The Dynergy-Hennepin power station in central Illinois, US, has switched to Rotork LA-2520 model linear modulating actuators for boiler fan inlet and outlet dampers, replacing obsolete pneumatic equipment. Faced with the choice of linear or rotary electric actuator designs, maintenance staff at the station decided that the linear LA-2520 would be easier to install and maintain. With a small footprint, it can be mounted with minimal adaptation, sometimes taking up no floor space at all. At Dynergy-Hennepin a fabricated mounting pedestal was supplied by the plant which attached to the rear clevis of the actuator, whilst the drive end clevis was supplied as a forked design to connect directly to the existing damper shaft crank arm. This has become a standard option for the Rotork LA-2000 Series. The internal servo amplifier is controlled by a 4-20mA signal and provides position feedback to the station’s control room.
