abem Terraloc Pro 2, Руководство пользователя

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ABEM Terraloc Pro 2
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Triggering Methods
To make a recording with the Terraloc Pro 2 seismic system, an initiating trigger signal
is required. The trigger pulse defines the start of the data recording and is the reference
for all timing.
Make/Break Switch Input
The system will trigger if the wires of the trigger cable are shorted together (make
switch), or if the shorted wires are opened (break switch).
When you use explosives, one trigger method is to put a few turns of wire around the
charge. The wire is cut by the explosion and triggers the seismograph (break switch).
You can also twist a pair of insulated wires together and insert the twisted part into the
dynamite. The explosion will compress the wires and crush/melt the insulation causing
the leads of the wires to short together. This will trigger the seismograph (make switch).
Besides, this make switch triggering method can be applied when you use falling weight
or hammer as energy source. However, you must use a metallic shock plate and the
falling weight or the hammerhead must be made out of metal. Connect one lead of the
trigger wire to the shock plate and the other lead to the falling weight or hammerhead.
When the hammer hits the shock plate, the trigger circuit is shorted and the instrument
triggers.
Using the Trigger Coil
If you want to trigger Terraloc Pro 2 with the ignition current going out to the charge,
you can use the Trigger Coil (current detector unit) included in the Terraloc Pro 2
accessories. To use this you merely feed one of the two shot wires through the hole in
the trigger coil. The trigger coil is either connected directly to the trigger input or to the
extension connectors on the trigger cable reel. Then set the Terraloc Pro 2 in the
"Analog" trigger input mode with the sensitivity control set at about 50 %. When the
charge is fired, the ignition current will trigger Terraloc Pro 2 instantly. The current
pickup trigger method is very convenient since you only need to bring the shot cable to
the shot hole.
Note! You have to use (seismic) blasting caps with no built-
in delay to be able to use this method. If you use
ordinary blasting caps the ignition delay will be
included in your record. There are seismic blasting
caps of the safety type available. Their delay is only
some 50 µs if fired with a high power-blasting
machine.
Radio Triggering
In case you need to trigger the Terraloc Pro 2 in places where you cannot use a trigger
cable, you can use a simple radio equipment to transmit the trigger pulse.