Wintriss SmartPAC 2, Руководство пользователя

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SmartPAC 2 with WPC 2000 Integration User Manual 1128600
Program Mode 5-17
Most contact sensors can be used as either normally open or normally closed, depending on
how they are connected. Some electronic sensors can be switched to work either as normally
open or normally closed. Most sensors are used as normally open because no current is
flowing in the normal state.
Ready Signal
For many sensors, like those that monitor part ejection, blow-off, or feed advance, the event
being monitored must occur during a specific portion of the stroke. If the event doesn’t occur
during this period, the die may be damaged. The portion of the stroke during which a sensor
must actuate is called the Ready signal. You set a Ready signal only for green sensors, which
monitor events that must occur on every stroke.
The term “Ready signal” derives from older die protection systems on which a mechanical
cam switch on the press sent a signal to the die protection unit during the range of angles
within which the sensor must actuate.
The Ready signal is set by keying in the beginning (called “ready on”) and ending (called
“ready off”) angles of the range of angles during which the sensor must actuate. If the sensor
does not actuate (i.e., closure to ground does not occur) during this window, SmartPAC 2
sends a stop command to the press. The type of stop (i.e., top stop, emergency stop, or smart
stop) is programmable. See
Setting Sensor Stop Type
, page 5-25.
Impedance
Impedance is a measure of the resistance to the flow of electric current. Some die protection
controls have inputs for electromechanical sensors that provide different impedances. As a
rule of thumb, use a high-impedance input if the part is dirty or covered with a non-conductive
lubricant. Use a low-impedance input if the part is covered with a water-based or conductive
lubricant.
DiProPAC boards shipped since August, 2007 are compatible with all impedance levels.
However, DiPro Sensor Interface (DSI) 2 cannot be used with low-impedance sensors. If you
have a low-impedance application (e.g., a wire probe application in which a part/strip covered
with a water-based, conductive lubricant completes the circuit), the sensor must be wired
directly to the DiProPAC board.
Sensor Types
Sensors used with die protection systems are classified as red, yellow, or green. For
SmartPAC 2 with DiProPAC, there are four types of green sensors—green, green quick
check, green constant, and green special—all of which require an event to occur on every
stroke or at least once during a set number of strokes.
When you make settings for a tool, you select the sensor type for each sensor connected to
SmartPAC 2. You can program any combination of reds, yellows, or greens. Instructions for
programming sensor types is provided starting on page 5-24.