The Polyamp Carbon fibre electrodes sensor are very sensitive. The mechanical robustness, handling and life expectancy of sensors using Carbon Fibre Technology make it much more versatile for underwater UEP/ELFE applications compared to other electrode types. The Carbon fibre sensor is in fact very sensitive and its noise is lower than the very low noise PA3004 amplifier. In differential mode low Ohmic measurements, the characteristic of the sensor is capacitive, which means a virtual DC voltage will occur. For that reason the amplifier is equipped with a High Pass filter (HP 5 mHz) to provide a stable zero level. This HP filter also protects from amplifier saturation, due to DC noise that is the most common cause of saturation on any type of highly sensitive amplifier. Therefore this HP filter is also especially relevant for AgAgCl systems.
The PA3004 very low noise differential amplifier
The Very Low Noise differential amplifier PA3004 meets demand of small footprint for underwater platform integration with the flexibility for different type of measurements.
PA3004 is optimised for both our Carbon Fibre type of sensors as well as AgAgCl electrodes.
The very wide bandwidth meets the ELFE frequency definition of 0 to 3000 Hz.
However even at near field measurements, very seldom detects usable frequencies above 500 Hz. The emphasise for signal analyses are actually the sensitivity and noise levels at frequencies below 500 Hz.
Key Features of the amplifier
- Optimised input for Carbon fibre or AgAgCl sensors by jumper setting
- Especially usefull for integration in underwater measurement platform
- Very low noise with +80/+86 dB amplification
- Noise level 1 nV RootHz @ 1 Hz
- Linearity < 1% 1 to 5000 Hz
- Selectable 80/60dB amplification by relay (-15V)
- Insulation amplifier provides excellent axis separation and common mode noise suppression
- Up up to 4 km analogue signal transfer with an optional line driver system.
pdf EST© MK II (146 KB) Educational UEP/ELFE system