#PRODUCT/REVIEW: A Monitoring System for Multiple RV Battery Banks

BY Marco Kathuria—The Philippi Battery Monitor BLS is a compact battery monitor for battery systems consisting of a 12/24 V starter battery and one or more 12/24 V house batteries connected in parallel. The 2.4″ TFT touch screen displays the current charging state of the entire battery system at a glance in our 1973 GMC Motorhome.

I wanted to find a way to both trickle charge and monitor the voltage of the starter and house battery banks while the RV was parked over the winter. I eventually settled on a combination of the Philippi Battery Monitor BLS system hooked up to a Xantrex Echo Charge for 12 & 24V Systems. The Echo Charge pulls a modest voltage from the converter 12v feed and sends some of it to the engine battery banks.

My Intelli-Power 9200 Series Converter/Charger from Progressive Dynamics was already hooked into the motorhome’s 120v/12v circuits, so it was a simple case of installing the Echo Charge and connecting it to a 12v circuit, the other end connecting to the positive terminal on the engine battery bank. I removed the cable connected to the negative terminal of the house battery bank and installed the provided Shunt between the negative terminal and the cable that I just removed from the negative terminal. I used a bussbar for easy access and setup.

I’d looked at the Victron Energy BMV-700 and Simarine products but found the Victron’s single line readout to not be as informative as I would have liked, and the Simarine Pico Modular System way more than I actually needed, in terms of information presented onscreen, upgradability, modularity, etc. Eventually, I settled on a little-known German company, Philippi, for my solution.

 Philippi Battery Monitor BLS Wiring Diagram

The Phillipi BLS measures the current in and out of the battery being monitored on the negative cable. So the Shunt must be the only item connected to the negative post of whatever battery bank you happen to be monitoring. There can be only one negative cable connected to that battery, and that goes to the Shunt. All other negative wires/cables associated with that battery must be connected to the opposite terminal of the Shunt to the one connected to the battery.

The positive wire for the Philippi BLS went directly to the battery positive post so that it was still operational when the battery switch was turned off. The BLS needed to stay powered to be able to retain the battery information: i.e state of charge, remaining capacity, etc.

The voltage sense wire for the starter battery was then connected to the positive terminal on that battery.

With both battery banks connected to the same panel, the Philippi Battery Monitor BLS allows me to monitor the charged state of both my house and engine battery with a simple tap of the touchscreen. My JRV Products systems monitor panel takes care of monitoring propane, fresh water, black water, and grey water.

Here’s a photo of the final installation as of August, 2022. I’ve since added an iPad mini control panel to manage the solar MPPT controller, Garmin GPS unit, interior LED light strips, and as a music streamer to the Bluetooth-enabled car stereo in the dashboard.

A view of the interior of our 1973 GMC Motorhome showing the Philippi Battery Monitor BLS.

Scroll to the end of this article for information about where to get your Philippi Battery Monitor BLS-Set. Tell them Marco from My Motorhome Life sent you!

Key Features:

  • Display of the current voltage, the current charge or discharge current, the remaining time, the battery temperature and the state of charge of the consumer battery(s)
  • Further information on the use of the consumer battery(s): No. of charge cycles, deep discharges & mean depth of discharge.
  • Warning of a dangerous deep discharge by an adjustable acoustic alarm
  • Suitable for all battery types like acid, GEL, AGM and LiFePO4
  • The built-in brightness sensor automatically dims the screen at night, saving valuable energy.

Technical Specifications:

  • Supply voltage
    DC 8-32 V
  • Current consumption (monitor)
    80 mA at max. Display brightness, 6 mA in sleep mode
  • Current consumption (shunt)
    20 mA, 2 mA in sleep mode
  • Shunt
    0.1 m Ω
  • Measuring range U1
    0-35V, resolution 30mV, accuracy 0.25%
  • Measuring range U2
    0-35V, resolution 30mV, accuracy 0.25%
  • Current carrying capacity
    Shunt 300A, 600A 1 min, 1500A 0.5 s
  • Current carrying capacity relay
    1A
  • Measuring range I, shunt
    -600 – + 600A, resolution 10mV, accuracy 0.5%
  • Measuring range T (external sensor)
    -15 – 60 ° C, resolution 1K, accuracy 1K
  • Dimensions:
  • Monitor L 105 x W 75 x D 40 mm
  • Shunt L 118 x W 40 x H 65 mm

Connections shunt

Bolt M8

Manuals and Other Documents

Battery Monitor BLS Philippi Operating Manual

Battery Monitors Overview BLS Philippi



Product & Sales Enquiries:

OceanPlanet Energy
Shipping Address:
23 Mountain Rd.
Woolwich, ME 04579
ph: 207-370-9112

General Inquiries & product info: [email protected]
Technical support: [email protected]
To place an order for specific products: [email protected]

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