buy an inverter to communicate with any model through its compatability software. The hydrovar is a motor or wall mounted inverter that has a pump specific set up generally used for water boosting. The excellent mulit-pump communication RS-485 is a real game changer in the pump world due to its ability to constantly keep system pressure whilst adjusting parameters or switching between units. The Hydrovar is most definitely a highly regarded inverter in the market although fairly expensive.

Coelbo Speedomatic

DWP Services is a fan of the speedomatic water cooled inverter. These units are cost effective, user friendly and reliable. The speedomatic can supply up to a 10AMP water pump and has an integral pressure and flow sensor so no need for extra wiring. They may be made out of plastic and a little bulky but now come with a LCD backlight display and a Volt Free fault contact giving the customer the ability to install and alarm to the unit in fault conditons.

Nastec Vasco

We believe this is a strong competitor in the variable speed market. This unit is wall or motor mounted just like the hydrovar and is very cost effective. The menu system is easy to navigate whilst giving a huge amount of adjustable parameters


If you require technical advise or any more information on any of these products contact DWP Services now for expert advice.

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