RV & Marine Battery Monitor

Amp hour and Watt hour battery monitors for RV, Boat and Marine use

An RV or marine battery monitor should at least tell you the Amp hours of energy drawn from your battery in addtion to the current. Our "Watt's up" and Doc Wattson DC meters are battery monitors that do these measurements and so much more.

Doc Wattson DC Ammeter for RV & Marine use
Doc Wattson shows Ah, KWh, peak & min
values sequentially in display's lower left corner

* Review our meter's user manual *

BOTH meter models measure the DC values:

  • Amps: (0-100 peak)
  • Watts: (0 - 6554)
  • Peak Amps
  • Minimum Voltage ("sags")
  • Voltage: (0 - 60)

The Doc Wattson increases these two value ranges:

  • Amp-Hours: (0 - 6554)
  • Kilo Watt-hours: (0 - 650)

The "Watt's Up" adds:

  • Peak Watts
  • Amp-Hours: (0 - 65)
  • Kilo Watt-hours: (0 - 6.5)

Choose your meter based on the maximum Amp hours or Watt hours your system will use.

See how to use our meters.

Both "Watt's up" and Doc Wattson DC meters work with 12, 24, 36 and 48 volt batteries up to 60 V. Lead acid, SLA, Gel Cell, NiCad, Li-Poly and other battery types are all compatible since the electrical values measured don't depend on battery chemistry.

The Amp hour (Ah) and Kilo Watt hour (KWh) measurements are much more accurate "fuel gages" than voltage measurements which depend on many other factors. Kilo Watt Hours are better than Amp hours because the effects of voltage change are included in calculating the actual energy delivered to the load. Ah and KWh are much more accurate than the voltage based RV or marine "Battery Indicator" measurements.

Peak Amps and minimum volts measurements show you even short duration load events and help you troubleshoot hard to find electrical problems. Statistics are reset when power is removed.

Our "Watt's up" and Doc Wattson meters are handy battery monitors that help you evaluate the effect of equipment changes and help tuning your system's performance.

Easy To Use

See example connection diagrams.

Feature Summary

  • Low cost
  • Easy to use
  • Made in USA to ISO 9001 (like Hewlett Packard uses) quality standards
  • Self powered (~ 0.007 Amps) or use an auxiliary power source or battery
  • Built-in 0.001 Ohm current shunt
  • High contrast LCD display
  • 14 gage, stranded, high flex, high temperature silicone rubber insulated wires. Supplied without connectors
  • Small size and lightweight - 2.8" L x 1.7" W x 0.83" D, 2.3 oz.
  • Full manual with electrical tutorial
  • One Year Warranty


See more detailed Doc Wattson specifications and features.

Power Options

Doc Wattson draws very little current (~ 0.007 Amps) from your main battery. Or you can choose to power it (using our auxiliary power connector cable) with an auxiliary battery or power source. Auxiliary power has a wide voltage range.



Try our meter simulator and see how the similar "Watt's Up" meter works.

Note that the Simulator doesn't have the Ah and Wh range of the Doc Wattson meter.

RV Battery Monitor