Sentinel 150 Series

  • Switch mode power supply technology: light and compact, power efficient with low heat dissipation
  • High rate, low ripple float charging: 5 or 10A @ 12 VDC, 5A @ 24 VDC
  • AutoBoost and temperature compensation
  • Open-frame (protective cover) or stainless steel, wall mounted case options
  • For stationary engine, genset and standby power applications
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Product Overview: 

The Sentinel 150 line provides high performance battery charging for continuous float charge and standby power applications. Switch mode technology provides major advances in power supply and battery charger design, giving a compact and lightweight construction, improved power efficiency, low heat dissipation, wide supply voltage tolerance and low output ripple.  

The chargers are configured for fast, accurate charging to give optimum battery life and reliability. The very smooth output (<1% ripple) allows charging of sealed or vented batteries – e.g., Nickel Cadmium (NiCd), Lead Acid Sealed (VRLA), vented and Planté cells – or use as a stand-alone power supply. Factory calibration is optimized for each specific battery type.


All models feature an intelligent, multistage charge regime.  During charge recovery mode, the Sentinel gives a constant (maximum) current output. As the battery approaches peak charge, the output reverts to float charge mode, maintaining an optimum cell voltage  and supplying additional standing load current up to the rated maximum. Output current is always limited to the rated maximum, even during high load (e.g., engine cranking), short circuit or reverse polarity connection. 

AutoBoost provides a temporary increase in output voltage, equalizing the charge between cells and maximizing battery life and capacity. AutoBoost is triggered automatically when the battery falls below a preset voltage or can be initiated manually through a momentary switch input. At the end of the Auto-Boost cycle, Sentinel automatically reverts to normal float charge mode, preventing battery overcharge and gassing.  

Alarm Outputs
Sentinel UL150 models include a self-diagnostic circuit for monitoring charge fail fault conditions (AC supply/fuse failure, DC fuse failure or low/no charge current), with a solid-state relay output for driving a remote alarm or fault annunciator. Enclosed NFPA models have NFPA 110 compliant alarms for AC failure, charge fail, high battery volts and low battery volts.  

Temperature Compensation
The optimum charge voltage for lead acid and NiCd batteries varies with ambient temperature. Sentinel can be configured to sense battery temperature from a remote sensor and automatically compensate the output charge voltage.  

Installation and Connection
UL-recognized SNTLUL150 model uses an open frame circuit board and base/heatsink with protected cover for surface or DIN rail mounting in an existing control panel. UL-listed ESNTLUL150 models use a stainless steel, wall-mounted case.

Electrical connection is by screw terminal blocks. Connection and cable access on ESNTL models is by a hinged front plate and knock-out sections in the enclosure side.