Geonics - Model TEM57-MK2 - Transmitter
From Time Domain Systems
The TEM57-MK2 Transmitter is the upgraded version of the TEM57, and combined with the PROTEM receiver are the principal components of the PROTEM 57-MK2 system. The design and performance of the TEM57-MK2, with increased power of 1,500 W from an internal power supply, makes it a highly portable, powerful mid-range time domain transmitter. The internal power supply has variable voltage range from 18 to 60 V so that it can be precisely matched to the transmitter loop for optimum performance. An external battery supply increases performance to 3,800 W and 160 V.
The TEM57-MK2 is the perfect mid-range power transmitter for sounding depth, thickness and conductivity of geologic layers down to 500 metres for a wide variety of applications such as mapping of aquifers and aquitards, water quality and stratigraphy. In coastal area, the PROTEM 57-MK2 system has defined depth to saline intrusion as accurately as chemical well samples.
The PROTEM 57-MK2, with a short reference cable, portable transmitter and 3-D receiver coil, can delineate complex ore bodies within 200 m of surface. Deeper conductors can be characterized by profiling with a crystal-synchronized receiver and a large, fixed transmitter loop. Modelling provides conductivity, thickness, dip and extent of the ore body.
For measurements during the turn-off (T/O) ramp, an optional T/O controller, connected externally to the transmitter, can variably increase the turn-off time, typically within the range of 200–1000 microseconds.
- Current Waveform : Bipolar rectangular current with 50% duty cycle
- Base Frequency:
- 3, 7.5, or 30 Hz where powerline frequency is 60 Hz
- 2.5, 6.25, or 25 Hz where powerline frequency is 50 Hz
- Rates below 1 Hz available from PROTEM receiver through reference cable
- Turn-Off Time : 20 to 115 µs, depending on size, current and number of turns in transmitter loop
- Transmitter Loop
- Single turn: any dimension; minimum resistance is 0.7 ohms, up to 300 x 600 m.
- 8-turn: 5 x 5 or 10 x 10 m
- Output Current : 18 to 60 V continuous control with motor generator; up to 160 V (3,800 W) with external power supply
- Synchronization : Reference cable or, optionally, quartz crystal
- Power Supply : 1,800 W, 110/220 V, 50/60 Hz single-phase motorgenerator or, optionally, multiple 12 V batteries
- Transmitter Protection : Electronic and electromechanical protection
- Dimensions : 43 x 25 x 25 cm
- Weight : 15 kg