by Nicolò Passaro – Export Area Manager
In general having an inverter or frequency controlled motor allows for a great deal of advantages, some more obvious than others.
Mainly motor speed can be adjusted to match the exact RPM requirements, which translates to lower motor power consumption and lower motor stress and wear.
In a cooling tower or in cooling equipment in general, a part from the above-mentioned advantages, having a variable speed drive equipped control panel (where motor/fan speed is adjusted to a temperature set point in load following manner) allows for accurate temperature/capacity match. This has multiple advantages such as:
In most installations, if not all, load is not constant since mostly dictated by weather and process (whether in HVAC or industry). In fact, design conditions rarely occur, so having the means to reduce capacity has a great deal of importance. Imagine having to drive your car either at a standstill or flat out…not the most desired nor efficient way to use any device.
All these features combined with savings from lower consumption and lower need for spare parts make the inverter an almost essential accessory in all cooling installations.
More over in an open loop cooling tower, the inverter can avoid ice formations inside the fill pack. This is especially important in places with rigid winters where far below zero Celsius conditions regularly occur. Ice formations can be dangerous for the equipment itself as the total weight of a unit can increase tenfold and pumps would run on empty with consequences we could imagine.