July 20, 2010 — Dynapar enhanced its NorthStar HSD35 mill-duty hollow shaft encoder with a 400g shock rating, optional 100C temperature limit, and enhanced sealing. Additional mill-duty features include solder-less connectors for easy field service, stainless steel shaft hub and dual-split clamp to resist common mill chemicals, and optional dual isolated outputs for redundancy. The encoder is also RoHS and CE compliant.
Mill-Duty Focus
Pulp & paper, lumber, and steel mill environments are typically harsh and downtime is considered unacceptable. Positive-latching solder-less connectors not only ensure solid connections in high shock and vibration applications, they also allow for easy field service with minimal tools: all that’s needed are a screwdriver and wire stripper to make positive connections. The mill environment also usually consists of caustic chemicals, moisture, and debris. To combat this, the HSD35 features a powder coating over hard anodizing on the housing surface and stainless steel shaft hub and clamp. Shaft corrosion can make encoder removal difficult, and in time can lead to failure.
The stainless hub clamp not only helps resist corrosion, it has higher resistance to stripped threads to ensure a more positive and durable shaft engagement.
Core Technology
The HSD35 utilizes phased-array sensing engine, unbreakable disc, bearing structure, and sealing concepts. This encoder design has proven itself in punishing environmental testing and will be a welcome benefit in a package targeted for the mill user. In common mill applications, vector-duty motors can suffer eddy current buildup on the rotor when used with high frequency drives and grounding through the hollow-shaft encoder will shorten encoder bearing life. To combat this, the HSD35 features electrical and thermal isolation on the shaft hub using composite materials.
