Battery Monitoring

Battery monitors from philippi – precise battery monitoring for boats, yachts & vehicles

philippi battery monitors show state of charge, current, voltage and remaining run time of the on-board battery at any time – on a colour touchscreen right on board. The BLS and BLM2 sets are suitable for lead-acid, GEL, AGM and LiFePO4, and the LTM is designed specifically for lithium. The BLM2 and BTM2 pass their data to compatible chartplotters via NMEA 2000.

In brief: A battery monitor uses a digital precision shunt to measure the actual charge and discharge current and calculates the state of charge from it – far more accurately than a voltage measurement alone. It also records how the battery is used: charge cycles, deep discharges and average depth of discharge. How to install and calibrate shunt and monitor correctly is explained in the Academy section Measuring and monitoring.

Which battery monitor fits?

The philippi battery monitors

BLS set and BLS set Plus – compact with 2.4″ touchscreen

The BLS set monitors a 12/24 V starter battery and one or more parallel 12/24 V service batteries. It shows voltage, charge and discharge current, remaining time and state of charge, plus charge cycles, deep discharges and average depth of discharge; an adjustable alarm warns of deep discharge. The SHE 348 shunt is included. The BLS set Plus additionally contains the ACE-LIN interface, so you can control a philippi ACE series charger from the display, including power reduction and silent mode.

BLM2 set – 3.5″ touchscreen with NMEA 2000

The BLM2 set shows all battery system data on a 3.5″ colour touchscreen and, via NMEA 2000 or SeaTalk NG, on the chartplotter too; the N2K cable is available as an accessory. The SHE 348 shunt is included. Optionally, a third battery bank can be added via voltage monitoring, and solar yield with the SHP 348 shunt. The potential-free changeover contact works with the FHR 265 remote main switch to disconnect loads before deep discharge.

BTM2 – battery and tank monitor for 12 to 48 V

Via the SHE 348 shunt, the BTM2 measures voltage, current, remaining time, temperature and state of charge of the service battery and also monitors up to two starter or bow thruster batteries as well as the tanks. It works with 12 to 48 V and passes all data on via NMEA 2000. It supports the TGT/TGW, UTV, TDS/TDN and DFS senders as well as third-party senders with 10–180 Ω, 240–33 Ω, 0–5 V, 0–10 V or 4–20 mA. Shunt, tank sensors and N2K cable are ordered separately.

LTM – battery and tank monitor for lithium batteries

The LTM is designed for lithium batteries (LiFePO4) and shows battery, tank and charging data on a 3.5″ touchscreen with brightness sensor. Because the flat discharge curve of lithium makes voltage monitoring difficult, it measures capacity via a shunt. SHE 348 shunt, tank sensors and ACE-LIN interface are ordered separately.

philippi Control Unit PCU – monitoring and control in one

The PCU shows battery status, tanks and energy flow on a touch display and controls devices such as fridge, heating and air conditioning via CI and CAN bus, for 12 and 24 V. Victron inverter/chargers and solar controllers can be integrated via the Smart Interface.

Balmar battery monitors and DCA2 leakage current monitor

The Balmar battery monitors of the SG200 family show the state of charge and state of health of the battery bank for 12 to 48 V systems, the SG230/SG235 variants also via NMEA 2000. The DCA2 leakage current monitor uses the SHP-50 shunt to measure leakage current between onboard ground and hull and warns of corrosion.

All philippi monitors compared

Battery management shunts – the heart of the measurement

SHE 348 – battery management shunt: Installed in the negative cable of the service battery, it provides the basic current measurement for the BLS, BLM2 and BTM2. It records currents from 10 mA to 300 A continuous with ±0.5 % accuracy, for battery capacities up to 50,000 Ah, and also measures the starter battery voltage.

SHP 348 – additional shunt: Adds a second, independent current measurement to the PCU, BTM2, BLM2 and LTM, for example for the solar system, also from 10 mA to 300 A with ±0.5 %.

NMEA 2000 – battery data on the chartplotter

The BLM2 set and BTM2 make their data available to the onboard network via NMEA 2000 so that it appears on compatible chartplotters; the N2K cable is required. For Raymarine networks via SeaTalk, the Seatalk/NMEA 2000 adapter cable (A06045) is available.

Frequently asked questions about philippi battery monitors

What is the difference between the BLS and the BTM2?

The BLS set is the compact monitor with a 2.4-inch display for pure battery monitoring of starter and service batteries in 12 and 24 V systems, shunt included. The BTM2 has a 3.5-inch display, also monitors the tanks, passes its data to the chartplotter via NMEA 2000 and works from 12 to 48 V.

Which monitor do I need for lithium batteries (LiFePO4)?

The BLS set and BLM2 set are suitable for lead-acid, GEL, AGM and LiFePO4 and measure current via the SHE 348 shunt. The LTM is designed specifically for lithium batteries and combines battery, tank and charge monitoring. Important with lithium: via the changeover contact of the BLM2 or BTM2, the FHR 265 main switch disconnects loads before deep discharge.

Which shunt suits which monitor?

The SHE 348 shunt provides the basic current measurement for the BLS, BLM2 and BTM2 and sits in the negative cable of the service battery. It measures 10 mA to 300 A continuous with ±0.5 % accuracy, for capacities up to 50,000 Ah. For a second measurement, such as solar, the SHP 348 extends the PCU, BTM2, BLM2 and LTM.

Can I display solar data on the monitor?

Yes. With the optional SHP 348 additional shunt, the BTM2, BLM2 and LTM measure a further energy source separately, for example the solar system, and show output and energy yield. This lets you see how much your panels actually deliver and compare consumption on board with the yield.

Can the monitors communicate with the ACE charger?

Yes. Via the optional ACE-LIN interface, philippi ACE chargers can be integrated into the monitor. Charging voltage, charging current, charging phase and battery temperature then appear directly on the display, and the charging power can also be set there. This gives you charging and consumption on a single screen.