Owner's manual

American Sensor Technologies • 450 Clark Dr., Mt. Olive, NJ 07828 • phone [phone] • fax [phone] • email: [e-mail]
TM
Flush Diaphragm Submersible Liquid Level Sensor
AST4520
Environmental Data
Temperature
Operating -40 to 80°C (-40 to 176°F)
Storage -40 to 100°C (-40 to 212°F)
Thermal Limits
Compensated Range 0 to 55°C (32 to 131°F)
TC Zero <±1.5% of FS
TC Span <±1.5% of FS
Other
Shock 100G, 11 msec, 1/2 sine
Vibration 10G peak, 20 to 2000 Hz.
EMI/RFI Protection: Yes
Rating: IP-68
Performance @ 25°C (77°F)
Accuracy* < ±0.25% BFSL
Stability (1 year) ±0.25% FS, typical
Over Range Protection 2X Rated Pressure
Burst Pressure 5X or 1,250 PSI (whichever is less)
Pressure Cycles > 50 Million
Applications
Lift Stations - 
Wastewater, Storm Water,
Industrial Applications
Food Tanks 
Viscous Media Tanks 
Heavy Oil 
Benefits
Engraved 316L Housing 
Protective Steel Cage Assembly 
Kynar PVDF Cable 
Compatible with Wide Variety of Chemicals 
Ruggedly Designed for Harsh Waste Water 
Environments
Suitable for Waste, Salt, Brackish, or Fresh 
Water Systems
EMI/RFI and Reverse Polarity Protection 
Lightning and Surge Protection 
Competitively Priced for OEM Applications 
ABS (American Bureau of Shipping) 
Approved
The AST4520 Flush Submersible liquid level sensor is the cost effective solution
for level monitoring of turbulent tanks with viscous media. Approved to UL/
cUL913 Class 1 Division 1 IS, Groups C and D with an approved barrier, the
product ensures a safe, reliable source for level measurement. The AST4520 is
also certied to ATEX Class I Zone 0 Exia IIB T4 Ga (Ta = -40°C to +80°C).
The AST4520 is offered with pressure ranges from 0-2.5 to 0-15 PSIG. The
AST4520 steel cage front end design allows for proper ow of liquids while
keeping the sensor at the bottom of the tank or well. With an engraved stainless
steel housing and Kynar PVDF cable, this sensor is built to handle the toughest
environments.
Electrical Data
Output 4-20mA 1-5VDC
Excitation 10-28VDC 10-28VDC
Output Impedance >10k Ohms <100 Ohms, Nominal
Current Consumption: 20mA, typical <10mA
Bandwidth (-3dB): DC to 250 Hz (-3dB): DC to 1kHz
Output Noise: - <2mV RMS
Zero Offset: <±1% of FS <±1% of FS
Span Tolerance: <±2% of FS <±1.5% of FS
Output Load: 0-800 Ohms@10-28VDC 10k Ohms, min
Reverse Polarity Protection Yes Yes
For UL certied barrier
drawing, see A01657.
For CSA certied barrier
drawing, see A08949.