IOM CRUZcontrol® Generation2 for NBC
P/N: 1118211
Revision Date: 05/31/2019
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Example 2: Progressive Logic Accumulation Release Control
CRUZcontrol Logic Assemblies set to Progressive Logic mode provide for high throughput rates and
efficient release, compared to Basic Logic mode. In simple terms, Basic Logic tries to create zone
length gaps in the flow of product, where as Progressive Logic allows product to flow without creating
gaps.
The product throughput rate for Progressive Logic, measured in case-feet per minute, can equal the
conveyor speed. This can create problems. If, for example, an NBC-C conveyor running at 180 feet per
minute is feeding product to an induction belt conveyor running at 100 feet per minute, the belt
conveyor will be overrun, meaning that excessive line pressure will build up at the discharge end of the
NBC-C.
There are several possible solutions to handle this situation:
1. The speed of the accumulation conveyor could be set at less than the speed of the next
conveyor down-stream. In the example mentioned, if the NBC-C were running at 100 feet per
minute, there wouldn’t be an issue. This is not often possible. If the accumulation conveyor
needed to receive product at a higher input rate, the speed would have to be higher. If densely
packed accumulation were desired, that would also require the speed to be above 100 feet per
minute.
2. The release of product from the accumulation conveyor could be logically controlled so as to
limit the release rate. If the NBC-C running at 180 feet per minute were to be given a
Singulation Release signal for 3.3 seconds, and then kept off for 2.7 seconds, with that
sequence repeating, the theoretical release rate should be close to 100 product-feet per minute
(180 fpm x 3.3 sec. / (3.3 sec. + 2.7 sec.)). The actual release rate could be more, with product
coast and shorter than zone length product lengths allowing more product than expected to
progress past the release point. Assuming that the release signal is PLC controlled, an
advantage to this approach is that the release sequence timing could be easily altered to
increase or decrease the release rate.
The CRUZcontrol Logic Assembly at the final discharge zone could be set to Basic Logic mode, with all
other upstream Logic Assemblies set to Progressive Logic mode. This would reduce the NBC-C
release rate while still retaining the infeed and throughput rate benefits of Progressive Logic mode. The
release rate would be a function of the speed of the accumulation conveyor, the speed of the receiving
conveyor, and also the size and weight characteristics of the conveyed product. If the NBC-C running
at 180 feet per minute had a Logic Assembly set to Basic Logic mode at only the discharge end, the
release rate would be closer to the 100 product feet per minute capacity of the downstream induction
belt conveyor.
