Hexamite |
HE240S Sealed Ultrasonic Sensors |
For medium range applications and harsh environment. |
HE240STX. is an Ultrasonic Ceramic Transmitter, it can produce wide beam up to 120db output SPL (sound pressure level) at 40 kHz in air Single conductor shielded cable extends from the back of this sensor, for connection to a driver circuit. HE240SRX is an Ultrasonic Ceramic Receiver, it can pick up 40Khz vibration or sound waves with, with sensitivity up to -58dB/V/microbar. Single conductor shielded cable extends from the back of this sensor. The HE240S series sensor is protected by a heavy duty chromed brass housing, with 1/8" or 3mm thick walls. The American standard NPT configuration and 3/4" pipe size, readily available mounting accessories make this sensor easy to apply and install. |
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In the following, a HE240SRX receiver is placed opposite a HE240STX transmitter at a fixed distance. The transmitter referred to as T1 is exited with various voltage levels, and the opposite receiver referred to as T2 is used to receive the signal. The graphs below plot the output from T2. |
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Microchip PIC interface suggestionsThe schematic below, shows how the PIC16C622 and the PIC16C71 can be interfaced to the HE2XX series transducers. For 40Khz transducers C1 an C2 should be about 2nF, R1 about 3Kohms and R2 about 5Kohms. R3 sets the level for the analog comparator of the PIC16C622 and should be high, say 50Kohm. If the A/D converter of the PIC16C71 is being used, R3 should be removed. |
ATMEL AVR interface suggestionsThe schematic below, shows how the AT90S2313 microcontroller can be interfaced to the HE2XX series transducers. For 40Khz transducers C1 an C2 should be about 2nF, R1 about 3Kohms and R2 about 5Kohms. R3 sets the level for the internal analog comparator of the AT90S2313 and should be high, say 50Kohm. |
INTEL 8051 interface suggestionsThe schematic on the right, shows how the INTEL 8051 microcontroller can be interfaced to the HE2XX series transducers. For 40Khz transducers C1 an C2 should be about 2nF, R1 about 3Kohms and R2 about 5Kohms. R3 sets the level for the analog comparator and should be high, say 50Kohm.
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Cable length between the HE240 series transducers and a signal conditioner, is left to the user's discretion. At 10m lengths the added environmental noise and signal reduction at 40khz is insignificant. Beam Pattern The sensor is located in the locus of the polar plot shown below facing north, maximum signal strength is along the 0 degree axis. As the observer with the measuring instruments moves east and west i.e. perpendicular to the 0 line signal strength degrades. The beam pattern character line shown below represents observation angles where signal has degraded by 6 decibels.
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Parameters | Values | Units |
Operating Frequency | 40 | kHz |
Input Voltage | 20 (max) | Volts (RMS) |
Output (SPL) | 120 | db |
Input Impedance | 300 | ohm |
Beam Spread | ±12 | degrees |
Bandwidth | 1 | kHz |
Temperature | -40 to 100 | °C |
Parameters | Values | Units |
Operating Frequency | 40 | kHz |
Receive (Sensitivity) | -58 | dB/V/Ubar |
Output Impedance | 300 | ohm |
Reception Angle | ±12 | degrees |
Bandwidth | 1 | kHz |
Temperature | -40 to 100 | °C |
Housing | Description | Units |
Material Type | Brass | |
Protection | NEMA 12 (IP68) | |
Diameter | 1.05 | In |
Diameter | 27 | mm |
Length | 1.6 | In |
Length | 41 | mm |
Leads Length (attached) | 0.3 | meters |
Panel Nut Threads | 3/4" - 20 |
NPT |