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Sentinel 300P Series Battery Chargers

Sentinel 300P battery chargers provide new levels of DC power control, monitoring and protection for stationary engine starting and standby battery applications. Its flexible configuration, with microprocessor programmability, allows for automatic or manual configuration of charge output voltages (12 or 24V nominal), cell types/numbers and application – all in one standard model. Programming is by circuit board links or PC-based software configuration and monitoring tool. The Sentinel 300P is available either as an open-frame, UL-recognized module for mounting in existing control panels, or as a UL-listed, wall-mounted stainless steel enclosure with LCD and analogue metering options.

murphy sentinel 300P battery charger



Power supply
Operating voltage:  95 – 250 VAC
Operating frequency:  47 – 63 Hz.

DC Charge Output
Nominal voltage:  programmable 12 or 24 VDC
Float/boost voltage:  programmable (see panel 5: "Output Calibration")
Maximum current limit:  10 A
Voltage ripple:  < 1%
Line regulation:  < 2%
Load regulation:  < 2%

Outputs x3 ( x4 for non-CAN configurations ):
All models:
1 x SPCO (RL1), 1 x SPNC (RL2), 1 x SPNO (RL3), dry/volt-free contacts (common feed for RL1, RL2 & RL3)
Standard models (non-CAN configurations):
1 x SPNC (RL4), dry/volt-free contacts standard output functions (charge fail, AC fail, low battery volts, high battery volts) are NFPA 110 compliant.
Rating (all relays):  1A max @ 30 VDC (resistive load), UL class 2

Inputs x2:
Closed to negative DC to activate, configurable function

Operating temperature:  -40° to +140°F / -40° to +60°C
Display viewability (LCD models):  32° to 122°F / 0° to 50°C
Humidity:  20% to 90% RH
Dimensions:  see panels 3 & 4 "Dimensions"
Weight:  see panels 3 & 4 "Dimensions"
Electrical safety:  2006/95/EC
Electromagnetic compatibility:  2004/108/EC, EN 55022 class B (EN 61000-6-1, EN 61000-6-3)

UL approvals
All standard (E)SNTL300P models:  BBGQ: UL1236, CSA22.2 no. 107.2; BBHH: UL1236 SE

murphy sentinel 300P electrical diagram

1) AC input fusing (F1): replaceable, circuit board mounted fuse, rating as shown on the product label.
2) DC output fusing: all models include a self-resetting electronic output fuse.
3) DC output is isolated from chassis.
4) connection shown for standard configurations with output RL4. (RL4 is not available on units configured for CAN communication)

Open-frame SNTL300P

murphy sentinel 300P dimensional diagram

Optional clip for DIN rail mounting (2 required for each charger), Part # 045-0001

W     6.22 in. / 158 mm
H      8.19 in. / 208 mm
D      3.31 in. / 84 mm

Fixing holes:
X      5.91 in. / 150 mm
Y      5.91 in. / 150 mm

2.5 lb. / 1.1 kg

Dimensions for reference only. Use actual product for mounting template. For safe heat dissipation, mount product in orientation shown, with minimum air-gap clearance of 1.5 in./40mm above/below and 1.0 in./25mm at each side.

Enclosed ESNTL300P

murphy sentinel 300P dimensional diagram

W       6.50 in. / 165mm
H1      11.81 in. / 300 mm
H2      3.15 in. / 80 mm
D1      4.72 in. / 120 mm
D2      5.12 in. / 130 mm

Fixing holes:
X      2.50 in. / 63.5 mm
Y      11.25 in. / 285.5 mm

22.0 lb / 10.0 kg

Dimensions for reference only. Use actual product for mounting template. For safe heat dissipation, mount product in orientation shown, with minimum air-gap clearance of 1.5 in./40mm above/below and 1.0 in./25mm at each side.

murphy sentinel 300P output calibration diagram

Battery type is selected by circuit board DIP switches or SNTL-PCSUITE configuration software. Calibration figures at 20°C. If temperature compensation is enabled, and remote SNTL-RTC temperature sensor connected, output voltage automatically varies by 3mV per cell per 1°C deviation from 20°C, within the range –10° to +50°C. Increasing temperatures give decreasing outputs; decreasing temperatures give increasing outputs.

murphy sentinel 300P how to order diagram


Standard Sentinel 300P Charging Features:

•  Microprocessor controlled, programmable battery charger
•  High rate, low ripple float charging: 10A@ 12/24 VDC
•  <1% ripple, beneficial for vented lead acid & NiCd cells, essential for VRLA
•  Configurable for use as a stand-alone DC power supply
•  AutoBoost is triggered automatically on low charge levels, or manually by remote switch
•  AutoBoost temporarily increases the charge voltage before returning to float mode, and maximizes cell capacity and life
•  Temperature compensation ensures batteries are charged at the optimal voltage, which varies significantly with ambient temperature
•  Options for RS485/CAN connectivity, SAE J1939 data communication, backlit display and analog meters
•  UL, CSA , CE and NFPA 110 compliant
•  Panel mount module or wall mounted, stainless steel enclosure
•  For stationary engine, genset and standby power applications


Browse through the menu below to download information for the Sentinel 300P in PDF format:



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