Transmitter Patterns - CDI CD42 Instruction Manual

Transmitter Patterns

If you are using multiple transmitters in a pig train, it is usually useful to be able to distinguish these
pigs from one another. The newer CDI transmitters (CD42-T0, CD42-T1A, CD42-T1, CD42-T2) have
the capability to transmit both the standard pulsing pattern or a pattern that is selectable by the operator.
The easiest way to use this feature is to simply flip a switch located inside the transmitter‟s body. If
you have a programmable transmitter, remove its end cap and look down into the cavity. You should
see a set of two tiny switches located in the bottom of the unit where the battery carousel normally
makes contact (if you don‟t see switches then the transmitter is not programmable). These switches are
shown in Figure 76, Figure 76 and Figure 78 and have the ability to put the transmitter into several
different modes of operation. The modes are:
Figure 76
Pulsing Pattern
Figure 76
Figure 77
Skip One Mode
Figure 78
Constant-On Mode
Any of CDI‟s transmitters have the ability to be programmed with a pulse pattern that is completely
configurable, and in addition have the ability to have a delay-on time programmed that can be as long
as several months. These transmitters accomplish this by incorporating a very tiny computer that drives
the electronics. This transmitter then has the ability to have software uploaded to it that modifies its
behavior. Contact CDI at support@pigging.com, or on our web site at www.pigging.com, or by calling
us at +1(918)258-6068 to discuss programming custom waveforms and delay-on times.
CD42 Pipeline Pig Location & Tracking System
1. Standard CD42-T1 pulsing pattern (default) (Figure 76)
The standard mode where the transmitter emits a continuous
string of pulses. In this mode the transmitter will emit a pulse
every 1.5 seconds.
"Skip one" mode (Figure 77)
2.
Instead of transmitting a constant string of pulses the
transmitter emits two pulses and then "skips one" before
emitting two more pulses. This allows you to distinguish one
transmitter from another in a train that is emitting a standard
continuous string, but it can also be used to conserve battery
power if your job is long.
3. Constant-on mode (Figure 78)
This mode causes the transmitter to emit a continuous
magnetic field without pulsing. This mode is particularly
useful when the transmitter is being used for benchmarking
through the pipeline and you are concerned that a pulsing
transmitter could be missed.
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