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The pSonic Series is an ultrasonic, 4-20mA, LoopPower level transmitter measuring level in open or enclosed silos and tanks. The measured values are reported in an analogue 4-20mA current signal.


pSonic is a compact, intrinsically safe (##X iaT6) ultrasonic, 4-20mA loop powered meter.

The electronic assembly is totally encapsulated (IP68) in ABS housing and a virtually chemically inert TefZel™ and PCV transducer casings (nose). Two LED's are used to indicate the functional status of the meter. Real time temperature compensation is applied onto the measured signals to ensure accurate reading throughout the temperature range.

The device is set up easily by touching a magnet (provided) to the designated span and zero areas on the housing.

Its unique signal processing algorithm allows the device to operate in small diameter pipes and tanks. The device also has the unique feature to be able to track fast moving targets, 4m/min the target moving towards the meter and 8m/min the target is moving away from the meter.

Open channel flow or volume can also be measured by using a pSonic in conjunction with either a BEP Controller or mSonic meter/controller. .


The pSonic is available in five models

Dead Band (mm)
Range (m)
Frequency (kHz) Approx
3dB Beam Angle
pSonic 040
pSonic 060
pSonic 080
pSonic 100
pSonic 150


There are four methods of mounting the device:

  • Suspended from the cable.
  • Suspended from a ½"in. NPT conduit.
  • Screwed into a pipe coupling threaded 2 inch NPS.
  • Screwed into a flange with 2 inch NPS thread and then bolted to a mating flange on the vessel. The use of a rubber o-ring is recommended.

Setting-up all Models

  • Touching a magnet to the circled SPAN and ZERO areas on the housing sets the device operating distances. The device has internal non-volatile storage and even when power is removed, will always remember the last set reference levels.
  • The device is set-up for the minimum level ZERO, and the maximum level SPAN, by means of momentarily contacting the respective areas marked SPAN and ZERO on the surface of the assembly with the magnetic key supplied.


Range 250mm to 15m (model dependant)
Current Output 4-20mA span directly or inversely proportional
Accuracy Better or equal to ± 0.25% of maximum span at constant temperature
Resolution 3mm / 0.12in
Point Setting By magnetic key, non-volatile storage
Status indication Two visible LED's
Fault Current 22mA or 4mA or 3.8mA (selectable)
Loop Load Rmax=Vsupply-17kOhm / 22
Beam Angle 6° tp 9° at -3 dB boundary (model dependant)
Frequency 35kHz to 80kHz (model dependant)
Storage temp -40°C / -40 °F to 80°C /176°F
Operating temp -20°C / -4°F to 60°C / 140°F, please note that instrument has internal temperature compensation
Container pressure 200 kPa (14 psi) above atmosphere
Enclosure rating 1kg / 2.2lb including integral 23ft cable
Dimensions (Model Dependant) Width - 105mm / 4.1in
Length - 105mm / 4.1in
Overall height - 112mm / 4.3in
Housing Details UV Resistant ABS housing and Tefzel™ Nose or PVC Nose
Mounting Suspended from cable or ½ in. NPT conduit, mounted
Supply voltage 17V to 30V DC (max.)
24 V DC Typical Operating Voltage
Protection Protected against reverse polarity and voltage surges
Certifications EEX ia IIC T6 (Tamb = -20°C to 60°C)
IA No.:SABS S/S828 X
U¡=28V I¡=93 P¡=0.65W L¡=4uH C¡=100nF
IEC61326-1 / IEC801-3 / EN55011


Principle of Operation

Short controlled ultrasonic pulses emanating from the device transducer are aimed at a target surface. After filtering out any noise present, the time taken for the reflected pulses to strike the sensor surface are converted to linear measurements and cconveyed to the remote indicator / recorder as a current value.




Our aim is to provide our customers with practical, cost-saving engineered solutions and through our worldwide and local/manufacture supplier contacts and service facilities, we are able to offer complete instrumentation packages. These comprehensive packages include controllers, data loggers, control panels and turnkey projects.