UHF PD Sensor for Transformers  USENST - Rugged Monitoring
                     USENS-T: UHF PARTIAL DISTC3H0A1RGE 
SENSOR
- Highly Sensitive, Wide band, UHF PD Sensors for Transformers
- Rugged design, 100% Leak proof
- Easy to Install, Integrated Transient (Over-voltage) Protection
- High Dielectric, shielded to avoid electromagnetic interface
- Suitable for extreme environment, Outdoor Substation
- Customized according to Transformer tank size & inspection 
covers
Rugged design, highly sensitive and accurate Partial Discharge sensor for 
detecting and  monitoring   partial  discharge  activity  inside  Oil  Filled  and  
Dry  Type Transformers/Reactors.
Product Summary
CIGRE, TB662 and TB 343 recommends to install UHF PD sensors on transformer tank wall for Partial Discharge (PD) 
activity detection and real time monitoring. Rugged Monitoring has developed the most advanced UHF PD sensor for 
Transformers, capable of detecting smallest PD activities inside transformer tank.
USENS-T is an Ultra High Frequency (UHF) antenna that is capable of measuring Electromagnetic PD signals from the 
inside of transformer. The sensors are IP68 rated, easy to install on transformer tank and suitable for all types of 
Transformers. The sensors can easily be bolted on transformer tank (or inspection cover) directly touching the oil or 
with dielectric window in-between the sensor and oil. Higher sensitivity (up to -90dBm) over wide range of 
frequencies (200
- 3000 MHz) helps in reducing the cost of PD monitoring, hence higher ROI (Return on Investment).
Rugged Monitoring USENS-T is designed to fit on the transformer tank (or inspection cover) of different types of 
transformers at all voltage levels. The sensors can also be customized according to customer technical requirements. 
Sensor's built-in overvoltage protections and N-type connection allows them to be connected with any UHF based PD 
monitoring system, regardless of manufacturers.
Applications
- Power Transformer PD Testing and Monitoring - Continuous Online Partial Discharge Monitoring
- Reactor PD Testing and Monitoring - Periodic Partial Discharge Testing and Measurements
- Distribution Transformer PD Testing and Monitoring - High Voltage Testing during Commissioning
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Benefits
- Higher sensitivity (-90dBm); detect even - Integrated overvoltage protection, for the safety 
smallest PD activity of PDM electronics
- Wider frequency response, compatible - Rugged design, IP68 Protection, Longer life
with all PDM systems - 100% leak proof sensor
- High Dielectric Strength, Safest installation - Customizable according to the 
and operation customer requirements
- Shielded Sensor, Lower Signal-to-Noise 
Ratio
TECHNICAL SPECIFICATIONS
UHF Frequency Response 200 - 3000 MHz
Sensitivity up to -90 dBm
Average Effective Height 
over 500MHz –  1500MhHz 25mm+
Min. Effective Height over 500Mhz –  1500Mhz 16mm+
Withstand Voltage up to 1500 kV
Output N-Type connector; Customized option available
Connector Circuit Impedance 50 Ω
Oil Pressure up to 10bar
Vacuum Tightness < 0.10 mbar, Leakage rate < 0.0001 mbar/sec
Vibration Testing Suitable for HV - GIS and Transformer applications
Ingress Protection (IP) IP-68
Ambient (Operating Temperature) -60 ⁰C to +150 ⁰C
Storage Temperature -60 ⁰C to +150 ⁰C
Operating Humidity 95% humidity at 50 ⁰C
Dimensions Customized as per Transformer Flange Design
Weight app. 1.5 KG; Customized as per customer requirements / Transformer Design
Install Position Transformer Tank, Inspection Cover, Transformer Dielectric Window
Signal Cable Very low attenuation UHF (Coax) cable
ORDERING CODE Sensor depth from Type of Sensor the Flange (in cm) 
(i.e. D, B, S, P hh = 01 to 99 cm
etc.)
Sensor Model #
Y = 0 to 9
U S E N S -  T  x - B d d -  H h h -  Y Sensor Connector
Z 1 : N Type 
UHF Sensor Hole diameter on (Standard)
Transformer Transformer Tank (in 2 : TNC
cm) dd = 01 to 99 cm 3 : BNC
Rugged Monitoring Services About Rugged Monitoring
Rugged Monitoring provides customization of sensors, Industry leading team of fiber optic experts with 100+ years 
monitors & software. In addition we offer on-site of combined experience committed to delivering 
commissioning services, maintenance contracts and customizable solutions for challenging applications. We 
technical support to all customers worldwide. offer a range of reliable,  high  performance,  
customizable  sensors  and monitoring solutions that are 
immune to external influence.
2018 Rugged Monitoring Company. All rights reserved. Information subject to change without notice. All trademarks are properties of their respective 
companies, as noted herein.
+1-418-767-0111 [email protected] www.ruggedmonitoring.com
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