ONLINE ELECTRONICS LTD
ID5000P_5001_A01
Page 8 of 18
3.3.
LISTENING MODE
While in LISTENING mode the unit continuously monitors the sound energy produced by the
pipeline as it waits for a pig passage to occur. The display shall be off and the LEDs around the
perimeter of the display will flash every five seconds. The relay and current loop outputs will
be in LISTENING state. There are two things that may cause this screen to change:
PIG PASSAGE – The unit is configured to recognize the unique sound signature produced by a
pig as it passes under the transducer. If the unit detects a pig passage then the unit will show
a PIG DETECTED message as per section 3.4 DETECTION MODE.
CONTROL BUTTON – Pressing the control button while the display is turned off will enter the
DISPLAY MENU interface which is described in section 3.7 SINGLE BUTTON MENU INTERFACE.
3.4.
DETECTION MODE
When a pig is detected the display will show a PIG DETECTED
message and the time and date of the event as shown. The
LEDs around the perimeter of the display will flash every
second and the relay and current loop will be in the
DETECTION state. The time and date of the pig passage are
stored in internal memory and can be viewed later using the
menu interface.
The length of time the unit will remain in this state for is determined by the OUTPUT DELAY
value. See section 3.7.7 SET OUTPUT for a description of this parameter and how to alter its
value. It should be configured to give the pig enough time to get out of the range of the sensor
after it has been detected to avoid re-trigger. When dealing with pig trains, the expected pig
speed and separation should be used to configure a suitable value for the OUTPUT DELAY such
that the unit will not detect the same pig twice but will enter LISTENING MODE in time to
detect the next pig.
Once the OUTPUT DELAY has expired, or the control button is pressed the unit will
automatically return to LISTENING MODE.
3.5.
RELAY OUTPUT
Refer to section 5 EXTERNAL CONNECTIONS for connection instructions.
While in LISTENING state, the Normally Closed (NC) contact of the relay will be connected to
the Common contact (COM) and the Normally Open (NO) contact will be open.
While in DETECTION state, the Normally Closed contact will be open and the Normally Open
contact will be connected to the Common contact.
Note that the relay logic may be INVERTED as per see section 3.7.7 SET OUTPUT.
