Description
The GeoPak HPTX-70 is a High-Powered Transmitter (Tx) system designed for both electromagnetic and galvanic mode geophysical surveys. The purpose of the HPTX-70 is to provide a better quality primary signal and consequently allow for high resolution, large scale or deep search geophysical surveys. Core to its design is provision for safe operation while maximizing efficiency of deployment.
Three HPTX-70's have now been commissioned. Gap Geophysics operates these systems from our bases in Kalgoorlie, WA and Mt Isa, Qld.
Overview
The HPTX-70 is capable of output power of up to 70 kW and can be used for both time and frequency domain surveys. It is designed to produce a high amplitude, high quality, precisely timed signal.
-
Powered by a four cylinder turbo charged Deutz diesel engine running at 1800 rpm
-
Four voltage settings up to 1200 V
-
Capable of output current up to 350 Amps into low resistance loops.
-
Can be controlled by Gap, Zonge and EMIT Tx controllers or internal controller
-
Constant voltage and controlled current modes
-
Can be operated remotely using a PDA and wireless communications
-
Control software allows monitoring and display of all Tx functions.
-
Trailer-mounted designed for applications where vegetation and topography permit vehicle access.
Performance
The HPTX-70 transmitter has four selectable voltage ranges:
|
Voltage
|
Min Volts
|
Max Volts
|
Max Amps
|
|
Range 1
|
100
|
200
|
350
|
|
Range 2
|
200
|
350
|
200
|
|
Range 3
|
350
|
700
|
100
|
|
Range 4
|
700
|
1200
|
60
|
The performance of the HPTX-70 can be modelled for various loop configurations using GapTxCalc.
EM Applications
The HPTX-70 is capable of maximum current output of 350A. The high current output means that the HPTX-70 is an ideal transmitter for electromagnetic surveys (EM) of all survey configurations including:
-
Fixed loop (FLEM)
-
Moving loop (MLEM)
-
Down hole (DHEM) surveys.
Galvanic Applications
The HPTX-70 is capable of maximum output voltages up to 1200V. The HPTX-70 transmitter can be used for galvanic mode surveys such as:
-
Induced Polarisation (IP)
-
Magnetometric Resistivity (MMR)
-
Sub-Audio Magnetics (SAM)
Safety Considerations
-
Fully enclosed all-in-one configuration.
-
Electrical components are protected from the environment.
-
Electrical and mechanical components are inaccessible during operation.
-
Safety interlocks on all doors.
-
No manual lifting during setup.
-
Reduced trip hazards – all of the cabling is internal apart from the output loop and earth wires.
-
Operating voltage range is generally within the insulation rating of commonly used wire.
-
Circuit breakers – installed on each electrical phase from the alternator
-
Remote operation capability(cable or wireless)
-
Safety beacons
-
Safety guards on moving parts and dummy loads
-
Emergency shutdown
-
Automatic shutdown on error conditions
-
Open circuit protection
-
Internal bunding for the fuel tank
-
Aluminium construction - lightweight
-
Electric brakes with breakaway safety switch.
HPTX-70 (GAP702) operating on a mining site in Western Australia
