Setting Reject Parameters - Thermo Scientific APEX 100 User Manual

Setting Reject Parameters

This section assumes that the reject device you are using to remove contaminated
products from the conveyor is already connected to the detector's wiring board and
ready to go to work. If a reject device is not already connected to your detector, see the
"Mechanical Set-Up for Conveyor Applications" section on page 292.
In this manual—and in the detector's menus—the main reject device is referred to as the
"Reject 1" device. Any secondary reject device is called the "Reject 2" device. The
following sections are written on the assumption that you currently have only one reject
device attached to your detector, a Reject-1 device. (For information about keying in
parameters for a Reject-2 device, see page 141.)
Reject Totals
Measurements You Will Need Before Starting
Imagine our packets of salted butter moving along the conveyor and the search head
suddenly detects a packet containing a metallic contaminant. For now, the contaminated
packet continues its journey out of the search head and along the conveyor. Around one
meter from the detector, however, the packet passes the main reject device and is
suddenly ejected from the conveyor into the reject bin. (One down, more to go!)
However, before you can begin keying in parameters to control your reject device, you
must have the following information ready.
• The distance from the downstream edge of the search head to the center of your
reject device.
• The duration of the signal needed (expressed in seconds and hundredths of a
second) to activate your reject device.
With this information in hand, you are now ready to key in the needed values. In our
salted butter example, we are going to use the following values.
• Reject distance = 1.17 meters
• Reject-signal duration = 2.02 seconds
Thermo Scientific APEX User's Guide Page 43