Leisure Electrics
What is a Battery Monitor?
The little screen (or app) that tells you how much power you actually have left.
Simplified animation — not to scale.
In plain English
A battery monitor measures the current flowing in and out of your leisure battery and works out a genuine percentage — far more accurate than judging it by how bright your lights look.
How it works
A shunt is fitted in-line with the negative battery terminal. It measures amps in real time and a small computer adds it all up over time to estimate the battery's actual state of charge, shown on a panel or phone app.
Signs of trouble
- ⚠Reading stuck or clearly wrong
- ⚠Percentage that doesn't move even while charging
- ⚠No reading at all — usually a blown fuse or loose shunt connection
Rough UK cost
£40 – £250 fitted, depending on whether it's a basic voltage gauge or a full shunt-based monitor with an app.
Ballpark only — depends on your van, converter and local labour rates.
Heads up: CamperAutonomy is for general guidance only. Anything gas-related must be signed off by a Gas Safe engineer with LPG endorsement.
More in Leisure Electrics
Leisure Battery
The separate battery that runs your lights, water pump and fridge — without you ever waking up to a dead engine.
Split Charge Relay / B2B Charger
The clever switch that sends spare engine power to your leisure battery as you drive.
12V Fuse Board / Consumer Unit
The little box of fuses and switches that protects every 12V circuit in the van.