CROPSCAN OC16

Onion RH Controller

Developed from the successful OC8 Onion RH Controller the Cropscan OC16 gives the operator many more advanced control features and "on board datalogging" capability.

This controller provides Stage 1 and Stage 2 Onion Curing control plus Re-Heat option.  On most Onion Store installations the OC16 dovetails with the Cropscan 16mc3 temperature controller to provide Stage 3 control.

Up to 16 Crop RH sensors can be monitored with one Duct RH sensor and optional Ambient RH sensor.  A duct temperature sensor gives both readout and High and/or Low Temp Alarm function.  All Crop RH sensors are scanned and the operator can allocate controlling sensors.  Large LED Digital Readouts of Crop RH, Duct RH and Duct Temp are constantly displayed.

A High Visibility 4 Line Blue/White LCD display gives easy access to all settable parameters and in depth readouts, plus a 1 hour frequency, 7 day LOOK BACK record of RH values and Fan Run Times.

Red LED lamps indicate all key Output activity at a glance.

Stage 1 Control
The store-motorised louvres are modulated to maintain a Duct RH within + or - 2% of the Set Level. In this mode the Fan Output is On continuously.  Duct temp alarm is available as an option.

Stage 2 Control
The Main Fans are controlled On-Off based on the Crop RH High and Low settings. Any number of Crop RH sensors can be programmed On-Off Duty as required. The store motorised louvres are modulated to maintain a Duct RH within + or - 2% of Set Level.  Duct temp alarm is available as an option.

Stage 3 Selection
Stage 3 (Temperature Control) is not available on this controller. Normally a separate control device such as a Cropscan 16mc3 would be utilised. The Onion Controller has a Stage 3 selection, which stops all RH control outputs but still allows readouts of current RH values to be displayed.

Heating Control
The Main Fans are controlled On-Off based on the Crop RH High and Low settings.  Any combination of Crop RH sensors can be programmed On-Off Duty as required.

The store motorised louvres are maintained fully open when fans are On.  Duct Temp alarm is available as an option.

Interface to Motor Control/Louvre Panel
Provision will need to be made on the main panel to allow a Temperature or RH control changeover, when transferring control from the Onion Control to the Cropscan 16mc3.

Heaters
The heaters used in Onion Drying are not controlled directly by the Onion Controller. They will usually be a self-contained device with a temperature setting made separately. They would normally be interlocked and switch on if selected in Stages 1 or 2 when the fans are started.

RH Sensors
Crop sensors would normally connect via a 4 or 8 way remote junction box and link back with a multicore cable. Sensors intended for use in a bulk onion stack or for box stores are mounted within a 110mm diameter plastic pipe to afford protection and maintain a free airflow across the RH sensor.