Component Focus: Internal Desiccant

All of the dynamic shaft seal design efforts taken by Ultra Motion will minimize the amount of liquid ingress into the actuator enclosure, but 100% moisture exclusion is not feasible. For this reason, the A2 and AM Servo Cylinders include a custom injection molded desiccant block in close proximity to the control electronics and BLDC stator to adsorb moisture over long periods of time. The desiccant block is a molecular sieve that traps moisture molecules as they migrate through the semi-solid component.

Compared to typical silica-gel desiccants, the high-performance injection molded desiccant used in the Servo Cylinder slowly adsorbs moisture over years, does not release moisture at high temperatures, and is structurally robust. This small component would normally go unnoticed, but it plays an important role in making the Servo Cylinder extremely reliable in harsh marine environments.

Our custom engineered desiccant block is also paired with a precision humidity sensor that continuously monitors relative humidity inside of the actuator’s sealed housing. This allows users to assess the functionality of the actuator’s seals and determine if the desiccant block requires service long before an unexpected problem occurs.