CLOSED LOOP "Time Cycle™" Controls

Screen feed controls regulate the movement of the filter screen based on our proprietary algorithm that has been developed and refined over decades of use in thousands of installations.  Directed by this logic, our screen changers become a fully integrated element of the extrusion process, delivering optimum performance.

'CLOSED LOOP' "TIME CYCLE™" Controls   The CLOSED LOOP algorithm uses our proprietary  Screen Guide & Resolver Assembly™ to monitor and ensure a consistent rate of screen movement. TIME CYCLE™ based controls operate on an algorithm that generates an operating cycle by which the screen advances in time cycles at a constant rate. The rate (inches or mm per hour) of screen travel is programmable and is automatically maintained by means of a feedback loop - the Resolver Assembly™.  The controls automatically compensate for minor variations in processing conditions such as fluctuations in head pressure or water temperature to maintain a consistent rate of screen advancement. This allows for fine tuning to the specific parameters of a given application, maintaining steady head pressure and conserving screen consumption.

 Features of the Closed Loop - Time algorithm:

• Operational modes: OFF/ AUTO / TEST/ MELT
• Password protected
• Screen advancement based on constant increments according to a Time Based Logic cycle. The Closed Loop-Time algorithm is used to maintain a steady incremental rate of screen travel.
• The rate of screen movement are operator selectable and adjustable
• Screen movement is verified by the controls. Immediate indication of any malfunction in screen movement is given by means of the NO FEED alarm. The automatic cycling is stopped, and the operational mode is turned  to OFF
• Variety of heating patterns for the heater(s) can be selected to customize the controls for a variety of polymer and processing conditions
  All the heating zones are monitored by temperature controllers. Power consumption indicators are also included
• Door handle is interlocked with a disconnect switch inside the enclosure

 Alarms (visual and audible)  supplied for:

• NO FEED:  screen movement cycle is not completed
• NO COOL: accidental loss of cooling water to the line
• NO HEAT alarm stops operation of the controls and returns to OFF mode, prevents tracking issues by not allowing the screen  to advance without adequate heating conditions

 Protections supplied for:

• TEST mode has max time protection
• BOOSTER and EXILT LIP heater(s) have separate protection limits against overheating in all modes
  Incorrect settings of the timers
• MELT mode has an additional protection against overheating of BOOSTER and EXIT LIP  that allows the  cooling system to expedite the drop of temperature (mainly for low flash point polymers)
• Incorrect mode selection when properly interlocked with the extruder