Sentinel 3+ Battery Sensor Gen 3+, DIN Rail Mount Compact and versatile 3 in 1 Battery sensor for monitoring of critical battery systems, included Flooded Cell, and VLRA types. The Sentinel 3+ is a state of the art, System on Chip (SoC) digital transducer designed to monitor VRLA, gel or flooded stationary battery systems. Data is transmitted over a dedicated communication bus to proprietary and non-proprietary devices Features Din Rail Mount, Compact Design LED status indicator Temperature patch for direct battery measurement Communication interface isolation 2.16 kV Fast, simple fittings , Voltage, Temperature and True AC Impedance Measurement S-Bus Output (Interface with OEM equipment) Suitable for Transformerless UPS systems (may require Common mode Isolator) Isolated plastic case recognised according to UL94-V0 Advantages Excellent sensitivity, accuracy, and repeatability High current stimulation for secure impedance measurement Improved immunity to Common Mode transients in newer UPS topologies (ie. transformerless, using fast IGBTs and/or a floating battery with respect to earth ground). Applications UPS Telecommunications Battery supplied applications Application Domains Energy & Automation Industrial. Utilities Fire & Safety system Remote monitoring LEM Part Number BM Sentinel 3+ Technology SoC 3 in 1 sensor CE Approved Yes Supply Voltage 0.9 .. 16VDC @ 30mA Voltage Measurement Range 0.9 .. 16VDC @ 30mA Temperature Measurement Range -10°C / 70°C Output S-Bus Digital protocol Isolation 2.16kV (AC, 50Hz, 1 min) S-Bus Baud Rate 9600 bps Mounting Style Din Rail Mount Operating Temperature Range -10°C / 70°C Accuracy 0.5% Termination Style 6 Pin Connector (for BM CBL POW 0.4/0.6M) Unit Weight 70g Factory Pack Qty 6 Datasheet Used to monitor and measure battery Impedance, Voltage, and Surface Temperature. Product Datasheet S-Bus Protocol Information OEM Software Tools Sentinel 3 Commander Test Program Sentinel Troubleshooting Harsh EMC Application Notes In a UPS, the current drawn by the inverter contains line frequency harmonic components (mostly 2nd, 4th and 6th). Part of this ripple current flows through the battery, to which is connected the Sentinel. As the Sentinel itself uses an excitation current for the impedance measurement, so the presence of ripple current can interfere with the measurement and thus cause errors. The table below quantifies the additional error resulting from 1A rms of ripple current, for different combinations of ripple current harmonics and bloc voltage. Table 1: Additional errors for impedance measurement due to ripple current (See datasheet) Notes: The error values are the maximum, and are normalized for 1A rms of ripple current. The error is proportional to the ripple current; for example, if the ripple current was 2A rms the error will increase by factor 2.
