Variable Speed Systems - Loma IQ2 Service Manual

Do not forget to re-select Photo eye if it has been temporarily disabled during
the ferrite calibration procedure. If the wand has been removed and cannot be
found then the following options are available:
The compensation value for Product F can be re-entered manually by accessing
the Compensation menu position in the "Manual Setup" menu for Product F.
Reference your User Manual for details on the Compensation menu position.
The compensation value for Product F, if not recorded by you, can be obtained
from your local Group Service Centre. When requesting information always
quote the Serial Number of your equipment. The number is located on the
Serial Number label inside the Control Unit
section of this manual.
Now go back to the User Options menu and disable the access to Product F
(Access ferrite). The control unit is now fully commissioned for your application.

VARIABLE SPEED SYSTEMS

On systems employing variable speed conveyors, special hardware is required
to drive the CTB (Conveyor Time Base) input on the micro control card.
Conveyor systems supplied by LOMA will already have this hardware fitted and
commissioned, but on head only sales the following information should be
observed when using variable speed.
Overview
In order for the reject timing to work correctly, it must be supplied with
information about how far the contaminant has travelled between the head and
point of reject. This is achieved via a shaft encoder which supplies pulses to the
CTB input of the micro control board - refer to the optional Connection Ladder
diagram located in the Wiring/Connection Diagrams section of this manual.
The delay information, which is entered in the Product Setup menu, then counts
the CTB pulses out to time the contaminated product to the reject point. For this
reason the delay is measured in distance, and should be set at the fastest
conveyor speed in order for the reject device to actuate in time. The dwell, on
the other hand, should be set at the slowest belt speed to guarantee accurate
rejection at all speeds. The dwell can be in units of time or distances depending
upon the type of reject device.
Module 7026
Configuration and Set up Information
in the Service Return
on page 2
5-11